<SUBMISSION>
<ACCESSION-NUMBER>0001047469-04-033436
<TYPE>8-K
<PUBLIC-DOCUMENT-COUNT>4
<PERIOD>20041105
<ITEMS>8.01
<ITEMS>9.01
<FILING-DATE>20041108
<DATE-OF-FILING-DATE-CHANGE>20041108
<FILER>
<COMPANY-DATA>
<CONFORMED-NAME>AVANT IMMUNOTHERAPEUTICS INC
<CIK>0000744218
<ASSIGNED-SIC>2835
<IRS-NUMBER>133191702
<STATE-OF-INCORPORATION>DE
<FISCAL-YEAR-END>1231
</COMPANY-DATA>
<FILING-VALUES>
<FORM-TYPE>8-K
<ACT>34
<FILE-NUMBER>000-15006
<FILM-NUMBER>041126314
</FILING-VALUES>
<BUSINESS-ADDRESS>
<STREET1>119 FOURTH AVE
<CITY>NEEDHAM
<STATE>MA
<ZIP>02494
<PHONE>7814330771
</BUSINESS-ADDRESS>
<MAIL-ADDRESS>
<STREET1>119 FOURTH AVE
<CITY>NEEDHAM
<STATE>MA
<ZIP>021942725
</MAIL-ADDRESS>
<FORMER-COMPANY>
<FORMER-CONFORMED-NAME>T CELL SCIENCES INC
<DATE-CHANGED>19920703
</FORMER-COMPANY>
</FILER>
<DOCUMENT>
<TYPE>8-K
<SEQUENCE>1
<FILENAME>a2146122z8-k.htm
<DESCRIPTION>8-K
<TEXT>
<HTML>
<HEAD>
</HEAD>
<BODY BGCOLOR="#FFFFFF" LINK=BLUE  VLINK=PURPLE>
<BR>
<FONT SIZE=3 ><A HREF="#04BOS2260_1">QuickLinks</A></FONT>
<font size=3> -- Click here to rapidly navigate through this document</font>

<P><FONT SIZE=2>
<hr noshade width=100% align=left size=4>
<hr noshade width=100% align=left size=1> </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=5><B>SECURITIES AND EXCHANGE COMMISSION<BR>  </B></FONT><FONT SIZE=2><B>Washington, D.C. 20549  </B></FONT></P>

<BR>
<P ALIGN="CENTER"><FONT SIZE=5><B>FORM 8-K  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=3><B>Current Report Pursuant<BR>
to Section&nbsp;13 or 15(d) of the<BR>
Securities Exchange Act of 1934  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>Date of Report (Date of earliest event reported)<BR></FONT> <FONT SIZE=2><B>November&nbsp;8, 2004 (November&nbsp;5, 2004)  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=5><B>AVANT Immunotherapeutics,&nbsp;Inc.<BR>  </B></FONT><FONT SIZE=2>(Exact name of registrant as specified in charter) </FONT></P>

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<TD WIDTH="32%" ALIGN="CENTER"><FONT SIZE=2><B>Delaware<BR> </B></FONT><FONT SIZE=2>(State or other jurisdiction<BR>
of incorporation)</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="32%" ALIGN="CENTER"><FONT SIZE=2><B>1-15629<BR> </B></FONT><FONT SIZE=2>(Commission file number)</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="32%" ALIGN="CENTER"><FONT SIZE=2><B>13-3191702<BR> </B></FONT><FONT SIZE=2>(IRS employer<BR>
identification no.)</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD COLSPAN=5 ALIGN="CENTER" VALIGN="TOP"><FONT SIZE=2><BR>
<BR></FONT> <FONT SIZE=2><B>119 Fourth Avenue<BR>
Needham, MA 02494-2725<BR> </B></FONT><FONT SIZE=2>(Address of principal executive offices) (Zip code)</FONT></TD>
</TR>
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<P ALIGN="CENTER"><FONT SIZE=2>Registrant's
telephone number, including area code: </FONT><FONT SIZE=2><B>(781)&nbsp;433-0771</B></FONT></P>

<P><FONT SIZE=2>Check
the appropriate box below if the Form 8-K filing is intended to simultaneously satisfy the filing obligation of the registrant under any of the following provisions: </FONT></P>

<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2><FONT FACE="WINGDINGS">&#111;</FONT></FONT></DT><DD><FONT SIZE=2>Written
communications pursuant to Rule&nbsp;425 under the Securities Act (17&nbsp;CFR&nbsp;230.425)
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2><FONT FACE="WINGDINGS">&#111;</FONT></FONT></DT><DD><FONT SIZE=2>Soliciting
material pursuant to Rule&nbsp;14a-12 under the Exchange Act (17&nbsp;CFR&nbsp;240.14a-12)
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2><FONT FACE="WINGDINGS">&#111;</FONT></FONT></DT><DD><FONT SIZE=2>Pre-commencement
communications pursuant to Rule&nbsp;14d-2(b) under the Exchange Act
(17&nbsp;CFR&nbsp;240.14d-2(b))
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2><FONT FACE="WINGDINGS">&#111;</FONT></FONT></DT><DD><FONT SIZE=2>Pre-commencement
communications pursuant to Rule&nbsp;13e-4(c) under the Exchange Act
(17&nbsp;CFR&nbsp;240.13e-4(c)) </FONT></DD></DL>
<BR>

<P><FONT SIZE=2><hr
noshade width=100% align=left size=1>
<hr noshade width=100% align=left size=4> </FONT></P>

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<P><FONT SIZE=2><A
NAME="de2260_item_8.01._other_events"> </A>
<A NAME="toc_de2260_1"> </A>
<BR></FONT><FONT SIZE=2><B>Item 8.01. Other Events    <BR>    </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;On November&nbsp;5, 2004 the Board of Directors of AVANT Immunotherapeutics,&nbsp;Inc. (the "Company") adopted a new Shareholder Rights Plan, as set forth in
the Shareholder Rights Agreement, dated November&nbsp;5, 2004, between the Company and EquiServe Trust Company, N.A., as Rights Agent (the "Rights Agreement"). The Rights Agreement replaces the
Company's existing Shareholder Rights Agreement which expires on November&nbsp;10, 2004. The following description of the terms of the Rights Agreement does not purport to be complete and is
qualified in its entirety by reference to the Rights Agreement which is attached hereto as an exhibit and is incorporated herein by reference. </FONT></P>


<P><FONT SIZE=2><B>Rights Dividend  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant to the terms of the Rights Agreement, the Board of Directors declared a dividend distribution of one Preferred Stock Purchase Right (a "Right") for each
outstanding share of Common Stock of the Company (the "Common Stock") to shareholders of record as of the close of business on November&nbsp;11, 2004 (the "Record Date"). In addition, one Right will
automatically attach to each share of Common Stock issued between the Record Date and the Distribution Date (as hereinafter defined). Each Right entitles the registered holder thereof to purchase from
the Company a unit consisting of one ten-thousandth of a share (a "Unit") of Series&nbsp;C-1 Junior Participating Cumulative Preferred Stock, par value $0.01 per share, of
the Company (the "Preferred Stock") at a cash exercise price of $35.00 per Unit (the "Exercise Price"), subject to adjustment, under certain conditions specified in the Rights Agreement and summarized
below. </FONT></P>

<P><FONT SIZE=2><B>Distribution Date  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Initially, the Rights are not exercisable and are attached to and trade with all shares of Common Stock outstanding as of, and issued subsequent to, the Record
Date. The Rights will separate from the Common Stock and will become exercisable upon the earlier of (i)&nbsp;the close of business on the tenth calendar day following the first public announcement
that a person or group of affiliated or associated persons (an "Acquiring Person") has acquired beneficial ownership of 15% or more of the outstanding shares of Common Stock, other than as a result of
repurchases of stock by the Company or certain inadvertent actions by a shareholder (the date of said announcement being referred to as the "Stock
Acquisition Date"), or (ii)&nbsp;the close of business on the tenth business day (or such later day as the Board of Directors may determine) following the commencement of a tender offer or exchange
offer that could result upon its consummation in a person or group becoming the beneficial owner of 15% or more of the outstanding shares of Common Stock (the earlier of such dates being herein
referred to as the "Distribution Date"). </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Notwithstanding
the foregoing, with respect to any person who beneficially owns (for purposes of the Rights Agreement) 15% or more of the outstanding shares of Common Stock as of
November&nbsp;6, 2004 (such person being referred to in the Rights Agreement as a "Grandfathered Person"), the Distribution Date will not occur unless such Grandfathered Person has acquired
beneficial ownership of shares of Common Stock representing an additional <SUP>1</SUP>/<SMALL>2</SMALL>% of the outstanding shares of Common Stock. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In
the event that a Stock Acquisition Date occurs, proper provision will be made so that each holder of a Right (other than an Acquiring Person or its associates or affiliates, whose
Rights shall become null and void) will thereafter have the right to receive upon exercise, in lieu of a number of Units of Preferred Stock, that number of shares of Common Stock of the Company (or,
in certain circumstances, including if there are insufficient shares of Common Stock to permit the exercise in full of the Rights, Units of Preferred Stock, other securities, cash or property, or any
combination of the foregoing) having a market value of two times the exercise price of the Right (such right being referred to as the "Subscription Right"). In the event that, at any time following
the Stock Acquisition Date, </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>2</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<A NAME="page_de2260_1_3"> </A>
<BR>

<P><FONT SIZE=2>(i)&nbsp;the
Company consolidates with, or merges with and into, any other person, and the Company is not the continuing or surviving corporation, (ii)&nbsp;any person consolidates with the
Company, or merges with and into the Company and the Company is the continuing or surviving corporation of such merger and, in connection with such merger, all or part of the shares of Common Stock
are changed into or exchanged for stock or other securities of any other person or cash or any other property, or (iii)&nbsp;50% or more of the Company's assets or earning power is sold, mortgaged
or otherwise transferred, each holder of a Right (other than an Acquiring Person or its associates or affiliates, whose Rights shall become null and void) will thereafter have the right to receive,
upon exercise, common stock of the acquiring company having a market value equal to two times the exercise price of the Right (such right being referred to as the "Merger Right"). The holder of a
Right will continue to have the Merger Right whether or not such holder has exercised the Subscription Right. Rights that are or were beneficially owned by an Acquiring Person may (under certain
circumstances specified in the Rights Agreement) become null and void. </FONT></P>


<P><FONT SIZE=2><B>Redemption  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The Rights may be redeemed in whole, but not in part, at a price of $0.01 per Right (payable in cash, Common Stock or other consideration deemed appropriate by
the Board of Directors) by the Board of Directors only until the earlier of (i)&nbsp;the time at which any person becomes an Acquiring Person, or (ii)&nbsp;the expiration date of the Rights
Agreement. Immediately upon the action of the Board of Directors
ordering redemption of the Rights, the Rights will terminate and thereafter the only right of the holders of Rights will be to receive the redemption price. </FONT></P>


<P><FONT SIZE=2><B>Amendment  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The Rights Agreement may be amended by the Board of Directors in its sole discretion until the time at which any person becomes an Acquiring Person. After such
time the Board of Directors may, subject to certain limitations set forth in the Rights Agreement, amend the Rights Agreement only to cure any ambiguity, defect or inconsistency, to shorten or
lengthen any time period, or to make changes that do not adversely affect the interests of Rights holders (excluding the interests of an Acquiring Person or its associates or affiliates). In addition,
the Board of Directors may at any time prior to the time at which any person becomes an Acquiring Person, amend the Rights Agreement to lower the threshold at which a person becomes an Acquiring
Person to not less than the greater of (i)&nbsp;the sum of .001% and the largest percentage of the outstanding Common Stock then owned by any person, and (ii)&nbsp;10%. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Until
a Right is exercised, the holder will have no rights as a stockholder of the Company (beyond those as an existing stockholder), including the right to vote or to receive dividends.
While the distribution of the Rights will not be taxable to stockholders or to the Company, stockholders may, depending upon the circumstances, recognize taxable income in the event that the Rights
become exercisable for Units, other securities of the Company, other consideration or for common stock of an acquiring company. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The
Rights are not exercisable until the Distribution Date and will expire at the close of business on November&nbsp;11, 2014 (the "Expiration Date"), unless previously redeemed or
exchanged by the Company as described below. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>3</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<A NAME="page_de2260_1_4"> </A>
<BR>

<P><FONT SIZE=2><A
NAME="de2260_item_9.01._financial_statement__ite02764"> </A>
<A NAME="toc_de2260_2"> </A>
<BR></FONT><FONT SIZE=2><B>Item 9.01. Financial Statements, Pro Forma Financial Information and Exhibits    <BR>    </B></FONT></P>

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<TH WIDTH="3%" ALIGN="CENTER"><FONT SIZE=1>&nbsp;</FONT><BR></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="17%" ALIGN="LEFT"><FONT SIZE=1>&nbsp;</FONT><BR></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="76%" ALIGN="LEFT"><FONT SIZE=1>&nbsp;</FONT><BR></TH>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="17%" ALIGN="RIGHT"><FONT SIZE=2>Exhibit&nbsp;3.1&#151;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="76%"><FONT SIZE=2>Certificate of Designations, Preferences and Rights of a Series of Preferred Stock of AVANT Immunotherapeutics,&nbsp;Inc. classifying and designating the Series&nbsp;C-1 Junior Participating Cumulative Preferred Stock,
filed as an exhibit to the Company's Registration Statement on Form&nbsp;8-A on November&nbsp;8, 2004.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="3%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="17%" ALIGN="RIGHT"><FONT SIZE=2><BR>
Exhibit&nbsp;4.1&#151;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="76%"><FONT SIZE=2><BR>
Shareholder Rights Agreement, dated as of November&nbsp;5, 2004 between AVANT Immunotherapeutics,&nbsp;Inc. and EquiServe Trust Company, N.A., as Rights Agent, filed as an exhibit to the Company's Registration Statement on Form&nbsp;8-A on
November&nbsp;8, 2004.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="3%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="17%" ALIGN="RIGHT"><FONT SIZE=2><BR>
Exhibit&nbsp;99.1&#151;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="76%"><FONT SIZE=2><BR>
Press Release issued by AVANT Immunotherapeutics,&nbsp;Inc. dated November&nbsp;5, 2004.</FONT></TD>
</TR>
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<P ALIGN="CENTER"><FONT SIZE=2>4</FONT></P>

<HR NOSHADE>
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<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="jc2260_signature"> </A>
<A NAME="toc_jc2260_1"> </A>
<BR></FONT><FONT SIZE=2><B>SIGNATURE    <BR>    </B></FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant to the requirements of the Securities Exchange Act of 1934, the Registrant has duly caused this report to be signed on its behalf by the undersigned
hereunto duly authorized. </FONT></P>

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<TD WIDTH="39%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD COLSPAN=2><FONT SIZE=2>AVANT IMMUNOTHERAPEUTICS,&nbsp;INC.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2><BR>
Date: November&nbsp;8, 2004</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="4%"><FONT SIZE=2><BR>
By:</FONT></TD>
<TD WIDTH="54%"><FONT SIZE=2><BR>
/s/&nbsp;&nbsp;</FONT><FONT SIZE=2>UNA S. RYAN</FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT><HR NOSHADE><FONT SIZE=2> Name: Una S. Ryan, Ph.D<BR>
Title: President and Chief Executive Officer</FONT></TD>
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<P ALIGN="CENTER"><FONT SIZE=2>5</FONT></P>

<HR NOSHADE>
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<P><FONT SIZE=2><A
NAME="page_je2260_1_6"> </A> </FONT> <FONT SIZE=2><B>EXHIBIT INDEX  </B></FONT></P>

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<TH WIDTH="9%" ALIGN="LEFT"><FONT SIZE=1><B>Exhibit No.<BR> </B></FONT><HR NOSHADE></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="89%" ALIGN="CENTER"><FONT SIZE=1><B>Description</B></FONT><HR NOSHADE></TH>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="9%" ALIGN="RIGHT"><FONT SIZE=2>3.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2>Certificate of Designations, Preferences and Rights of a Series of Preferred Stock of AVANT Immunotherapeutics,&nbsp;Inc. classifying and designating the Series&nbsp;C-1 Junior Participating Cumulative Preferred Stock,
filed as an exhibit to the Company's Registration Statement on Form&nbsp;8-A on November&nbsp;8, 2004.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="9%" ALIGN="RIGHT"><FONT SIZE=2><BR>
4.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Shareholder Rights Agreement, dated as of November&nbsp;5, 2004 between AVANT Immunotherapeutics,&nbsp;Inc. and EquiServe Trust Company, N.A., as Rights Agent, filed as an exhibit to the Company's Registration Statement on Form&nbsp;8-A on
November&nbsp;8, 2004.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="9%" ALIGN="RIGHT"><FONT SIZE=2><BR>
99.1</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="89%"><FONT SIZE=2><BR>
Press Release issued by AVANT Immunotherapeutics,&nbsp;Inc. dated November&nbsp;5, 2004.</FONT></TD>
</TR>
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<P ALIGN="CENTER"><FONT SIZE=2>6</FONT></P>

<HR NOSHADE>
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<BR>
<P><br><A NAME="04BOS2260_1">QuickLinks</A><br></P><!-- TOC_BEGIN -->
<UL>
<FONT SIZE=2><A HREF="#toc_de2260_1">Item 8.01. Other Events</A></FONT><BR>
<FONT SIZE=2><A HREF="#toc_de2260_2">Item 9.01. Financial Statements, Pro Forma Financial Information and Exhibits</A></FONT><BR>
</UL>
<!-- TOC_BEGIN -->
<FONT SIZE=2><A HREF="#toc_jc2260_1">SIGNATURE</A></FONT><BR>
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</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-3.1
<SEQUENCE>2
<FILENAME>a2146122zex-3_1.htm
<DESCRIPTION>EXHIBIT 3.1
<TEXT>
<HTML>
<HEAD>
</HEAD>
<BODY BGCOLOR="#FFFFFF" LINK=BLUE  VLINK=PURPLE>
<BR>
<FONT SIZE=3 ><A HREF="#04BOS2260_2">QuickLinks</A></FONT>
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<P ALIGN="RIGHT"><FONT SIZE=2><A
NAME="ke2260_exhibit_3.1"> </A>
<A NAME="toc_ke2260_1"> </A>
<BR></FONT><FONT SIZE=2><B>Exhibit 3.1    <BR>    </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>CERTIFICATE OF DESIGNATIONS, PREFERENCES<BR>
AND RIGHTS OF A SERIES OF<BR>
PREFERRED STOCK  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</FONT> <FONT SIZE=2><B>OF</B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>AVANT IMMUNOTHERAPEUTICS,&nbsp;INC.  </B></FONT></P>

<HR NOSHADE ALIGN="CENTER" WIDTH="120">

<P><FONT SIZE=2>AVANT
IMMUNOTHERAPEUTICS,&nbsp;INC., a corporation organized and existing under the General Corporation Law of the State of Delaware, </FONT></P>


<P><FONT SIZE=2>DOES
HEREBY CERTIFY: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;That,
pursuant to authority conferred upon the Board of Directors by the Third Restated Certificate of Incorporation, as amended, of said corporation, and pursuant to the provisions of
Section&nbsp;151 of Title 8 of the Delaware Code of 1953, said Board of Directors, at a meeting duly held on November&nbsp;5, 2004, adopted a resolution providing for the designations, preferences
and relative, participating, optional or
other rights, and the qualifications, limitations or restrictions thereof, of a Series of Preferred Stock, which resolution is as follows: </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>See
attached pages 2A-7A </FONT></P>

<HR NOSHADE>
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<A NAME="page_ke2260_1_2"> </A>
<P ALIGN="CENTER"><FONT SIZE=2><B>VOTE OF DIRECTORS ESTABLISHING<BR>
SERIES C-1 JUNIOR PARTICIPATING CUMULATIVE<BR>
PREFERRED STOCK<BR>
of<BR>
AVANT IMMUNOTHERAPEUTICS,&nbsp;INC.  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant to Section&nbsp;151 of the General Corporation Law of the State of Delaware: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;VOTED,
that pursuant to authority conferred upon and vested in the Board of Directors by the Third Restated Certificate of Incorporation, as amended (the "Certificate of Incorporation"),
of AVANT Immunotherapeutics,&nbsp;Inc. (the "Corporation"), the Board of Directors hereby establishes and designates a series of Preferred Stock of the Corporation, and hereby fixes and determines
the relative rights and preferences of the shares of such series, in addition to those set forth in the Certificate of Incorporation, as follows: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;1.
</FONT><FONT SIZE=2><I>Designation and Amount.</I></FONT><FONT SIZE=2> The shares of such series shall be designated as "Series&nbsp;C-1 Junior
Participating Cumulative Preferred Stock" (the "Series&nbsp;C-1 Preferred Stock"), and the number of shares initially constituting such series shall be 150,000; provided, however, that
if more than a total of 150,000 shares of Series&nbsp;C-1 Preferred Stock shall be issuable upon the exercise of Rights (the "Rights") issued pursuant to the Shareholder Rights Agreement
dated as of November&nbsp;5 2004, between the Corporation and EquiServe Trust Company, N.A., as Rights Agent (the "Rights Agreement"), the Board of Directors of the Corporation, pursuant to
Section&nbsp;151(g) of the General Corporation Law of the State of Delaware, may direct by resolution or resolutions that a certificate be properly executed, acknowledged, filed and recorded, in
accordance with the provisions of Section&nbsp;103 thereof, providing for the total number of shares of Series&nbsp;C-1 Preferred Stock authorized to be issued to
be increased (to the extent that the Certificate of Incorporation then permits) to the largest number of whole shares (rounded up to the nearest whole number) issuable upon exercise of such Rights. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;2.
</FONT><FONT SIZE=2><I>Dividends and Distributions.</I></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(A)
(i) Subject to the rights of the holders of any shares of any series of preferred stock (or any similar stock) ranking prior and superior to the Series&nbsp;C-1
Preferred Stock with respect to dividends, the holders of shares of Series&nbsp;C-1 Preferred Stock, in preference to the holders of shares of common stock and of any other junior stock,
shall be entitled to receive, when, as and if declared by the Board of Directors out of funds legally available for the purpose, quarterly dividends payable in cash on the first day of March, June,
September and December in each year (each such date being referred to herein as a "Quarterly Dividend Payment Date"), commencing on the first Quarterly Dividend Payment Date after the first issuance
of a share or fraction of a share of Series&nbsp;C-1 Preferred Stock, in an amount per share (rounded to the nearest cent) equal to the greater of (a)&nbsp;$1.00 or (b)&nbsp;subject
to the provisions for adjustment hereinafter set forth, 10,000 times the aggregate per share amount of all cash dividends, and 10,000 times the aggregate per share amount (payable in kind) of all
non-cash dividends or other distributions other than a dividend payable in shares of common stock or a subdivision of the outstanding shares of common stock (by reclassification or
otherwise), declared on the common stock since the immediately preceding Quarterly Dividend Payment Date, or, with respect to the first Quarterly Dividend Payment Date, since the first issuance of any
share or fraction of a share of Series&nbsp;C-1 Preferred Stock. The multiple of cash and non-cash dividends declared on the common stock to which holders of the
Series&nbsp;C-1 Preferred Stock are entitled, which shall be 10,000 initially but which shall be adjusted from time to time as hereinafter provided, is hereinafter referred to as the
"Dividend Multiple." In the event the Corporation shall at any time after November&nbsp;5, 2004 (the "Rights Declaration Date") (i)&nbsp;declare or pay any dividend on common stock payable in
shares of common stock, or (ii)&nbsp;effect a subdivision or combination or consolidation of the outstanding shares of common stock (by reclassification or otherwise than by payment of a dividend in
shares of common stock) into a greater or lesser number of shares of common stock, then in each such case the Dividend </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>2-A</FONT></P>

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<P><FONT SIZE=2>Multiple
thereafter applicable to the determination of the amount of dividends which holders of shares of Series&nbsp;C-1 Preferred Stock shall be entitled to receive shall be the
Dividend Multiple applicable immediately prior to such event multiplied by a fraction, the numerator of which is the number of shares of common stock outstanding immediately after such event and the
denominator of which is the number of shares of common stock that were outstanding immediately prior to such event. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;&nbsp;Notwithstanding
anything else contained in this paragraph&nbsp;(A), the Corporation shall, out of funds legally available for that purpose, declare a dividend or
distribution on the Series&nbsp;C-1 Preferred Stock as provided in this paragraph&nbsp;(A) immediately after it declares a dividend or distribution on the common stock (other than a
dividend payable in shares of common stock); provided that, in the event no dividend or distribution shall have been declared on the common stock during the period between any Quarterly Dividend
Payment Date and the next subsequent Quarterly Dividend Payment Date, a dividend of $1.00 per share on the Series&nbsp;C-1 Preferred Stock shall nevertheless be payable on such
subsequent Quarterly Dividend Payment Date. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(B)
Dividends shall begin to accrue and be cumulative on outstanding shares of Series&nbsp;C-1 Preferred Stock from the Quarterly Dividend Payment Date next preceding the
date of issue of such shares of Series&nbsp;C-1 Preferred Stock, unless the date of issue of such shares is prior to the record date for the first Quarterly Dividend Payment Date, in
which case dividends on such shares shall begin to accrue from the date of issue of such shares, or unless the date of issue is a Quarterly Dividend Payment Date or is a date after the record date for
the determination of holders of shares of Series&nbsp;C-1 Preferred Stock entitled to receive a quarterly dividend and before such Quarterly Dividend Payment Date, in either of which
events such dividends shall begin to accrue and be cumulative from such Quarterly Dividend Payment Date. Accrued but unpaid dividends shall not bear interest. Dividends paid on the shares of
Series&nbsp;C-1 Preferred Stock in an amount less than the total amount of such dividends at the time accrued and payable on such shares shall be allocated pro rata on a
share-by-share basis among all such shares at the time outstanding. The Board of Directors may fix in accordance with applicable law a record date for the determination of
holders of shares of Series&nbsp;C-1 Preferred Stock entitled to receive payment of a dividend or distribution declared thereon, which record date shall be not more than such number of
days prior to the date fixed for the payment thereof as may be allowed by applicable law. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;3.
</FONT><FONT SIZE=2><I>Voting Rights.</I></FONT><FONT SIZE=2> In addition to any other voting rights required by law, the holders of shares of
Series&nbsp;C-1 Preferred Stock shall have the following voting rights: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(A)
Subject to the provision for adjustment hereinafter set forth, each share of Series&nbsp;C-1 Preferred Stock shall entitle the holder thereof to 10,000 votes on all
matters submitted to a vote of the stockholders of the Corporation. The number of votes which a holder of a share of Series&nbsp;C-1 Preferred Stock is entitled to cast, which shall
initially be 10,000 but which may be adjusted from time to time as hereinafter provided, is hereinafter referred to as the "Vote Multiple." In the event the Corporation shall at any time after the
Rights Declaration Date (i)&nbsp;declare or pay any dividend on common stock payable in shares of common stock, or (ii)&nbsp;effect a subdivision or combination or consolidation of the outstanding
shares of common stock (by reclassification or otherwise than by payment of a dividend in shares of common stock) into a greater or lesser number of shares of common stock, then in each such case the
Vote Multiple thereafter applicable to the determination of the number of votes per share to which holders of shares of Series&nbsp;C-1 Preferred Stock shall be entitled shall be the
Vote Multiple immediately prior to such event multiplied by a fraction, the numerator of which is the number of shares of common stock outstanding immediately after such event and the denominator of
which is the number of shares of common stock that were outstanding immediately prior to such event. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(B)
Except as otherwise provided herein or by law, the holders of shares of Series&nbsp;C-1 Preferred Stock and the holders of shares of common stock and the holders of
shares of any other capital stock </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>3-A</FONT></P>

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<P><FONT SIZE=2>of
this Corporation having general voting rights, shall vote together as one class on all matters submitted to a vote of stockholders of the Corporation. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(C)
Except as otherwise required by applicable law or as set forth herein, holders of Series&nbsp;C-1 Preferred Stock shall have no special voting rights and their consent
shall not be required (except to the extent they are entitled to vote with holders of common stock as set forth herein) for taking any corporate action. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;4.
</FONT><FONT SIZE=2><I>Certain Restrictions.</I></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(A)
Whenever dividends or distributions payable on the Series&nbsp;C-1 Preferred Stock as provided in Section&nbsp;2 are in arrears, thereafter and until all accrued and
unpaid dividends and distributions, whether or not declared, on shares of Series&nbsp;C-1 Preferred Stock outstanding shall have been paid in full, the Corporation shall not: </FONT></P>

<UL>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(i)</FONT></DT><DD><FONT SIZE=2>declare
or pay dividends on, make any other distributions on, or redeem or purchase or otherwise acquire for consideration any shares of stock ranking junior (either as
to dividends or upon liquidation, dissolution or winding up) to the Series&nbsp;C-1 Preferred Stock;
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>(ii)</FONT></DT><DD><FONT SIZE=2>declare
or pay dividends on or make any other distributions on any shares of stock ranking on a parity (either as to dividends or upon liquidation, dissolution or
winding up) with the Series&nbsp;C-1 Preferred Stock, except dividends paid ratably on the Series&nbsp;C-1 Preferred Stock and all such parity stock on which dividends are
payable or in arrears in proportion to the total amounts to which the holders of all such shares are then entitled;
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>(iii)</FONT></DT><DD><FONT SIZE=2>except
as permitted in subsection 4(A)(iv)&nbsp;below, redeem, purchase or otherwise acquire for consideration shares of any stock ranking on a parity (either as to
dividends or upon liquidation, dissolution or winding up) with the Series&nbsp;C-1 Preferred Stock, provided that the Corporation may at any time redeem, purchase or otherwise acquire
shares of any such parity stock in exchange for shares of any stock of the Corporation ranking junior (either as to dividends or upon dissolution, liquidation or winding up) to the
Series&nbsp;C-1 Preferred Stock; or
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>(iv)</FONT></DT><DD><FONT SIZE=2>purchase
or otherwise acquire for consideration any shares of Series&nbsp;C-1 Preferred Stock, or any shares of any stock ranking on a parity (either as
to dividends or upon liquidation, dissolution or winding up) with the Series&nbsp;C-1 Preferred Stock, except in accordance with a purchase offer made in writing or by publication (as
determined by the Board of Directors) to all holders of such shares upon such terms as the Board of Directors, after consideration of the respective annual dividend rates and other relative rights and
preferences of the respective series and classes, shall determine in good faith will result in fair and equitable treatment among the respective series or classes. </FONT></DD></DL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(B)
The Corporation shall not permit any subsidiary of the Corporation to purchase or otherwise acquire for consideration any shares of stock of the Corporation unless the Corporation
could, under subsection (A)&nbsp;of this Section&nbsp;4, purchase or otherwise acquire such shares at such time and in such manner. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;5.
</FONT><FONT SIZE=2><I>Reacquired Shares.</I></FONT><FONT SIZE=2> Any shares of Series&nbsp;C-1 Preferred Stock purchased or otherwise acquired by the
Corporation in any manner whatsoever shall be retired and canceled promptly after the acquisition thereof. All such shares shall upon their cancellation become authorized but unissued shares of
preferred stock and may be reissued as part of a new series of preferred stock to be created by resolution or resolutions of the Board of Directors, subject to the conditions and restrictions on
issuance set forth herein. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;6.
</FONT><FONT SIZE=2><I>Liquidation, Dissolution or Winding Up.</I></FONT><FONT SIZE=2> Upon any liquidation (voluntary or otherwise), dissolution or winding up of the
Corporation, no distribution shall be made (x)&nbsp;to the holders of shares of stock ranking junior (either as to dividends or upon liquidation, dissolution or winding up) to the </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>4-A</FONT></P>

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<P><FONT SIZE=2>Series&nbsp;C-1
Preferred Stock unless, prior thereto, the holders of shares of Series&nbsp;C-1 Preferred Stock shall have received an amount equal to accrued and unpaid
dividends and distributions thereon, whether or not declared, to the date of such payment, plus an amount equal to the greater of (1)&nbsp;$10,000.00 per share or (2)&nbsp;an aggregate amount per
share, subject to the provision for adjustment hereinafter set forth, equal to 10,000 times the aggregate amount to be distributed per share to holders of common stock, or (y)&nbsp;to the holders of
stock ranking on a parity (either as to dividends or upon liquidation, dissolution or winding up) with the Series&nbsp;C-1 Preferred Stock, except distributions made ratably on the
Series&nbsp;C-1 Preferred Stock and all other such parity stock in proportion to the total amounts to which the holders of all such shares are entitled upon such liquidation, dissolution
or winding up. In the event the Corporation shall at any time after the Rights Declaration Date (i)&nbsp;declare or pay any dividend on common stock payable in shares of common stock, or
(ii)&nbsp;effect a subdivision or combination or consolidation of the outstanding shares of common stock (by reclassification or otherwise than by payment of a dividend in shares of common stock)
into a greater or lesser number of shares of common stock, then in each such case the aggregate amount per share to which holders of shares of Series&nbsp;C-1 Preferred Stock were
entitled immediately prior to such event under clause&nbsp;(x) of the preceding sentence shall be adjusted by multiplying such amount by a fraction, the numerator of which is the number of shares of
common stock outstanding immediately after such event and the denominator of which is the number of shares of common stock that were outstanding immediately prior to such event. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Neither
the consolidation of nor merging of the Corporation with or into any other corporation or corporations, nor the sale or other transfer of all or substantially all of the assets
of the Corporation, shall be deemed to be a liquidation, dissolution or winding up of the Corporation within the meaning of this Section&nbsp;6. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;7.
</FONT><FONT SIZE=2><I>Consolidation, Merger, etc.</I></FONT><FONT SIZE=2> In case the Corporation shall enter into any consolidation, merger, combination or other
transaction in which the shares of common stock are exchanged for or changed into other stock or securities, cash and/or any other property, then in any such case the shares of
Series&nbsp;C-1 Preferred Stock shall at the same time be similarly exchanged or changed in an amount per share (subject to the provision for adjustment hereinafter set forth) equal to
10,000 times the aggregate amount of stock, securities, cash and/or any other property (payable in kind), as the case may be, into which or for which each share of common stock is changed or
exchanged, plus accrued and unpaid dividends, if any, payable with respect to the Series&nbsp;C-1 Preferred Stock. In the event the Corporation shall at any time after the Rights
Declaration Date (i)&nbsp;declare or pay any dividend on common stock payable in shares of common stock, or (ii)&nbsp;effect a subdivision or combination or consolidation of the outstanding shares
of common stock (by reclassification or otherwise than by payment of a dividend in shares of common stock) into a greater or lesser number of shares of common stock, then in each such case the amount
set forth in the preceding sentence with respect to the exchange or change of shares of Series&nbsp;C-1 Preferred Stock shall be adjusted by multiplying such amount by a fraction, the
numerator of which is the number of shares of common stock outstanding immediately after such event and the denominator of which is the number of shares of common stock that were outstanding
immediately prior to such event. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;8.
</FONT><FONT SIZE=2><I>Redemption.</I></FONT><FONT SIZE=2> The shares of Series&nbsp;C-1 Preferred Stock shall not be redeemable; provided, however, that
the foregoing shall not limit the ability of the Corporation to purchase or otherwise deal in such shares to the extent otherwise permitted hereby and by law. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;9.
</FONT><FONT SIZE=2><I>Ranking.</I></FONT><FONT SIZE=2> Unless otherwise expressly provided in the Certificate of Incorporation or a Certificate of Designations
relating to any other series of preferred stock of the Corporation, the Series&nbsp;C-1 Preferred Stock shall rank junior to every other series of the Corporation's preferred stock
previously or hereafter authorized, as to the payment of dividends and the distribution of assets on liquidation, dissolution or winding up and shall rank senior to the common stock. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>5-A</FONT></P>

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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;10.
</FONT><FONT SIZE=2><I>Amendment.</I></FONT><FONT SIZE=2> The Certificate of Incorporation and this Certificate of Designations shall not be amended in any manner
which would materially alter or change the powers, preferences or special rights of the Series&nbsp;C-1 Preferred Stock so as to affect them adversely without the affirmative vote of the
holders of two-thirds or more of the outstanding shares of Series&nbsp;C-1 Preferred Stock, voting separately as a class. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;11.
</FONT><FONT SIZE=2><I>Fractional Shares.</I></FONT><FONT SIZE=2> Series&nbsp;C-1 Preferred Stock may be issued in whole shares or in any fraction of a
share that is one ten-thousandth (1/10,000th) of a share or any integral multiple of such fraction, which shall entitle the holder, in proportion to such holder's fractional shares, to
exercise voting rights, receive dividends, participate in distributions and to have the benefit of all other rights of holders of Series&nbsp;C-1 Preferred Stock. In lieu of fractional
shares, the Corporation may elect to make a cash payment as provided in the Rights Agreement for fractions of a share other than one ten-thousandth (1/10,000th) of a share or any integral
multiple thereof. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>6-A</FONT></P>

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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;I,
<U>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</U>,
<U>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</U>, do make this certificate, hereby declaring and certifying that this is my act and deed on
behalf of the Corporation this <U>&nbsp;&nbsp;&nbsp;&nbsp;</U> day of November, 2004. </FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=2>7-A</FONT></P>

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<FONT SIZE=2><A HREF="#toc_ke2260_1">Exhibit 3.1</A></FONT><BR>
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<TYPE>EX-4.1
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<DESCRIPTION>EXHIBIT 4.1
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<BR></FONT><FONT SIZE=2><B>Exhibit 4.1    <BR>    </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=3><B>AVANT IMMUNOTHERAPEUTICS,&nbsp;INC.<BR>
AND<BR>
EQUISERVE TRUST COMPANY, N.A.<BR>
AS RIGHTS AGENT<BR>
SHAREHOLDER RIGHTS AGREEMENT<BR>
DATED AS OF NOVEMBER&nbsp;5, 2004  </B></FONT></P>

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<TH WIDTH="13%" ALIGN="LEFT"><FONT SIZE=1><B>Section<BR> </B></FONT><HR NOSHADE></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="77%" ALIGN="LEFT"><FONT SIZE=1>&nbsp;</FONT><BR></TH>
<TH WIDTH="3%"><FONT SIZE=1>&nbsp;</FONT></TH>
<TH WIDTH="5%" ALIGN="CENTER"><FONT SIZE=1><B>Page</B></FONT><HR NOSHADE></TH>
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<TD WIDTH="13%"><FONT SIZE=2><B>Section 1.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B>Certain Definitions</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B>1</B></FONT></TD>
</TR>
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<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 2.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Appointment of Rights Agent</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
6</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 3.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Issue of Right Certificates</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
6</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 4.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Form of Right Certificates</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
8</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 5.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Countersignature and Registration</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
9</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 6.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Transfer, Split Up, Combination and Exchange of Right Certificates; Mutilated, Destroyed, Lost or Stolen Right Certificates</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
9</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 7.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Exercise of Rights; Exercise Price; Expiration Date of Rights</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
10</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 8.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Cancellation and Destruction of Right Certificates</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
12</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 9.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Reservation and Availability of Preferred Stock</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
12</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 10.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Preferred Stock Record Date</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
13</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 11.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Adjustment of Exercise Price, Number and Kind of Shares or Number of Rights</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
13</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 12.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Certificate of Adjusted Exercise Price or Number of Shares</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
20</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 13.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Consolidation, Merger or Sale or Transfer of Assets or Earning Power</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
21</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 14.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Fractional Rights and Fractional Shares</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
23</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 15.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Rights of Action</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
23</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 16.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Agreement of Right Holders</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
24</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 17.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Right Certificate Holder Not Deemed a Shareholder</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
24</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 18.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Concerning the Rights Agent</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
25</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 19.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Merger or Consolidation or Change of Name of Rights Agent</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
25</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 20.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Duties of Rights Agent</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
26</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 21.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Change of Rights Agent</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
28</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 22.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Issuance of New Right Certificates</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
28</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 23.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Redemption</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
29</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 24.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Exchange</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
29</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 25.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Notice of Certain Events</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
31</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 26.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Notices</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
32</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 27.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Supplements and Amendments</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
32</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 28.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Successors</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
33</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 29.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Determinations and Actions by the Board of Directors</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
33</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 30.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Benefits of this Agreement</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
33</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 31.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Severability</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
33</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="5%"><FONT SIZE=2>&nbsp;</FONT></TD>
</TR>
</TABLE>

<!-- insert table folio -->
<BR>
<P ALIGN="CENTER"><FONT SIZE=2>i</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<TABLE WIDTH="80%" BORDER=0 CELLSPACING=0 CELLPADDING=0>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 32.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Governing Law</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
34</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 33.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Counterparts</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
34</B></FONT></TD>
</TR>
<TR BGCOLOR="#CCEEFF" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 34.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Descriptive Headings</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
34</B></FONT></TD>
</TR>
<TR BGCOLOR="White" VALIGN="TOP">
<TD WIDTH="13%"><FONT SIZE=2><B><BR>
Section 35.</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="77%"><FONT SIZE=2><B><BR>
Force Majeure</B></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><B><BR>&nbsp;</B></FONT></TD>
<TD WIDTH="5%" ALIGN="RIGHT"><FONT SIZE=2><B><BR>
34</B></FONT></TD>
</TR>
</TABLE>
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<!-- User-specified TAGGED TABLE -->
<TABLE WIDTH="79%" BORDER=0 CELLSPACING=0 CELLPADDING=0>
<TR VALIGN="TOP">
<TD WIDTH="14%"><FONT SIZE=2>Exhibit A&#151;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="83%"><FONT SIZE=2>Certificate of Designations of<BR>
Series C-1 Junior Participating<BR>
Cumulative Preferred Stock</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="14%"><FONT SIZE=2><BR>
Exhibit B&#151;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="83%"><FONT SIZE=2><BR>
Form of Right Certificate</FONT></TD>
</TR>
</TABLE>
<!-- end of user-specified TAGGED TABLE -->

<P ALIGN="CENTER"><FONT SIZE=2>ii</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<!-- THIS IS THE END OF A COMPOSITION COMPONENT -->
<P ALIGN="CENTER"><FONT SIZE=2><B>SHAREHOLDER RIGHTS AGREEMENT  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Agreement, dated as of November&nbsp;5, 2004, between AVANT Immunotherapeutics,&nbsp;Inc., a Delaware corporation (the "Company"), and EquiServe Trust
Company, N.A., a national trust company (the "Rights Agent"). </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>W
I T N E S S E T H </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;WHEREAS,
the Board of Directors of the Company desires to provide shareholders of the Company with the opportunity to benefit from the long-term prospects and value of the
Company and to ensure that shareholders of the Company receive fair and equal treatment in the event of any proposed takeover of the Company; and </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;WHEREAS,
on November&nbsp;10, 1994, the Board of Directors of the Company authorized the Shareholder Rights Agreement dated as of November&nbsp;10, 1994 between the Company and State
Street Bank and Trust Company, as Rights Agent (the "1994 Rights Agreement"), declared a dividend distribution of one Right (as such term is defined in the 1994 Rights Agreement) for each outstanding
share of Common Stock, par value $.001 per share, of the Company (the "Common Stock") outstanding as of the close of business on November&nbsp;29, 1994 (the "1994 Record Date"), and authorized the
issuance of one Right for each share of Common Stock of the Company issued between the 1994 Record Date and the earlier of the Distribution Date or the Expiration Date (as such terms are defined in
the 1994 Rights Agreement), each Right initially representing the right to purchase one one-thousandth of a share of Series&nbsp;C-1 Junior Participating Cumulative Preferred
Stock of the Company upon the terms and subject to the conditions set forth in the 1994 Rights Agreement; and </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;WHEREAS,
on November&nbsp;5, 2004, the Board of Directors of the Company determined it desirable and in the best interests of the Company and its shareholders for the Company to extend
the benefits afforded by the 1994 Rights Agreement and to implement such extension by executing this Agreement; and </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;WHEREAS,
on November&nbsp;5, 2004 the Board of Directors of the Company authorized and declared a dividend distribution of one Right (as such term is hereinafter defined) for each
share of Common Stock outstanding as of November&nbsp;11, 2004 (the "Record Date"), and authorized the issuance of one Right for each share of Common Stock of the Company issued (whether or not
originally issued or sold from the Company's treasury, except in the case of treasury shares having associated Rights) between the Record Date and the earliest of the Distribution Date, Redemption
Date, Exchange Date or Final
Expiration Date (as such terms are hereinafter defined), each Right initially representing the right to purchase one ten-thousandth of a share of Series&nbsp;C-1 Junior
Participating Cumulative Preferred Stock of the Company having the rights, powers and preferences set forth on </FONT><FONT SIZE=2><I>Exhibit&nbsp;A</I></FONT><FONT SIZE=2> hereto, upon the terms
and subject to the conditions hereinafter set forth (the "Rights"); and </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;WHEREAS,
the Company desires to appoint the Rights Agent to act as rights agent hereunder, in accordance with the terms and conditions hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;NOW,
THEREFORE, in consideration of the premises and the mutual agreements herein set forth, the parties hereby agree as follows: </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;1.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Certain Definitions.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;For purposes of this Agreement, the following terms have the meanings
indicated: </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Acquiring Person"</I></FONT><FONT SIZE=2> shall mean any Person (as such term is hereinafter defined) who or which, together with all Affiliates
(as such term is hereinafter defined) and Associates (as such term is hereinafter defined) of such Person, shall be the Beneficial Owner (as such term is hereinafter defined) of 15% or more of the
shares of Common Stock of the Company then outstanding, but shall not include (i)&nbsp;the Company, (ii)&nbsp;any Subsidiary (as such term is hereinafter defined) of the Company, (iii)&nbsp;any
employee benefit plan or compensation arrangement of the Company or any Subsidiary of the Company or (iv)&nbsp;any Person holding shares of Common Stock of the Company organized, appointed or
established by the Company or any Subsidiary of the Company for or pursuant to the terms of any such employee benefit plan or compensation </FONT></P>

</UL>
<HR NOSHADE>
<P style='page-break-before:always'></p>
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<A NAME="page_ki2260_1_2"> </A>
<UL>

<P><FONT SIZE=2>arrangement
(the Persons described in clauses (i)&nbsp;through (iv)&nbsp;above are referred to herein as "Exempt Persons"); </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that
the term "Acquiring Person" shall not include any Grandfathered Person, unless such Grandfathered Person becomes the Beneficial Owner of a percentage of the shares of Common Stock of the Company then
outstanding equal to or exceeding such Grandfathered Person's Grandfathered Percentage. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Notwithstanding
the foregoing, no Person shall become an "Acquiring Person" as the result of an acquisition by the Company of Common Stock of the Company which, by reducing the number of
shares outstanding, increases the proportionate number of shares Beneficially Owned by such Person to 15% (or in the case of a Grandfathered Person, the Grandfathered Percentage applicable to such
Grandfathered Person) or more of the shares of Common Stock of the Company then outstanding; </FONT> <FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that if a Person shall become the Beneficial Owner of 15% (or in the case of a
Grandfathered Person, the Grandfathered Percentage
applicable to such Grandfathered Person) or more of the shares of Common Stock of the Company then outstanding by reason of share purchases by the Company and shall, after such share purchases by the
Company, become the Beneficial Owner of any additional shares (other than pursuant to a stock split, stock dividend or similar transaction) of Common Stock of the Company and immediately thereafter be
the Beneficial Owner of 15% (or in the case of a Grandfathered Person, the Grandfathered Percentage applicable to such Grandfathered Person) or more of the shares of Common Stock of the Company then
outstanding, then such Person shall be deemed to be an "Acquiring Person." </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In
addition, notwithstanding the foregoing, and notwithstanding anything to the contrary provided in the Agreement including without limitation in Sections 1(jj), 3(a) or 27, a Person
shall not be an "Acquiring Person" if the Board of Directors of the Company determines at any time that a Person who would otherwise be an "Acquiring Person," has become such without intending to
become an "Acquiring Person," and such Person divests as promptly as practicable (or within such period of time as the Board of Directors of the Company determines is reasonable) a sufficient number
of shares of Common Stock of the Company so that such Person would no longer be an "Acquiring Person," as defined pursuant to the foregoing provisions of this Section&nbsp;1(a). </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Adjustment Shares"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;11(a)(ii)&nbsp;hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Affiliate"</I></FONT><FONT SIZE=2> and </FONT><FONT SIZE=2><I>"Associate"</I></FONT><FONT SIZE=2> shall have the respective meanings ascribed
to such terms in Rule&nbsp;12b-2 of the General Rules and Regulations (the "Rules") under the Securities Exchange Act of 1934, as amended (the "Exchange Act"), as in effect on the date
of this Agreement; </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that no Person who is a director or officer of the Company shall be deemed an Affiliate or an Associate of any
other director or officer of the Company solely as a result of his or her position as director or officer of the Company. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d)&nbsp;&nbsp;&nbsp;A
Person shall be deemed the </FONT><FONT SIZE=2><I>"Beneficial Owner"</I></FONT><FONT SIZE=2> of, and shall be deemed to </FONT><FONT SIZE=2><I>"Beneficially
Own"</I></FONT><FONT SIZE=2> and have </FONT><FONT SIZE=2><I>"Beneficial Ownership"</I></FONT><FONT SIZE=2> of, any securities: </FONT></P>

<UL>
<UL>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;which
such Person or any of such Person's Affiliates or Associates, directly or indirectly, Beneficially Owns (as determined pursuant to Rule&nbsp;13d-3
of the Rules under the Exchange Act, as in effect on the date of this Agreement); </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;which
such Person or any of such Person's Affiliates or Associates, directly or indirectly, has: </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(A)&nbsp;&nbsp;the
right to acquire (whether or not such right is exercisable immediately or only after the passage of time or upon the satisfaction of any conditions or both) pursuant
to any agreement, arrangement or understanding (whether or not in writing) (other than customary agreements with and between underwriters and selling group members with respect to a bona fide public
offering of securities) or upon the exercise of conversion rights, exchange rights, rights (other than the Rights), warrants </FONT></P>

</UL>
</UL>
</UL>
</UL>
<P ALIGN="CENTER"><FONT SIZE=2>2</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<UL>
<UL>
<UL>
<UL>

<P><FONT SIZE=2>or
options, or otherwise; </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that a Person shall not be deemed the "Beneficial Owner" of, or to "Beneficially Own" or have "Beneficial
Ownership" of, (1)&nbsp;securities tendered pursuant to a tender or exchange offer made by or on behalf of such Person or any of such Person's Affiliates or Associates until such tendered securities
are accepted for purchase or exchange; (2)&nbsp;securities issuable upon exercise of Rights at any time prior to the occurrence of a Triggering Event; or (3)&nbsp;securities issuable upon exercise
of Rights from and after the occurrence of a Triggering Event, which Rights were acquired by such Person or any of such Person's Affiliates or Associates prior to the Distribution Date or pursuant to
Sections 3(a), 11(i)&nbsp;or 22 hereof; or </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(B)&nbsp;&nbsp;the
right to vote pursuant to any agreement, arrangement or understanding (whether or not in writing); </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2>
that a Person shall not be deemed the "Beneficial Owner" of, or to "Beneficially Own" or have "Beneficial Ownership" of, any security under this clause&nbsp;(B) if the agreement, arrangement or
understanding to vote such security (1)&nbsp;arises solely from a revocable proxy or consent given in response to a public proxy or consent solicitation made pursuant to a written proxy or consent
solicitation statement filed with the Securities and Exchange Commission in accordance with the Rules of the Exchange Act and (2)&nbsp;is not also then reportable by such person on
Schedule&nbsp;13D under the Exchange Act (or any comparable or successor report); or </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(C)&nbsp;&nbsp;the
right to dispose of pursuant to any agreement, arrangement or understanding (whether or not in writing) (other than customary arrangements with and between
underwriters and selling group members with respect to a bona fide public offering of securities); or </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii)&nbsp;&nbsp;which
are Beneficially Owned, directly or indirectly, by any other Person (or any Affiliate or Associate thereof) with which such Person or any of such Person's
Affiliates or Associates has any agreement, arrangement or understanding (whether or not in writing) (other than customary agreements with and between underwriters and selling group members with
respect to a bona fide public offering of securities) for the purpose of acquiring, holding, voting (except pursuant to a revocable proxy or consent as described in clause&nbsp;(B) of
Section&nbsp;1(d)(ii)&nbsp;hereof) or disposing of any securities of the Company; </FONT></P>

</UL>
</UL>
</UL>

<P><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that (1)&nbsp;no Person engaged in business as an underwriter of securities shall be deemed the Beneficial Owner of any securities
acquired through such Person's participation as an underwriter in good faith in a firm commitment underwriting until the expiration of forty (40)&nbsp;days after the date of such acquisition, and
(2)&nbsp;no Person who is a director or an officer of the Company shall be deemed, as a result of his or her position as director or officer of the Company, the Beneficial Owner
of any securities of the Company that are Beneficially Owned by any other director or officer of the Company. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;For
all purposes of this Agreement, the phrase "then outstanding," when used with reference to the percentage of the then outstanding securities Beneficially Owned by a Person, shall
mean the number of securities then issued and outstanding together with the number of such securities not then actually issued and outstanding which such Person would be deemed to Beneficially Own
hereunder. </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(e)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Business Day"</I></FONT><FONT SIZE=2> shall mean any day other than a Saturday, Sunday, or a day on which banking institutions in the State of
New York are authorized or obligated by law or executive order to close. </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>3</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(f)&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Certificate of Incorporation"</I></FONT><FONT SIZE=2> when used in reference to the Company shall mean the Third Restated Certificate of
Incorporation, as may be amended from time to time, of the Company. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(g)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Close of Business"</I></FONT><FONT SIZE=2> on any given date shall mean 5:00&nbsp;p.m., Boston, Massachusetts time, on such date; </FONT> <FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that if such date is not a Business Day it
shall mean 5:00&nbsp;p.m., Boston, Massachusetts time, on the next succeeding Business
Day. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(h)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Common Stock"</I></FONT><FONT SIZE=2> when used in reference to the Company shall mean the common stock, par value $0.001 per share, of the
Company or any other shares of capital stock of the Company into which such stock shall be reclassified or changed. "Common Stock" when used with reference to any Person other than the Company
organized in corporate form shall mean (i)&nbsp;the capital stock or other equity interest of such Person with the greatest voting power, (ii)&nbsp;the equity securities or other equity interest
having power to control or direct the management of such Person or (iii)&nbsp;if such Person is a Subsidiary of another Person, the Person or Persons which ultimately control such first-mentioned
Person and which have issued any such outstanding capital stock, equity securities or equity interest. "Common Stock" when used with reference to any Person not organized in corporate form shall mean
units of beneficial interest which (x)&nbsp;shall represent the right to participate generally in the profits and losses of such Person (including without limitation any flow-through tax
benefits resulting from an ownership interest in such Person) and (y)&nbsp;shall be entitled to exercise the greatest voting power of such Person or, in the case of a limited partnership, shall have
the power to remove or otherwise replace the general partner or partners. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Common Stock Equivalents"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;11(a)(iii)&nbsp;hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(j)&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Current Value"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;11(a)(iii)&nbsp;hereof. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(k)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Depositary Agent"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;7(c) hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(l)&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Distribution Date"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;3(a) hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(m)&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Exchange Date"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;7(a) hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(n)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Exempt Person"</I></FONT><FONT SIZE=2> shall have the meaning set forth in the definition of "Acquiring Person." </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(o)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Exercise Price"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;4(a) hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(p)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Expiration Date"</I></FONT><FONT SIZE=2> and </FONT><FONT SIZE=2><I>"Final Expiration Date"</I></FONT><FONT SIZE=2> shall have the meanings set
forth in Section&nbsp;7(a) hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(q)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Fair Market Value"</I></FONT><FONT SIZE=2> of any securities or other property shall be as determined in accordance with Section&nbsp;11(d)
hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(r)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Grandfathered Percentage"</I></FONT><FONT SIZE=2> shall mean, with respect to any Grandfathered Person, the percentage of the outstanding shares
of Common Stock of the Company that such Grandfathered Person, together with all Affiliates and Associates of such Grandfathered Person, Beneficially Owns as of the Grandfathered Time, plus an
additional <SUP>1</SUP>/<SMALL>2</SMALL>%; provided, however, that, in the event any Grandfathered Person shall sell, transfer, or otherwise dispose of any outstanding shares of Common Stock of the Company after
the Grandfathered Time, the Grandfathered Percentage shall, subsequent to such sale, transfer or disposition, mean, with respect to such Grandfathered Person, the lesser of (i)&nbsp;the
Grandfathered Percentage as in effect immediately prior to such sale, transfer or disposition or (ii)&nbsp;the percentage of outstanding shares of Common Stock of the Company that such Grandfathered
Person Beneficially Owns immediately following such sale, transfer or disposition, plus an additional <SUP>1</SUP>/<SMALL>2</SMALL>%. </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>4</FONT></P>

<HR NOSHADE>
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<A NAME="page_ki2260_1_5"> </A>
<UL>
<BR>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(s)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Grandfathered Person"</I></FONT><FONT SIZE=2> shall mean any Person who or which, together with all Affiliates and Associates of such Person,
is, as of the Grandfathered Time, the Beneficial Owner of 15% or more of
the shares of Common Stock of the Company then outstanding. Notwithstanding anything to the contrary provided in this Agreement, any Grandfathered Person who after the Grandfathered Time becomes the
Beneficial Owner of less than 15% of the shares of Common Stock of the Company then outstanding shall cease to be a Grandfathered Person and shall be subject to all of the provisions of this Agreement
in the same manner as any Person who is not and was not a Grandfathered Person. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(t)&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Grandfathered Time"</I></FONT><FONT SIZE=2> shall mean [9:00&nbsp;a.m.], Boston, Massachusetts time, on
November&nbsp;6, 2004. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(u)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Group"</I></FONT><FONT SIZE=2> shall have the meaning set forth in clause&nbsp;(b) of the definition of "Person." </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(v)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Person"</I></FONT><FONT SIZE=2> shall mean (a)&nbsp;an individual, a corporation, a partnership, a limited liability company, an association,
a joint stock company, a trust, a business trust, a government or political subdivision, any unincorporated organization, or any other association or entity including any successor (by merger or
otherwise) thereof or thereto, and (b)&nbsp;a "group" as that term is used for purposes of Section&nbsp;13(d)(3) of the Securities Exchange Act of 1934, as amended. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(w)&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Preferred Stock"</I></FONT><FONT SIZE=2> shall mean shares of Series&nbsp;A Junior Participating Cumulative Preferred Stock, par value $0.01
per share, of the Company having the rights and preferences set forth in the form of Certificate of Designations attached hereto as Exhibit&nbsp;A. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(x)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Preferred Stock Equivalents"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;11(b) hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(y)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Principal Party"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;13(b) hereof. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(z)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Redemption Date"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;7(a) hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(aa)&nbsp;</FONT><FONT
SIZE=2><I>"Redemption Price"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;23 hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(bb)&nbsp;</FONT><FONT
SIZE=2><I>"Registered Common Stock"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;13(b) hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(cc)&nbsp;</FONT><FONT
SIZE=2><I>"Right Certificate"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;3(a) hereof. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(dd)&nbsp;</FONT><FONT
SIZE=2><I>"Section&nbsp;11(a)(ii)&nbsp;Event"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;11(a)(ii)&nbsp;hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ee)&nbsp;</FONT><FONT
SIZE=2><I>"Section&nbsp;11(a)(ii)&nbsp;Trigger Date"</I></FONT><FONT SIZE=2> shall have the meaning set forth in
Section&nbsp;11(a)(iii)&nbsp;hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ff)&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Section&nbsp;13 Event"</I></FONT><FONT SIZE=2> shall mean any event described in clauses (x), (y)&nbsp;or (z)&nbsp;of
Section&nbsp;13(a) hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(gg)&nbsp;</FONT><FONT
SIZE=2><I>"Section&nbsp;24(a)(i)&nbsp;Exchange Ratio"</I></FONT><FONT SIZE=2> shall have the meaning set forth in
Section&nbsp;24(a)(i)&nbsp;hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(hh)&nbsp;</FONT><FONT
SIZE=2><I>"Section&nbsp;24(a)(ii)&nbsp;Exchange Ratio"</I></FONT><FONT SIZE=2> shall have the meaning set forth in
Section&nbsp;24(a)(ii)&nbsp;hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Spread"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;11(a)(iii)&nbsp;hereof. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(jj)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Stock Acquisition Date"</I></FONT><FONT SIZE=2> shall mean the date of the first public announcement (which for purposes of this definition
shall include, without limitation, the issuance of a press release or the filing of a publicly-available report or other document with the Securities and Exchange Commission or any other governmental
agency) by the Company, acting pursuant to a resolution adopted by the Board of Directors of the Company, or by an Acquiring Person, subject in each case to the last paragraph of Section&nbsp;1(a),
that an Acquiring Person has become such. </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>5</FONT></P>

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<UL>
<BR>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(kk)&nbsp;</FONT><FONT
SIZE=2><I>"Subsidiary"</I></FONT><FONT SIZE=2> shall mean, with reference to any Person, any corporation or other entity of which securities or other
ownership interests having ordinary voting power sufficient, in the absence of contingencies, to elect a majority of the board of directors or other persons performing similar functions of such
corporation or other entity are at the time directly or indirectly Beneficially Owned or otherwise controlled by such Person either alone or together with one or more Affiliates of such Person. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ll)&nbsp;&nbsp;&nbsp;</FONT><FONT
SIZE=2><I>"Substitution Period"</I></FONT><FONT SIZE=2> shall have the meaning set forth in Section&nbsp;11(a)(iii)&nbsp;hereof. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(mm)&nbsp;</FONT><FONT
SIZE=2><I>"Triggering Event"</I></FONT><FONT SIZE=2> shall mean any Section&nbsp;11(a)(ii)&nbsp;Event or any Section&nbsp;13 Event. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;2.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Appointment of Rights Agent.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The Company hereby appoints the Rights Agent to act as agent for
the Company and the holders of the Rights (who, in accordance with Section&nbsp;3 hereof, shall prior to the Distribution Date (as hereinafter defined in Section&nbsp;3(a)) also be the holders of
the Common Stock of the Company) in accordance with the terms and conditions hereof, and the Rights Agent hereby accepts such appointment. The Company may from time to time appoint such
Co-Rights Agents as it may deem necessary or desirable. In the event the Company appoints one or more Co-Rights Agents, the respective duties of the Rights Agent and any
Co-Rights Agents shall be as the Company shall determine. The Company shall give ten (10)&nbsp;days' prior written notice to the Rights Agent of the appointment of one or more
Co-Rights Agents and the respective duties of the Rights Agent and any such Co-Rights Agents. The Rights Agent shall have no duty to supervise, and shall in no event be liable
for, the acts or omissions of any such Co-Rights Agent. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;3.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Issue of Right Certificates.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;From
the date hereof until the earlier of (i)&nbsp;the Close of Business on the tenth calendar day after the Stock Acquisition Date or (ii)&nbsp;the Close of
Business on the tenth Business Day (or such later calendar day, if any, as the Board of Directors of the Company may determine in its sole discretion) after the date a tender or exchange offer by any
Person, other than an Exempt Person, is first published or sent or given within the meaning of Rule&nbsp;14d-4(a) of the Exchange Act, or any successor rule, if, upon consummation
thereof, such Person could become the Beneficial Owner of 15% (or in the case of a Grandfathered Person, the Grandfathered Percentage applicable to such Grandfathered Person) or more of the shares of
Common Stock of the Company then outstanding (including any such date which is after the date of this Agreement and prior to the issuance of the Rights) (the earliest of such dates being herein
referred to as the "Distribution Date"), (x)&nbsp;the Rights will be evidenced (subject to the provisions of Section&nbsp;3(b) hereof) by the certificates for the Common Stock of the Company
registered in the names of the holders of the Common Stock of the Company (which certificates for Common Stock of the Company shall be deemed also to be certificates for Rights) and not by separate
certificates, and (y)&nbsp;the Rights will be transferable only in connection with the transfer of the underlying shares of Common Stock of the Company. As soon as practicable after the Distribution
Date, the Rights Agent will, at the Company's expense send, by first-class, insured, postage prepaid mail, to each record holder of the Common Stock of the Company as of the Close of Business on the
Distribution Date, at the address of such holder shown on the records of the Company, one or more certificates, in substantially the form of </FONT> <FONT SIZE=2><I>Exhibit&nbsp;B</I></FONT><FONT SIZE=2> hereto (the "Right Certificates"), evidencing
one Right for each share of Common Stock of the Company so held, subject to adjustment as
provided herein. In the event that an adjustment in the number of Rights per share of Common Stock of the Company has been made pursuant to Section&nbsp;11(o) hereof, the Company may make the
necessary and appropriate rounding adjustments (in accordance with Section&nbsp;14(a) hereof) at the time of distribution of the Right Certificates, so that Right Certificates representing only
whole numbers of Rights are distributed and cash is paid in lieu of any fractional Rights. As of and after the Close of Business on the Distribution Date, the Rights will be evidenced solely by such
Right Certificates. </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>6</FONT></P>

<HR NOSHADE>
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<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;With
respect to certificates for the Common Stock of the Company issued prior to the Close of Business on the Record Date, the Rights will be evidenced by such
certificates for the Common Stock of the Company on or until the Distribution Date (or the earlier redemption, expiration or termination of the Rights), and the registered holders of the Common Stock
of the Company also shall be the registered holders of the associated Rights. Until the Distribution Date (or the earlier redemption, expiration or termination of the Rights), the transfer of any of
the certificates for the Common Stock of the Company outstanding prior to the date of this Agreement shall also constitute the transfer of the Rights associated with the Common Stock of the Company
represented by such certificate. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;&nbsp;Certificates
for the Common Stock of the Company issued after the Record Date, but prior to the earliest of the Distribution Date, Redemption Date, Exchange Date or
Final Expiration Date, shall be deemed also to be certificates for Rights, and shall bear a legend, substantially in the form set forth below: </FONT></P>

<UL>

<P><FONT SIZE=2>This
certificate also evidences and entitles the holder hereof to certain Rights as set forth in a Shareholder Rights Agreement between AVANT Immunotherapeutics,&nbsp;Inc. and EquiServe Trust
Company, N.A. (or any successor thereto), as Rights Agent, dated as of November&nbsp;5, 2004 as amended, restated, renewed, supplemented or extended from time to time (the "Rights Agreement"), the
terms of which are hereby incorporated herein by reference and a copy of which is on file at the principal offices of AVANT Immunotherapeutics,&nbsp;Inc. and the stock transfer administration office
of the Rights Agent. Under certain circumstances, as set forth in the Rights Agreement, such Rights will be evidenced by separate certificates and will no longer be evidenced by this certificate.
AVANT Immunotherapeutics,&nbsp;Inc. may redeem the Rights at a redemption price of $0.01 per Right, subject to adjustment, under the terms of the Rights Agreement. AVANT
Immunotherapeutics,&nbsp;Inc. will mail to the holder of this certificate a copy of the Rights Agreement, as in effect on the date of mailing, without charge promptly after receipt of a written
request therefor. Under certain circumstances, Rights issued to or held by Acquiring Persons or any Affiliates or Associates thereof (as defined in the Rights Agreement), and any subsequent holder of
such Rights, may become null and void. The Rights shall not be exercisable, and shall be void so long as held, by a holder in any jurisdiction where the requisite qualification, if any, to the
issuance to such holder, or the exercise by such holder, of the Rights in such jurisdiction shall not have been obtained or be obtainable. </FONT></P>

</UL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;With
respect to such certificates containing the foregoing legend, the Rights associated with the Common Stock of the Company represented by such certificates shall be evidenced by such
certificates alone until the earliest of the Distribution Date, Redemption Date, Exchange Date or Final Expiration Date, and the transfer of any of such certificates shall also constitute the transfer
of the Rights associated with the Common Stock of the Company represented by such certificates. In the event that the Company purchases or acquires any shares of Common Stock of the Company after the
Record Date but prior to the Distribution Date, any Rights associated with such Common Stock of the Company shall be deemed canceled and retired so that the Company shall not be entitled to exercise
any Rights associated with the shares of Common Stock of the Company which are no longer outstanding. The failure to print the foregoing legend on any such certificate representing Common Stock of the
Company or any defect therein shall not affect in any manner whatsoever the application or interpretation of the provisions of Section&nbsp;7(e) hereof. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>7</FONT></P>

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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;4.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Form of Right Certificates.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;The
Right Certificates (and the forms of election to purchase shares and of assignment and certificate to be printed on the reverse thereof) shall each be substantially
in the form of </FONT><FONT SIZE=2><I>Exhibit&nbsp;B</I></FONT><FONT SIZE=2> hereto and may have such marks of identification or designation and such legends, summaries or endorsements printed
thereon as the Company may deem appropriate and as are not inconsistent with the provisions of this Agreement, or as may be required to comply with any applicable law, rule or regulation or with any
rule or regulation of any stock exchange on which the Rights may from time to time be listed, or to conform to customary usage. The Right Certificates shall be in a machine printable format and in a
form reasonably satisfactory to the Rights Agent. Subject to the provisions of Section&nbsp;11 and Section&nbsp;22 hereof, the Right Certificates, whenever distributed, shall be dated as of the
Record Date, shall show the date of countersignature, and on their face shall entitle the holders thereof to purchase such number of one ten-thousandths of a share of Preferred Stock as
shall be set forth therein at the price set forth therein (the "Exercise Price"), but the number of such shares and the Exercise Price shall be subject to adjustment as provided herein. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;Any
Right Certificate issued pursuant to Section&nbsp;3(a) or Section&nbsp;22 hereof that represents Rights Beneficially Owned by (i)&nbsp;an Acquiring Person or
any Associate or Affiliate of an Acquiring Person, (ii)&nbsp;a transferee of an Acquiring Person (or of any Associate or Affiliate of an Acquiring Person) who becomes a transferee after the
Acquiring Person becomes such, or (iii)&nbsp;a transferee of an Acquiring Person (or of any such Associate or Affiliate) who becomes a transferee prior to or concurrently with the Acquiring Person
becoming such and receives such Rights pursuant to either (A)&nbsp;a transfer (whether or not for consideration) from the Acquiring Person to holders of equity interests in such Acquiring Person or
to any Person with whom the Acquiring Person has any continuing agreement, arrangement or understanding (whether or not in writing) regarding the transferred Rights, the shares of Common Stock of the
Company associated with such Rights or the Company or (B)&nbsp;a transfer which the Board of Directors of the Company has determined is part of a plan, arrangement or understanding which has as a
primary purpose or effect the avoidance of Section&nbsp;7(e) hereof, and any Right Certificate issued pursuant to Section&nbsp;6, Section&nbsp;11 or Section&nbsp;22 upon transfer, exchange,
replacement or adjustment of any other Right Certificate referred to in this sentence, shall have deleted therefrom the second
sentence of the existing legend on such Right Certificate and in substitution therefor shall contain the following legend: </FONT></P>

<UL>

<P><FONT SIZE=2>The
Rights represented by this Right Certificate are or were Beneficially Owned by a Person who was or became an Acquiring Person or an Affiliate or an Associate of an Acquiring Person (as such terms
are defined in the Rights Agreement). This Right Certificate and the Rights represented hereby may become null and void under certain circumstances as specified in Section&nbsp;7(e) of the Rights
Agreement. </FONT></P>

</UL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The
Company shall give notice to the Rights Agent promptly after it becomes aware of the existence and identity of any Acquiring Person or any Associate or Affiliate thereof. The Company
shall instruct the Rights Agent in writing of the Rights which should be so legended. The failure to print the foregoing legend on any such Right Certificate or any defect therein shall not affect in
any manner whatsoever the application or interpretation of the provisions of Section&nbsp;7(e) hereof. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>8</FONT></P>

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<P><FONT SIZE=2><A
NAME="page_kj2260_1_9"> </A> </FONT> <FONT SIZE=2>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;5.</FONT><FONT SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Countersignature and Registration.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;The
Right Certificates shall be executed on behalf of the Company by its Chairman of the Board of Directors, or its President or any Vice President and by its Treasurer
or any Assistant Treasurer, or by its Secretary or any Assistant Secretary, either manually or by facsimile signature, and shall have affixed thereto the Company's seal or a facsimile thereof which
shall be attested to by the Secretary or any Assistant Secretary of the Company, either manually or by facsimile signature. The Right Certificates shall be manually countersigned by an authorized
signatory of the Rights Agent and shall not be valid for any purpose unless so countersigned, and such countersignature upon any Right Certificate shall be conclusive evidence, and the only evidence,
that such Right Certificate has been duly countersigned as required hereunder. In case any officer of the Company who shall have signed any of the Right Certificates shall cease to be such officer of
the Company before countersignature by the Rights Agent and issuance and delivery by the Company, such Right Certificates, nevertheless, may be countersigned by an authorized signatory of the Rights
Agent, and issued and delivered by the Company with the same force and effect as though the person who signed such Right Certificates had not ceased to be such officer of the Company; and any Right
Certificates may be signed on behalf of the Company by any person who, at the actual date of the execution of such Right Certificate, shall be a proper officer of the Company to sign such Right
Certificate, although at the date of the execution of this Rights Agreement any such person was not such an officer. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;Following
the Distribution Date, the Rights Agent will keep or cause to be kept, at one of its offices designated as the appropriate place for surrender of Right
Certificates upon exercise or transfer, books for registration and transfer of the Right Certificates issued hereunder. Such books shall show the names and addresses of the respective holders of the
Right Certificates, the number of Rights evidenced on its face by each of the Right Certificates and the date of each of the Right Certificates. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;6.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Transfer, Split Up, Combination and Exchange of Right Certificates; Mutilated, Destroyed, Lost or Stolen Right
Certificates.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;Subject
to the provisions of Section&nbsp;4(b), Section&nbsp;7(e) and Section&nbsp;14 hereof, at any time after the Close of Business on the Distribution Date, and
at or prior to the Close of Business on the Expiration Date, any Right Certificate or Certificates may be transferred, split up, combined or exchanged for another Right Certificate or Certificates,
entitling the registered holder to purchase a like number of one ten-thousandths of a share of Preferred Stock (or following a Triggering Event, Common Stock of the Company, cash,
property, debt securities, Preferred Stock or any combination thereof, including any such securities, cash or property following a Section&nbsp;13 Event) as the Right Certificate or Certificates
surrendered then entitled such holder to purchase and at the same Exercise Price. Any registered holder desiring to transfer, split up, combine or exchange any Right Certificate shall make such
request in writing delivered to the Rights Agent, and shall surrender the Right Certificate or Certificates to be transferred, split up, combined or exchanged, with the form of assignment and
certificate duly executed, at the office or offices of the Rights Agent designated for such purpose. Neither the Rights Agent nor the Company shall be obligated to take any action whatsoever with
respect to the transfer of any such surrendered Right Certificate until the registered holder shall have completed and signed the certificate contained in the form of assignment on the reverse side of
such Right Certificate and shall have provided such additional evidence of the identity of the Beneficial Owner (or former Beneficial Owner) or Affiliates or Associates thereof as the Company shall
reasonably request. Thereupon the Rights Agent shall, subject to Section&nbsp;4(b), Section&nbsp;7(e) and Section&nbsp;14 hereof, countersign and deliver to the Person entitled thereto a Right
Certificate or Certificates, as the case may be, as so requested. The Company may require payment by the registered holder of a Right Certificate, of a sum </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>9</FONT></P>

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<UL>

<P><FONT SIZE=2>sufficient
to cover any tax or governmental charge that may be imposed in connection with any transfer, split up, combination or exchange of Right Certificates. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;Upon
receipt by the Company and the Rights Agent of evidence reasonably satisfactory to them of the loss, theft, destruction or mutilation of a Right Certificate, and,
in case of loss, theft or destruction, of indemnity or security satisfactory to them, and reimbursement to the Company and the Rights Agent of all reasonable expenses incidental thereto, and upon
surrender to the Rights Agent and cancellation of the Right Certificate, if mutilated, the Company will execute and deliver a new Right Certificate of like tenor to the Rights Agent for
countersignature and delivery to the registered owner in lieu of the Right Certificate so lost, stolen, destroyed or mutilated. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;7.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Exercise of Rights; Exercise Price; Expiration Date of Rights.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;Subject
to Section&nbsp;7(e) hereof, the registered holder of any Right Certificate may exercise the Rights evidenced thereby (except as otherwise provided herein) in
whole or in part at any time after the Distribution Date upon surrender of the Right Certificate, with the form of election to purchase and the certificate on the reverse side thereof duly executed,
to the Rights Agent at the office or offices of the Rights Agent designated for such purpose, together with payment of the aggregate Exercise Price for the total number of one
ten-thousandths of a share of Preferred Stock (or other securities, cash or other assets, as the case may be) as to which such surrendered Rights are then exercised, at or prior to the
earlier of (i)&nbsp;the Close of Business on the tenth anniversary of the Record Date (the "Final Expiration Date"), (ii)&nbsp;the time at which the Rights are redeemed as provided in
Section&nbsp;23 hereof (the "Redemption Date") or (iii)&nbsp;the time at which such Rights are exchanged as provided in Section&nbsp;24 hereof (the "Exchange Date") (the earliest of (i),
(ii)&nbsp;or (iii)&nbsp;being herein referred to as the "Expiration Date"). Except as set forth in Section&nbsp;7(e) hereof and notwithstanding any other provision of this Agreement, any Person
who prior to the Distribution Date becomes a record holder of shares of Common Stock of the Company may exercise all of the rights of a registered holder of a Right Certificate with respect to the
Rights associated with such shares of Common Stock of the Company in accordance with the provisions of this Agreement, as of the date such Person becomes a record holder of shares of Common Stock of
the Company. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;The
Exercise Price for each one ten-thousandth of a share of Preferred Stock pursuant to the exercise of a Right shall initially be Thirty-five United States
Dollars (U.S. $35.00), shall be subject to adjustment from time to time as provided in Section&nbsp;11 and Section&nbsp;13 hereof and shall be payable in lawful money of the United States of
America in accordance with Section&nbsp;7(c) below. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;&nbsp;As
promptly as practicable following the Distribution Date, the Company shall deposit with a corporation, trust, bank or similar institution in good standing organized
under the laws of the United States or any State of the United States, which is authorized under such laws to exercise corporate trust or stock transfer powers and is subject to supervision or
examination by a federal or state authority (such institution is hereinafter referred to as the "Depositary Agent"), certificates representing the shares of Preferred Stock that may be acquired upon
exercise of the Rights and the Company shall cause such Depositary Agent to enter into an agreement pursuant to which the Depositary Agent shall issue receipts representing interests in the shares of
Preferred Stock so deposited. Upon receipt of a Right Certificate representing exercisable Rights, with the form of election to purchase and the certificate on the reverse side thereof duly executed,
accompanied by payment of the Exercise Price for the shares to be purchased and an amount equal to any applicable transfer tax (as determined by the Rights Agent) by certified check or bank draft
payable to the order of the Company or by money order, the Rights Agent shall, subject to Section&nbsp;20(k) and Section&nbsp;14(b) hereof, thereupon promptly (i)&nbsp;requisition from the
Depositary </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>10</FONT></P>

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<UL>
<BR>

<P><FONT SIZE=2>Agent
(or make available, if the Rights Agent is the Depositary Agent) depositary receipts or certificates for the number of one ten-thousandths of a share of Preferred Stock to be
purchased and the Company hereby irrevocably authorizes the Depositary Agent to comply with all such requests, (ii)&nbsp;when appropriate, requisition from the Company the amount of cash, if any, to
be paid in lieu of issuance of fractional shares in accordance with Section&nbsp;14 hereof, (iii)&nbsp;promptly after receipt of such certificates or depositary receipts, cause the same to be
delivered to or upon the order of the registered holder of such Right Certificate, registered in such name or names as may be designated by such holder and (iv)&nbsp;when appropriate, after receipt
of each certificate or depositary receipts promptly deliver such cash to or upon the order of the registered holder of such Right Certificate. In the event that the Company is obligated to issue other
securities (including Common Stock of the Company) of the Company, pay cash or distribute other property pursuant to Section&nbsp;11(a) hereof, the Company will make all arrangements necessary so
that such other securities, cash or other property are available for distribution by the Rights Agent, if and when appropriate. The payment of the Exercise Price may be made by certified or bank check
payable to the order of the Company, or by money order or wire transfer of immediately available funds to the account of the Company (provided that notice of such wire transfer shall be given by the
holder of the related Right to the Rights Agent). </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d)&nbsp;&nbsp;&nbsp;In
case the registered holder of any Right Certificate shall exercise less than all the Rights evidenced thereby, a new Right Certificate evidencing Rights equivalent to
the Rights remaining unexercised shall be issued by the Rights Agent and delivered to the registered holder of such Right Certificate or to his duly authorized assigns, subject to the provisions of
Section&nbsp;14 hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(e)&nbsp;&nbsp;&nbsp;Notwithstanding
anything in this Agreement to the contrary, from and after the first occurrence of a Section&nbsp;11(a)(ii)&nbsp;Event or Section&nbsp;13 Event,
any Rights Beneficially Owned by (i)&nbsp;an Acquiring Person or any Associate or Affiliate of an Acquiring Person, (ii)&nbsp;a transferee of an Acquiring Person (or of any Associate or Affiliate
of an Acquiring Person) who becomes a transferee after the Acquiring Person becomes such or (iii)&nbsp;a transferee of an Acquiring Person (or of any Associate or Affiliate of an Acquiring Person)
who becomes a transferee prior to or concurrently with the Acquiring Person becoming such and receives such Rights pursuant to either (A)&nbsp;a transfer (whether or not for consideration) from the
Acquiring Person to holders of equity interests in such Acquiring Person or to any Person with whom the Acquiring Person has any continuing agreement, arrangement or understanding regarding the
transferred Rights, the shares of Common Stock of the Company associated with such Rights or the Company, or (B)&nbsp;a transfer which the Board of Directors of the Company has determined is part of
a plan, arrangement or understanding which has as a primary purpose or effect the avoidance of this Section&nbsp;7(e), shall be null and void without any further action and no holder of such Rights
shall have any rights whatsoever with respect to such Rights, whether under any provision of this Agreement or otherwise. The Company shall use all reasonable efforts to ensure that the provisions of
this Section&nbsp;7(e) and Section&nbsp;4(b) hereof are complied with, but shall have no liability to any holder of Right Certificates or other Person as a result of its failure to make any
determinations with respect to an Acquiring Person or any Affiliates or Associates of an Acquiring Person or any transferee of any of them hereunder. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(f)&nbsp;&nbsp;&nbsp;&nbsp;Notwithstanding
anything in this Agreement to the contrary, neither the Rights Agent nor the Company shall be obligated to undertake any action with respect to a
registered holder of Rights upon the occurrence of any purported exercise as set forth in this Section&nbsp;7 unless such registered holder shall have (i)&nbsp;completed and signed the certificate
contained in the form of election to purchase set forth on the reverse side of the Right Certificate surrendered for such exercise, and (ii)&nbsp;provided such additional evidence of the identity of
the Beneficial Owner (or </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>11</FONT></P>

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<P><FONT SIZE=2>former
Beneficial Owner) or Affiliates or Associates thereof as the Company shall reasonably request. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;8.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Cancellation and Destruction of Right Certificates.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;All Right Certificates surrendered for the
purpose of exercise, transfer, split up, combination or exchange shall, if surrendered to the Company or any of its agents, be delivered to the Rights Agent for cancellation or in canceled form, or,
if surrendered to the Rights Agent, shall be canceled by it, and no Right Certificates shall be issued in lieu thereof except as expressly permitted by any of the provisions of this Agreement. The
Company shall deliver to the Rights Agent for cancellation and retirement, and the Rights Agent shall so cancel and retire, any other Right Certificate purchased or acquired by the Company otherwise
than upon the exercise thereof. The Rights Agent shall deliver all canceled Right Certificates to the Company. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;9.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Reservation and Availability of Preferred Stock.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;The
Company covenants and agrees that it will cause to be reserved and kept available out of its authorized and unissued shares of Preferred Stock or any authorized and
issued shares of Preferred Stock held in its treasury, the number of shares of Preferred Stock that will be sufficient to permit the exercise in full of all outstanding and exercisable Rights. Upon
the occurrence of any events resulting in an increase in the aggregate number of shares of Preferred Stock issuable upon exercise of all outstanding Rights in excess of the number then reserved, the
Company shall make appropriate increases in the number of shares so reserved. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;The
Company shall use its best efforts to cause, from and after such time as the Rights become exercisable, all shares of Preferred Stock issued or reserved for issuance
to be listed, upon official notice of issuance, upon the principal national securities exchange, if any, upon which the Common Stock of the Company is listed or, if the principal market for the Common
Stock of the Company is not on any national securities exchange, to be eligible for quotation on the National Association of Securities Dealers Automated Quotation System ("NASDAQ") or any successor
thereto or other comparable quotation system. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;&nbsp;The
Company shall use its best efforts to (i)&nbsp;file, as soon as practicable following the earliest date after the occurrence of a
Section&nbsp;11(a)(ii)&nbsp;Event on which the consideration to be delivered by the Company upon exercise of the Rights has been determined in accordance with
Section&nbsp;11(a)(iii)&nbsp;hereof, or as soon as required by law following the Distribution Date, as the case may be, a registration statement under the Securities Act of 1933, as amended (the
"Securities Act"), with respect to the securities purchasable upon exercise of the Rights on an appropriate form, (ii)&nbsp;cause such registration statement to become effective as soon as
practicable after such filing and (iii)&nbsp;cause such registration statement to remain effective (with a prospectus that at all times meets the requirements of the Securities Act) until the
earlier of (A)&nbsp;the date as of which the Rights are no longer exercisable for such securities or (B)&nbsp;the Expiration Date. The Company will also take such action as may be appropriate
under, and which will ensure compliance with, the securities or "blue sky" laws of the various states in connection with the exercisability of the Rights. The Company may temporarily suspend, for a
period of time not to exceed ninety (90)&nbsp;days after the date determined in accordance with the provisions of the first sentence of this Section&nbsp;9(c), the exercisability of the Rights in
order to prepare and file such registration statement and permit it to become effective. Upon such suspension, the Company shall issue a public announcement stating that the exercisability of the
Rights has been temporarily suspended, as well as a public announcement at such time as the suspension is no longer in effect, in each case with prompt written notice to the Rights Agent.
Notwithstanding any such provision of this Agreement to the contrary, the Rights shall not be exercisable in any jurisdiction unless the requisite qualification in such jurisdiction shall have been
obtained. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d)&nbsp;&nbsp;&nbsp;The
Company covenants and agrees that it will take all such action as may be necessary to ensure that all shares of Preferred Stock delivered upon the exercise of the
Rights shall, at the </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>12</FONT></P>

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<A NAME="page_kj2260_1_13"> </A>
<UL>
<BR>

<P><FONT SIZE=2>time
of delivery of the certificates or depositary receipts for such shares (subject to payment of the Exercise Price), be duly and validly authorized and issued and fully paid and nonassessable. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(e)&nbsp;&nbsp;&nbsp;The
Company further covenants and agrees that it will pay when due and payable any and all federal and state transfer taxes and charges which may be payable in respect
of the issuance or delivery of the Right Certificates or of any certificates for shares of Preferred Stock and/or other property upon the exercise of Rights. The Company shall not, however, be
required to pay any transfer tax which may be payable in respect of any transfer or delivery of Right Certificates or the issuance or delivery of other securities or property to a person other than,
or in respect of the issuance or delivery of securities or other property in a name other than that of, the registered holder of the Right Certificates evidencing Rights surrendered for exercise or to
issue or deliver any certificates for securities or other property in a name other than that of the registered holder upon the exercise of any Rights until such tax shall have been paid (any such tax
being payable by the holder of such Right Certificate at the time of surrender) or until it has been established to the Company's satisfaction that no such tax is due. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;10.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Preferred Stock Record Date.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Each Person in whose name any certificate for Preferred Stock or
other securities (including any fraction of a share of Preferred Stock or such other securities) is issued upon the exercise of Rights shall for all purposes be deemed to have become the holder of
record of the shares of Preferred Stock or such other securities represented thereby on, and such certificate shall be dated, the date upon which the Right Certificate evidencing such Rights was duly
surrendered and payment of the Exercise Price (and any applicable transfer taxes) was made; </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that if the date of such surrender and
payment is a date upon which the transfer books of the Company for the Preferred Stock or such other securities, as applicable, are closed, such person shall be deemed to have become the record holder
of such shares of Preferred Stock or such other securities on, and such certificate shall be dated, the next succeeding Business Day on which the transfer books of the Company are open; and further </FONT> <FONT SIZE=2><I>provided, however,
</I></FONT><FONT SIZE=2> that if delivery of shares of Preferred Stock or such other securities is delayed pursuant to Section&nbsp;9(c), such Person shall
be deemed to have become the record holder of such shares of Preferred Stock or such other securities only when such shares or such other securities first become deliverable. Prior to the exercise of
the Right evidenced thereby, the holder of a Right Certificate shall not be entitled to any rights of a shareholder of the Company with respect to shares for which the Rights shall be exercisable,
including, without limitation, the right to vote, to receive dividends or other distributions or to exercise any preemptive rights, and shall not be entitled to receive any notice of any proceedings
of the Company, except as provided herein. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;11.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Adjustment of Exercise Price, Number and Kind of Shares or Number of Rights.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The Exercise
Price, the number and kind of shares covered by each Right and the number of Rights outstanding are subject to adjustment from time to time as provided in this Section&nbsp;11. </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;&nbsp;&nbsp;In
the event the Company shall at any time after the date of this Agreement (A)&nbsp;declare a dividend on the Preferred Stock payable in shares of
Preferred Stock, (B)&nbsp;subdivide the outstanding Preferred Stock, (C)&nbsp;combine the outstanding Preferred Stock into a smaller number of shares or (D)&nbsp;issue, change or alter any
shares of its capital stock in a reclassification or recapitalization of the Preferred Stock (including any such reclassification or recapitalization in connection with a consolidation or merger in
which the Company is the continuing or surviving Person), except as otherwise provided in this Section&nbsp;11(a) and Section&nbsp;7(e) hereof, the Exercise Price in effect at the time of the
record date for such dividend or the effective time of such subdivision, combination, reclassification or recapitalization, and the number and kind of shares of capital stock issuable on such date or
at such time, shall be proportionately adjusted so that the holder of any Right exercised after such time shall be entitled to receive the aggregate number and kind of shares of capital stock which,
if such Right had been exercised immediately prior to such date and at a time when the Preferred Stock transfer books of the Company were open, such </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>13</FONT></P>

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<!-- ZEQ.=5,SEQ=16,EFW="2146122",CP="AVANT IMMUNOTHERAPEUTICS,INC.",DN="3",CHK=222898,FOLIO='13',FILE='DISK006:[04BOS0.04BOS2260]KJ2260A.;10',USER='TMCKINN',CD=';8-NOV-2004;13:13' -->
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<P><FONT SIZE=2>holder
would have owned upon such exercise and been entitled to receive by virtue of such dividend, subdivision, combination, reclassification or recapitalization; </FONT><FONT SIZE=2><I>provided,
however,</I></FONT><FONT SIZE=2> that in no event shall the consideration to be paid upon the exercise of a Right be less than the aggregate par value of the shares of capital stock of the Company
issuable upon exercise of a Right. If an event occurs which would require an adjustment under both Section&nbsp;11(a)(i)&nbsp;and Section&nbsp;11(a)(ii)&nbsp;hereof, the adjustment provided
for in this Section&nbsp;11(a)(i)&nbsp;shall be in addition to, and shall be made prior to, any adjustment required pursuant to Section&nbsp;11(a)(ii)&nbsp;hereof. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Subject
to the provisions of Section&nbsp;24 hereof, in the event any Person, alone or together with its Affiliates and Associates, shall
become an Acquiring Person, then, promptly following any such occurrence (a "Section&nbsp;11(a)(ii)&nbsp;Event"), proper provision shall be made so that each holder of a Right, except as provided
in Section&nbsp;7(e) hereof, shall thereafter have a right to receive, upon exercise thereof at the then current Exercise Price in accordance with the terms of this Agreement, in lieu of a number of
one ten-thousandths of a share of Preferred Stock, such number of shares of Common Stock of the Company as shall equal the result obtained by (x)&nbsp;multiplying the then current
Exercise Price by the then number of one ten-thousandths of a share of Preferred Stock for which a Right was exercisable immediately prior to the first occurrence of a
Section&nbsp;11(a)(ii)&nbsp;Event, whether or not such Right was then exercisable, and dividing that product by (y)&nbsp;50% of the Fair Market Value per share of Common Stock of the Company
(determined pursuant to Section&nbsp;11(d)) on the date of the occurrence of a Section&nbsp;11(a)(ii)&nbsp;Event (such number of shares being referred to as the "Adjustment Shares"). </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii)&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;In
lieu of issuing any shares of Common Stock of the Company in accordance with Section&nbsp;11(a)(ii)&nbsp;hereof, the Company, acting
by or pursuant to a resolution of the Board of Directors of the Company, may, and in the event that the number of shares of Common Stock of the Company which are authorized by the Company's
Certificate of Incorporation but not outstanding or reserved for issuance for purposes other than upon exercise of the Rights is not sufficient to permit the exercise in full of the Rights in
accordance with the foregoing subparagraph (ii)&nbsp;of this Section&nbsp;11(a), the Company, acting by or pursuant to a resolution of the Board of Directors of the Company, shall:
(A)&nbsp;determine the excess of (X)&nbsp;the Fair Market Value of the Adjustment Shares issuable upon the exercise of a Right (the "Current Value") over (Y)&nbsp;the Exercise Price attributable
to each Right (such excess being referred to as the "Spread") and (B)&nbsp;with respect to all or a portion of each Right (subject to Section&nbsp;7(e) hereof), make adequate provision to
substitute for the Adjustment Shares, upon payment of the applicable Exercise Price, (1)&nbsp;Common Stock of the Company or equity securities, if any, of the Company other than Common Stock of the
Company (including without limitation shares, or units of shares, of Preferred Stock that the Board of Directors of the Company has determined to have the same value as shares of Common Stock of the
Company (such shares of Preferred Stock being referred to herein as "Common Stock Equivalents")), (2)&nbsp;cash, (3)&nbsp;a reduction in the Exercise Price, (4)&nbsp;Preferred Stock Equivalents
which the Board of Directors of the Company has deemed to have the same value as shares of Common Stock of the Company, (5)&nbsp;debt securities of the Company, (6)&nbsp;other assets or securities
of the Company or (7)&nbsp;any combination of the foregoing, having an aggregate value equal to the Current Value, where such aggregate value has been determined by the Board of Directors of the
Company after receiving the advice of a nationally recognized investment banking firm selected by the Board of Directors of the Company; </FONT><FONT SIZE=2><I>provided,
however,</I></FONT><FONT SIZE=2> that if the Company shall not have made adequate provision to deliver value pursuant to clause&nbsp;(B) above within thirty (30)&nbsp;days following the later of
(x)&nbsp;the first occurrence of a Section&nbsp;11(a)(ii)&nbsp;Event and (y)&nbsp;the date on which the Company's right of redemption pursuant to Section&nbsp;23(a) expires (the later of
(x)&nbsp;and (y)&nbsp;being referred to herein as the "Section&nbsp;11(a)(ii)&nbsp;Trigger Date"), then the Company shall be obligated to deliver, upon the surrender for exercise of a Right
and without requiring payment of the Exercise Price, shares of Common Stock of the Company (to the extent available) and then, if necessary, cash, which shares </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>14</FONT></P>

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<!-- ZEQ.=6,SEQ=17,EFW="2146122",CP="AVANT IMMUNOTHERAPEUTICS,INC.",DN="3",CHK=217523,FOLIO='14',FILE='DISK006:[04BOS0.04BOS2260]KJ2260A.;10',USER='TMCKINN',CD=';8-NOV-2004;13:13' -->
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<UL>
<BR>

<P><FONT SIZE=2>and/or
cash have an aggregate value equal to the Spread. If the Board of Directors of the Company shall determine in good faith that it is likely that sufficient additional shares of Common Stock of
the Company could be authorized for issuance upon exercise in full of the Rights, the 30-day period set forth above may be extended to the extent necessary, but not more than ninety
(90)&nbsp;days after the Section&nbsp;11(a)(ii)&nbsp;Trigger Date, in order that the Company may seek shareholder approval for the authorization of such additional shares (such period, as it may
be extended, being referred to herein as the "Substitution Period"). To the extent that the Company determines that some action need be taken pursuant to the first and/or second sentences of this
Section&nbsp;11(a)(iii), the Company (x)&nbsp;shall provide, subject to Section&nbsp;7(e) hereof, that such action shall apply uniformly to all outstanding Rights and (y)&nbsp;may suspend the
exercisability of the Rights until the expiration of the Substitution Period in order to seek any authorization of additional shares and/or to decide the appropriate form of distribution to be made
pursuant to such first sentence and to determine the value thereof. In the event of any such suspension, the Company shall issue a public announcement stating that the exercisability of the Rights has
been temporarily suspended and a public announcement at such time as the suspension is no longer in effect. For purposes of this Section&nbsp;11(a)(iii), the value of the Common Stock of the Company
and of the Preferred Stock shall be the Fair Market Value (as determined pursuant to Section&nbsp;11(d) hereof) per share of the Common Stock of the Company and the Preferred Stock, respectively, on
the Section&nbsp;11(a)(ii)&nbsp;Trigger Date, the value of any Common Stock Equivalent shall be deemed to have the same value as the Common Stock of the Company on such date and the value of any
Preferred Stock Equivalent shall be deemed to have the same value as the Preferred Stock on such date. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;If
the Company shall fix a record date for the issuance of rights, options or warrants to all holders of Preferred Stock entitling them (for a period expiring within
forty-five (45)&nbsp;calendar days after such record date) to subscribe for or purchase Preferred Stock (or securities having the same or more favorable rights, privileges and
preferences as the shares of Preferred Stock ("Preferred Stock Equivalents")) or securities convertible into Preferred Stock or Preferred Stock Equivalents at a price per share of Preferred Stock or
per share of Preferred Stock Equivalents (or having a conversion price per share, if a security convertible into Preferred Stock or Preferred Stock Equivalents) less than the Fair Market Value (as
determined pursuant to Section&nbsp;11(d) hereof) per share of Preferred Stock on such record date, the Exercise Price to be in effect after such record date shall be determined by multiplying the
Exercise Price in effect immediately prior to such record date by a fraction, the numerator of which shall be the number of shares of Preferred Stock outstanding on such record date, plus the number
of shares of Preferred Stock which the aggregate offering price of the total number of shares of Preferred Stock and/or Preferred Stock Equivalents to be offered (and the aggregate initial conversion
price of the convertible securities so to be offered) would purchase at such Fair Market Value and the denominator of which shall be the number of shares of Preferred Stock outstanding on such record
date, plus the number of additional shares of Preferred Stock and Preferred Stock Equivalents to be offered for subscription or purchase (or into which the convertible securities so to be offered are
initially convertible); </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that in no event shall the consideration to be paid upon the exercise of a Right be less than the aggregate
par value of the shares of stock of the Company issuable upon exercise of a Right. In case such subscription price may be paid in a consideration part or all of which shall be in a form other than
cash, the value of such consideration shall be the Fair Market Value thereof determined in accordance with Section&nbsp;11(d) hereof. Shares of Preferred Stock owned by or held for the account of
the Company shall not be deemed outstanding for the purpose of any such computation. Such adjustments shall be made successively whenever such a record date is fixed; and in the event that such rights
or warrants are not so issued, the Exercise Price shall be adjusted to be the Exercise Price which would then be in effect if such record date had not been fixed. </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>15</FONT></P>

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<!-- ZEQ.=7,SEQ=18,EFW="2146122",CP="AVANT IMMUNOTHERAPEUTICS,INC.",DN="3",CHK=72534,FOLIO='15',FILE='DISK006:[04BOS0.04BOS2260]KJ2260A.;10',USER='TMCKINN',CD=';8-NOV-2004;13:13' -->
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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;&nbsp;If
the Company shall fix a record date for the making of a distribution to all holders of Preferred Stock (including any such distribution made in connection with a
consolidation or merger in which the Company is the continuing or surviving corporation), of evidences of indebtedness, cash (other than a regular periodic cash dividend out of the earnings or
retained earnings of the Company), assets (other than a dividend payable in Preferred Stock, but including any dividend payable in stock other than Preferred Stock) or convertible securities,
subscription rights or warrants (excluding those referred to in Section&nbsp;11(b)), the Exercise Price to be in effect after such record date shall be determined by multiplying the Exercise Price
in effect immediately prior to such record date by a fraction, the numerator of which shall be the Fair Market Value (as determined pursuant to Section&nbsp;11(d) hereof) per one
ten-thousandth of a share of Preferred Stock on such record date, less the Fair Market Value (as determined pursuant to Section&nbsp;11(d) hereof) of the portion of the cash, assets or
evidences of indebtedness so to be distributed or of such convertible securities, subscription rights or warrants applicable to one ten-thousandth of a share of Preferred Stock and the
denominator of which shall be the Fair Market Value (as determined pursuant to Section&nbsp;11(d) hereof) per one ten-thousandth of a share of Preferred Stock; </FONT> <FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that in no event shall
the consideration to be paid upon the exercise of a Right be less than the aggregate par value of the shares
of stock of the Company issuable upon exercise of a Right. Such adjustments shall be made
successively whenever such a record date is fixed; and in the event that such distribution is not so made, the Exercise Price shall again be adjusted to be the Exercise Price which would be in effect
if such record date had not been fixed. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d)&nbsp;&nbsp;&nbsp;For
the purpose of this Agreement, the "Fair Market Value" of any share of Preferred Stock, Common Stock or any other stock or any Right or other security or any other
property shall be determined as provided in this Section&nbsp;11(d). </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;In
the case of a publicly-traded stock or other security, the Fair Market Value on any date shall be deemed to be the average of the daily closing prices per share of
such stock or per unit of such other security for the 30 consecutive Trading Days (as such term is hereinafter defined) immediately prior to such date; </FONT><FONT SIZE=2><I>provided,
however,</I></FONT><FONT SIZE=2> that in the event that the Fair Market Value per share of any share of stock is determined during a period following the announcement by the issuer of such stock of
(x)&nbsp;a dividend or distribution on such stock payable in shares of such stock or securities convertible into shares of such stock or (y)&nbsp;any subdivision, combination or reclassification
of such stock, and prior to the expiration of the 30 Trading Day period after the ex-dividend date for such dividend or distribution, or the record date for such subdivision, combination
or reclassification, then, and in each such case, the Fair Market Value shall be properly adjusted to take into account ex-dividend trading. The closing price for each day shall be the
last sale price, regular way, or, in case no such sale takes place on such day, the average of the closing bid and asked prices, regular way, in either case as reported in the principal consolidated
transaction reporting system with respect to securities listed or admitted to trading on the New York Stock Exchange or, if the securities are not listed or admitted to trading on the New York Stock
Exchange, as reported in the principal consolidated transaction reporting system with respect to securities listed on the principal national securities exchange on which such security is listed or
admitted to trading; or, if not listed or admitted to trading on any national securities exchange, the last quoted price (or, if not so quoted, the average of the last quoted high bid and low asked
prices) in the over-the-counter market, as reported by NASDAQ or such other system then in use; or, if on any such date no bids for such security are quoted by any such
organization, the average of the closing bid and asked prices as furnished by a professional market maker making a market in such security selected by the Board of Directors of the Company. If on any
such date no market maker is making a market in such security, the Fair Market Value of such security on such date shall be determined reasonably and with utmost good faith to the holders of the
Rights by the Board of Directors of the Company, </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that if at the time of </FONT></P>

</UL>
</UL>
<P ALIGN="CENTER"><FONT SIZE=2>16</FONT></P>

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<!-- ZEQ.=8,SEQ=19,EFW="2146122",CP="AVANT IMMUNOTHERAPEUTICS,INC.",DN="3",CHK=197524,FOLIO='16',FILE='DISK006:[04BOS0.04BOS2260]KJ2260A.;10',USER='TMCKINN',CD=';8-NOV-2004;13:13' -->
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<UL>

<P><FONT SIZE=2>such
determination there is an Acquiring Person, the Fair Market Value of such security on such date shall be determined by a nationally recognized investment banking firm selected by the Board of
Directors of the Company, which determination shall be described in a statement filed with the Rights Agent and shall be binding on the Rights Agent and the holders of the Rights. The term "Trading
Day" shall mean a day on which the principal national securities exchange on which such security is listed or admitted to trading is open for the transaction of business or, if such security is not
listed or admitted to trading on any national securities exchange, a Business Day. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;If
a security is not publicly held or not so listed or traded, "Fair Market Value" shall mean the fair value per share of stock or per other unit of such security,
determined reasonably and in good faith to the holders of the Rights by the Board of Directors of the Company; </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that if at the time of
such determination there is an Acquiring Person, the Fair Market Value of such security on such date shall be determined by a nationally recognized investment banking firm selected by the Board of
Directors of the Company, which determination shall be described in a statement filed with the Rights Agent and shall be binding on the Rights Agent and the holders of the Rights; </FONT> <FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2>
that for the purposes of making any adjustment provided for by Section&nbsp;11(a)(ii) hereof, the Fair Market Value of a share of
Preferred Stock shall not be less than the product of the then Fair Market Value of a share of Common Stock multiplied by the higher of the then Dividend Multiple or Vote Multiple (as both of such
terms are defined in the Certificate of Designations attached as Exhibit&nbsp;A hereto) applicable to the Preferred Stock and shall not exceed 105% of the product of the then Fair Market Value of a
share of Common Stock multiplied by the higher of the then Dividend Multiple or Vote Multiple applicable to the Preferred Stock. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii)&nbsp;&nbsp;In
the case of property other than securities, the Fair Market Value thereof shall be determined reasonably and in good faith to the holders of Rights by the Board of
Directors of the Company; </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that if at the time of such determination there is an Acquiring Person, the Fair Market Value of such
property on such date shall be determined by a nationally recognized investment banking firm selected by the Board of Directors of the Company, which determination shall be described in a statement
filed with the Rights Agent and shall be binding upon the Rights Agent and the holders of the Rights. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(e)&nbsp;&nbsp;&nbsp;Anything
herein to the contrary notwithstanding, no adjustment in the Exercise Price shall be required unless such adjustment would require an increase or decrease of at
least 1% in the Exercise Price; </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that any adjustments which by reason of this Section&nbsp;11(e) are not required to be made shall
be carried forward and taken into account in any subsequent adjustment. All calculations under this Section&nbsp;11 shall be made to the nearest cent or to the nearest one-millionth of a
share of Common Stock of the Company or hundred-millionth of a share of Preferred Stock, as the case may be, or to such other figure as the Board of Directors of the Company may deem appropriate.
Notwithstanding the first sentence of this Section&nbsp;11(e), any adjustment required by this Section&nbsp;11 shall be made no later than the earlier of (i)&nbsp;three (3)&nbsp;years from the
date of the transaction which mandates such adjustment or (ii)&nbsp;the Expiration Date. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(f)&nbsp;&nbsp;&nbsp;&nbsp;If
as a result of any provision of Section&nbsp;11(a) or Section&nbsp;13(a) hereof, the holder of any Right thereafter exercised shall become entitled to receive any
shares of capital stock of the Company other than Preferred Stock, thereafter the number of such other shares so receivable upon exercise of any Right shall be subject to adjustment from time to time
in a manner and on terms as nearly equivalent as practicable to the provisions with respect to the Preferred Stock contained in Section&nbsp;11(a), (b), (c), (d), (e), (g)&nbsp;through
(k)&nbsp;and (m), inclusive, and the provisions of Sections 7, 9, 10, 13 and 14 hereof with respect to the Preferred Stock shall apply on like terms to any such other shares. </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>17</FONT></P>

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<BR>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(g)&nbsp;&nbsp;&nbsp;All
Rights originally issued by the Company subsequent to any adjustment made to the Exercise Price hereunder shall evidence the right to purchase, at the adjusted
Exercise Price, the number of one ten-thousandths of a share of Preferred Stock (or other securities or amount of cash or combination thereof) purchasable from time to time hereunder upon
exercise of the Rights, all subject to further adjustment as provided herein. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(h)&nbsp;&nbsp;&nbsp;Unless
the Company shall have exercised its election as provided in Section&nbsp;11(i), upon each adjustment of the Exercise Price as a result of the calculations made
in Section&nbsp;11(b) and (c), each Right outstanding immediately prior to the making of such adjustment shall thereafter evidence the right to purchase, at the adjusted Exercise Price, that number
of one ten-thousandths of a share of Preferred Stock (calculated to the nearest hundred-millionth) as the Board of Directors of the Company determines is appropriate to preserve the
economic value of the Rights, including, by way of example, that number obtained by (i)&nbsp;multiplying (x)&nbsp;the number of one ten-thousandths of a share of Preferred Stock for
which a Right may be exercisable immediately prior to this adjustment by (y)&nbsp;the Exercise Price in effect immediately prior to such adjustment of the Exercise Price and (ii)&nbsp;dividing the
product so obtained by the Exercise Price in effect immediately after such adjustment of the Exercise Price. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;&nbsp;&nbsp;The
Company may elect on or after the date of any adjustment of the Exercise Price to adjust the number of Rights, in substitution for any adjustment in the number of
shares of Preferred Stock purchasable upon the exercise of a Right. Each of the Rights outstanding after the adjustment in the number of Rights shall be exercisable for the number of one
ten-thousandths of a share of Preferred Stock for which a Right was exercisable immediately prior to such adjustment. Each Right held of record prior to such adjustment of the number of
Rights shall become that number of Rights (calculated to the nearest one-millionth) obtained by dividing the Exercise Price in effect immediately prior to adjustment of the Exercise Price
by the Exercise Price in effect immediately after adjustment of the Exercise Price. The Company shall make a public announcement of its election to adjust the number of Rights, indicating the record
date for the adjustment, and, if known at the time, the amount of the adjustment to be made. This record date may be the date on which the Exercise Price is adjusted or any day thereafter, but, if the
Right Certificates have been issued, shall be at least ten (10)&nbsp;days later than the date of the public announcement. If Right Certificates have been issued, upon each adjustment of the number
of Rights pursuant to this Section&nbsp;11(i), the Company shall, as promptly as practicable, cause to be distributed to holders of record of Right Certificates on such record date Right
Certificates evidencing, subject to Section&nbsp;14 hereof, the additional Rights to which such holders shall be entitled as a result of such adjustment, or, at the option of the Company, shall
cause to be distributed to such holders of record in substitution and replacement for the Right Certificates held by such holders prior to the date of adjustment, and upon surrender thereof, if
required by the Company, new Right Certificates evidencing all the Rights to which such holders shall be entitled after such adjustment. Right Certificates so to be distributed shall be issued,
executed and countersigned in the manner provided for herein (and may bear, at the option of the Company, the adjusted Exercise Price) and shall be registered in the names of the holders of record of
Right Certificates on the record date specified in the public announcement. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(j)&nbsp;&nbsp;&nbsp;&nbsp;Irrespective
of any adjustment or change in the Exercise Price or the number of one ten-thousandths of a share of Preferred Stock issuable upon the exercise
of the Rights, the Right Certificates theretofore and thereafter issued may continue to express the Exercise Price per
share and the number of shares which were expressed in the initial Right Certificates issued hereunder without prejudice to any adjustment or change. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(k)&nbsp;&nbsp;&nbsp;Before
taking any action that would cause an adjustment reducing the Exercise Price below the then stated value, if any, of the number of one ten-thousandths
of a share of Preferred Stock issuable upon exercise of the Rights, the Company shall take any corporate action which </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>18</FONT></P>

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<BR>

<P><FONT SIZE=2>may,
in the opinion of its counsel, be necessary in order that the Company may validly and legally issue fully paid and nonassessable shares of Preferred Stock at such adjusted Exercise Price. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(l)&nbsp;&nbsp;&nbsp;&nbsp;In
any case in which this Section&nbsp;11 shall require that an adjustment in the Exercise Price be made effective as of a record date for a specified event, the
Company may elect to defer until the occurrence of such event the issuing to the holder of any Right exercised after such record date the number of one ten-thousandths of a share of
Preferred Stock or other capital stock or securities of the Company, if any, issuable upon such exercise over and above the number of one ten-thousandths of a share of Preferred Stock and
other capital stock or securities of the Company, if any, issuable upon such exercise on the basis of the Exercise Price in effect prior to such adjustment; </FONT><FONT SIZE=2><I>provided,
however,</I></FONT><FONT SIZE=2> that the Company shall deliver to such holder a due bill or other appropriate instrument evidencing such holder's right to receive such additional shares upon the
occurrence of the event requiring such adjustment. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(m)&nbsp;&nbsp;Anything
in this Section&nbsp;11 to the contrary notwithstanding, the Company shall be entitled to make such reductions in the Exercise Price, in addition to those
adjustments expressly required by this Section&nbsp;11, as and to the extent that in its good faith judgment the Board of Directors of the Company shall determine to be advisable in order that any
consolidation or subdivision of the Preferred Stock, issuance wholly for cash of any shares of Preferred Stock at less than the Fair Market Value, issuance wholly for cash of shares of Preferred Stock
or securities which by their terms are convertible into or exchangeable for shares of Preferred Stock, stock dividends or issuance of rights, options or warrants referred to hereinabove in this
Section&nbsp;11, hereafter made by the Company to holders of its Preferred Stock, shall not be taxable to such shareholders. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(n)&nbsp;&nbsp;&nbsp;The
Company covenants and agrees that it shall not, at any time after the Distribution Date and so long as the Rights have not been redeemed pursuant to
Section&nbsp;23 hereof or exchanged pursuant to Section&nbsp;24 hereof, (i)&nbsp;consolidate with (other than a Subsidiary of the Company in a transaction that complies with the proviso at the
end of this sentence), (ii)&nbsp;merge with or into, or (iii)&nbsp;sell or transfer (or permit any Subsidiary to sell or transfer), in one transaction or a series of related transactions, assets
or earning power aggregating 50% or more of the assets or earning power of the Company and its Subsidiaries taken as a whole, to any other Person or Persons (other than the Company and/or any of its
Subsidiaries in one or more transactions each of which complies with the proviso at the end of this sentence) if (x)&nbsp;at the time of or immediately after such consolidation, merger or sale there
are any rights, warrants or other instruments outstanding or agreements or arrangements in effect which would substantially diminish or otherwise eliminate the benefits intended to be afforded by the
Rights, or
(y)&nbsp;prior to, simultaneously with or immediately after such consolidation, merger or sale the shareholders of a Person who constitutes, or would constitute, the "Principal Party" for the
purposes of Section&nbsp;13(a) hereof shall have received a distribution of Rights previously owned by such Person or any of its Affiliates and Associates; </FONT><FONT SIZE=2><I>provided,
however,</I></FONT><FONT SIZE=2> that, subject to the following sentence, this Section&nbsp;11(n) shall not affect the ability of any Subsidiary of the Company to consolidate with, or merge with or
into, or sell or transfer assets or earning power to, any other Subsidiary of the Company. The Company further covenants and agrees that after the Distribution Date it will not, except as permitted by
Section&nbsp;23 or Section&nbsp;27 hereof, take (or permit any Subsidiary to take) any action if at the time such action is taken it is reasonably foreseeable that such action will substantially
diminish or otherwise eliminate the benefits intended to be afforded by the Rights. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(o)&nbsp;&nbsp;&nbsp;Notwithstanding
anything in this Agreement to the contrary, in the event the Company shall at any time after the date of this Agreement and prior to the Distribution
Date (i)&nbsp;declare or pay any dividend on the outstanding Common Stock of the Company payable in shares of Common Stock of the Company or (ii)&nbsp;effect a subdivision, combination or
consolidation of the outstanding shares of Common Stock of the Company (by reclassification or otherwise than by </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>19</FONT></P>

<HR NOSHADE>
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<A NAME="page_kj2260_1_20"> </A>
<UL>
<BR>

<P><FONT SIZE=2>payment
of dividends in shares of Common Stock of the Company) into a greater or lesser number of shares of Common Stock of the Company, then in any such case (A)&nbsp;the number of one
ten-thousandths of a share of Preferred Stock purchasable after such event upon proper exercise of each Right shall be determined by multiplying the number of one
ten-thousandths of a share of Preferred Stock so purchasable immediately prior to such event by a fraction, the numerator of which is the number of shares of Common Stock of the Company
outstanding immediately prior to such event and the denominator of which is the number of shares of Common Stock of the Company outstanding immediately after such event, and (B)&nbsp;each share of
Common Stock of the Company outstanding immediately after such event shall have issued with respect to it that number of Rights which each share of Common Stock of the Company outstanding immediately
prior to such event had issued with respect to it. The adjustments provided for in this Section&nbsp;11(o) shall be made successively whenever such a dividend is declared or paid or such a
subdivision, combination or consolidation is effected. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(p)&nbsp;&nbsp;&nbsp;The
exercise of Rights under Section&nbsp;11(a)(ii)&nbsp;shall only result in the loss of rights under Section&nbsp;11(a)(ii)&nbsp;to the extent so exercised and
neither such exercise nor any exchange of Rights pursuant to Section&nbsp;24 shall otherwise affect the rights of holders of Right Certificates under this Rights Agreement, including rights to
purchase securities of the Principal Party following a Section&nbsp;13 Event which has occurred or may thereafter occur, as set forth in Section&nbsp;13 hereof. Upon exercise of a Right
Certificate under Section&nbsp;11(a)(ii), the Rights Agent shall return such Right Certificate duly marked to indicate that such exercise has occurred. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;12.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Certificate of Adjusted Exercise Price or Number of Shares.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Whenever an adjustment is made as
provided in Section&nbsp;11 or Section&nbsp;13 hereof, the Company shall (a)&nbsp;promptly prepare a certificate setting forth such adjustment and a brief statement of the facts accounting for
such adjustment, (b)&nbsp;promptly file with the Rights Agent and with each transfer agent for the Preferred Stock and the Common Stock of the Company a copy of such certificate and (c)&nbsp;mail
a brief summary thereof to each holder of a
Right Certificate (or, if prior to the Distribution Date, to each holder of a certificate representing shares of Common Stock of the Company) in accordance with Section&nbsp;26 hereof. The Rights
Agent shall be fully protected in relying on any such certificate and on any adjustment contained therein and shall not be deemed to have knowledge of any such adjustment unless and until it shall
have received such certificate. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>20</FONT></P>

<HR NOSHADE>
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<P><FONT SIZE=2><A
NAME="page_kk2260_1_21"> </A> </FONT> <FONT SIZE=2>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;13.</FONT><FONT SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Consolidation, Merger or Sale or Transfer of Assets or Earning Power.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;In
the event that, following the Stock Acquisition Date, directly or indirectly, (x)&nbsp;the Company shall consolidate with, or merge with and into, any other Person
(other than a Subsidiary of the Company in a transaction which is not prohibited by Section&nbsp;11(n) hereof), and the Company shall not be the continuing or surviving corporation of such
consolidation or merger, (y)&nbsp;any Person (other than a Subsidiary of the Company in a transaction which is not prohibited by the proviso at the end of the first sentence of Section&nbsp;11(n)
hereof) shall consolidate with the Company, or merge with and into the Company and the Company shall be the continuing or surviving corporation of such merger and, in connection with such merger, all
or part of the shares of Common Stock of the Company shall be changed into or exchanged for stock or other securities of any other Person or cash or any other property, or (z)&nbsp;the Company shall
sell, mortgage or otherwise transfer (or one or more of its Subsidiaries shall sell, mortgage or otherwise transfer), in one transaction or a series of related transactions, assets or earning power
aggregating 50% or more of the assets or earning power of the Company and its Subsidiaries (taken as a whole) to any other Person or Persons (other than the Company or any Subsidiary of the Company in
one or more transactions, each of which is not prohibited by the proviso at the end of the first sentence of Section&nbsp;11(n) hereof), then, and in each such case, proper provision shall be made
so that: (i)&nbsp;each holder of a Right, except as provided in Section&nbsp;7(e) hereof, shall have the right to receive, upon the exercise thereof at the then current Exercise Price in
accordance with the terms of this Agreement, such number of validly authorized and issued, fully paid and nonassessable shares of freely tradable Common Stock of the Principal Party (as hereinafter
defined in Section&nbsp;13(b)), free and clear of rights of call or first refusal, liens, encumbrances, transfer restrictions or other adverse claims, as shall be equal to the result obtained by
(1)&nbsp;multiplying the then current Exercise Price by the number of one ten-thousandths of a share of Preferred Stock for which a Right is exercisable immediately prior to the first
occurrence of a Section&nbsp;13 Event (without taking into account any adjustment previously made pursuant to Section&nbsp;11(a)(ii)&nbsp;or 11(a)(iii)&nbsp;hereof), and dividing that product
by (2)&nbsp;50% of the Fair Market Value (determined pursuant to Section&nbsp;11(d) hereof) per share of the Common Stock of such Principal Party on the date of consummation of such consolidation,
merger, sale or transfer; (ii)&nbsp;such Principal Party shall thereafter be liable for, and shall assume, by virtue of such consolidation, merger, sale, mortgage or transfer, all the obligations
and duties of the Company pursuant to this Agreement; (iii)&nbsp;the term "Company" shall thereafter be deemed to refer to such Principal Party, it being specifically intended that the provisions of
Section&nbsp;11 hereof shall apply to such Principal Party; and (iv)&nbsp;such Principal Party shall take such steps (including, but not limited to, the reservation of a sufficient number of
shares of its Common Stock to permit exercise of all outstanding Rights in accordance with this Section&nbsp;13(a) and the making of payments in cash and/or other securities in accordance with
Section&nbsp;11(a)(iii)&nbsp;hereof) in connection with such consummation as may be necessary to assure that the provisions hereof shall thereafter be applicable, as nearly as reasonably may be,
in relation to its shares of Common Stock thereafter deliverable upon the exercise of the Rights. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;"Principal
Party" shall mean: </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;in
the case of any transaction described in clause&nbsp;(x) or (y)&nbsp;of the first sentence of Section&nbsp;13(a), the Person that is the issuer of any
securities into which shares of Common Stock of the Company are converted in such merger or consolidation, or, if there is more than one such issuer, the issuer of Common Stock that has the highest
aggregate Fair Market Value (determined pursuant to Section&nbsp;11(d)), and if no securities are so issued, the Person that is the other party to the merger or consolidation, or, if there is more
than one such Person, the Person the Common Stock of which has the highest aggregate Fair Market Value (determined pursuant to Section&nbsp;11(d)); and </FONT></P>

</UL>
</UL>
<P ALIGN="CENTER"><FONT SIZE=2>21</FONT></P>

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<A NAME="page_kk2260_1_22"> </A>
<UL>
<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;in
the case of any transaction described in clause&nbsp;(z) of the first sentence of Section&nbsp;13(a), the Person that is the party receiving the greatest portion
of the assets or earning power transferred pursuant to such transaction or transactions, or, if each Person that is a party to such transaction or transactions receives the same portion of the assets
or earning power transferred pursuant to such transaction or transactions or if the Person receiving the largest portion of the assets or earning power cannot be determined, whichever Person the
Common Stock of which has the highest aggregate Fair Market Value (determined pursuant to Section&nbsp;11(d)); </FONT></P>

</UL>
</UL>

<P><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that in any such case described in clauses (i)&nbsp;or (ii)&nbsp;of Section&nbsp;13(b) hereof, (1)&nbsp;if the Common Stock
of such Person is not at such time and has not been continuously over the preceding 12-month period registered under Section&nbsp;12 of the Exchange Act ("Registered Common Stock") or
such Person is not a corporation, and such Person is a direct or indirect Subsidiary or Affiliate of another Person who has Registered Common Stock outstanding, "Principal Party" shall refer to such
other Person; (2)&nbsp;if the Common Stock of such Person is not Registered Common Stock or such Person is not a corporation, and such Person is a direct or indirect Subsidiary of another Person but
is not a direct or indirect Subsidiary of another Person which has Registered Common Stock outstanding, "Principal Party" shall refer to the ultimate parent entity of such first-mentioned Person;
(3)&nbsp;if the Common Stock of such Person is not Registered Common Stock or such Person is not a corporation, and such Person is directly or indirectly controlled by more than one Person, and one
or more of such other Persons has Registered Common Stock outstanding, "Principal Party" shall refer to whichever of such other Persons is the issuer of the Registered Common Stock having the highest
aggregate Fair Market Value (determined pursuant to Section&nbsp;11(d)); and (4)&nbsp;if the Common Stock of such Person is not Registered Common Stock or such Person is not a corporation, and
such Person is directly or indirectly controlled by more than one Person, and none of such other Persons has Registered Common Stock outstanding, "Principal Party" shall refer to whichever ultimate
parent entity is the corporation having the greatest shareholders' equity or, if no such ultimate parent entity is a corporation, "Principal Party" shall refer to whichever ultimate parent entity is
the entity having the greatest net assets. </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;&nbsp;The
Company shall not consummate any such consolidation, merger, sale or transfer unless prior thereto (x)&nbsp;the Principal Party shall have a sufficient number of
authorized shares of its Common Stock, which have not been issued or reserved for issuance, to permit the exercise in full of the Rights in accordance with this Section&nbsp;13, and (y)&nbsp;the
Company and each Principal Party and each other Person who may become a Principal Party as a result of such consolidation, merger, sale or transfer shall have
executed and delivered to the Rights Agent a supplemental agreement providing for the terms set forth in Section&nbsp;13(a) and (b)&nbsp;and further providing that, as soon as practicable after
the date of any consolidation, merger, sale or transfer of assets mentioned in Section&nbsp;13(a), the Principal Party at its own expense will: </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;prepare
and file&nbsp;a registration statement under the Securities Act with respect to the Rights and the securities purchasable upon exercise of the Rights on an
appropriate form, cause such registration statement to become effective as soon as practicable after such filing and cause such registration statement to remain effective (with a prospectus that at
all times meets the requirements of the Securities Act) until the Expiration Date; </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;qualify
or register the Rights and the securities purchasable upon exercise of the Rights under the blue sky laws of such jurisdictions as may be necessary or
appropriate; </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii)&nbsp;&nbsp;list
(or continue the listing of) the Rights and the securities purchasable upon exercise of the Rights on a national securities exchange or to meet the eligibility
requirements for quotation on NASDAQ; and </FONT></P>

</UL>
</UL>
<P ALIGN="CENTER"><FONT SIZE=2>22</FONT></P>

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<UL>
<UL>
<BR>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iv)&nbsp;&nbsp;deliver
to holders of the Rights historical financial statements for the Principal Party and each of its Affiliates which comply in all respects with the requirements
for registration on Form&nbsp;10 under the Exchange Act. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d)&nbsp;&nbsp;&nbsp;In
case the Principal Party which is to be a party to a transaction referred to in this Section&nbsp;13 has a provision in any of its authorized securities or in its
certificate of incorporation or By-laws or other instrument governing its affairs, which provision would have the effect of (i)&nbsp;causing such Principal Party to issue (other than to
holders of Rights pursuant to this Section&nbsp;13), in connection with, or as a consequence of, the consummation of a transaction referred to in this Section&nbsp;13, shares of Common Stock of
such Principal Party at less than the then current Fair Market Value (determined pursuant to Section&nbsp;11(d)) or securities exercisable for, or convertible into, Common Stock of such Principal
Party at less than such Fair Market Value, or (ii)&nbsp;providing for any special payment, tax or similar provisions in connection with the issuance of the Common Stock of such Principal Party
pursuant to the provisions of this Section&nbsp;13, then, in such event, the Company shall not consummate any such transaction unless prior thereto the Company and such Principal Party shall have
executed and delivered to the Rights Agent a supplemental agreement providing that the provision in question of such Principal Party shall have been canceled, waived or amended, or that the authorized
securities shall be redeemed, so that the applicable provision will have no effect in connection with, or as a consequence of, the consummation of the proposed transaction. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The
provisions of this Section&nbsp;13 shall similarly apply to successive mergers or consolidations or sales or other transfers. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;14.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Fractional Rights and Fractional Shares.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;The
Company shall not be required to issue fractions of Rights, except prior to the Distribution Date as provided in Section&nbsp;11(o) hereof, or to distribute Right
Certificates which evidence fractional Rights. If the Company elects not to issue such fractional Rights, the Company shall pay, in lieu of such fractional Rights, to the registered holders of the
Right Certificates with regard to which such fractional Rights would otherwise be issuable, an amount in cash equal to the same fraction of the Fair Market Value of a whole Right, as determined
pursuant to Section&nbsp;11(d) hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;The
Company shall not be required to issue fractions of shares of Preferred Stock (other than fractions which are integral multiples of one ten-thousandth of
a share of Preferred Stock) upon exercise of the Rights or to distribute certificates which evidence fractional shares of Preferred Stock (other than fractions which are integral multiples of one
ten-thousandth of a share of Preferred Stock). In lieu of fractional shares of Preferred Stock that are not integral multiples of one ten-thousandth of a share of Preferred
Stock, the Company may pay to the registered holders of Right Certificates at the time such Rights are exercised as herein provided an amount in cash equal to the same fraction of the Fair Market
Value of one ten-thousandth of a share of Preferred Stock. For purposes of this Section&nbsp;14(b), the Fair Market Value of one ten-thousandth of a share of Preferred Stock
shall be determined pursuant to Section&nbsp;11(d) hereof for the Trading Day immediately prior to the date of such exercise. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;&nbsp;The
holder of a Right by the acceptance of the Rights expressly waives his right to receive any fractional Rights or any fractional shares upon exercise of a Right,
except as permitted by this Section&nbsp;14. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;15.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Rights of Action.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;All rights of action in respect of this Agreement, other than rights of
action vested in the Rights Agent pursuant to Sections 18 and 20 hereof, are vested in the respective registered holders of the Right Certificates (or, prior to the Distribution Date, the registered
holders of the Common Stock of the Company); and any registered holder of any Right Certificate (or, prior to </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>23</FONT></P>

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<A NAME="page_kk2260_1_24"> </A>

<P><FONT SIZE=2>the
Distribution Date, of the Common Stock of the Company), without the consent of the Rights Agent or of the holder of any other Right Certificate (or, prior to the Distribution Date, of the Common
Stock of the Company), may, in such registered holder's own behalf and for such registered holder's own benefit, enforce, and may institute and maintain any suit, action or proceeding against the
Company to enforce, or otherwise act in respect of, his right to exercise the Right evidenced by such Right Certificate in the manner provided in such Right Certificate and in this Agreement. Without
limiting the foregoing or any remedies available to the holders of Rights, it is specifically acknowledged that the holders of Rights would not have an adequate remedy at law for any breach of this
Agreement and shall be entitled to specific performance of the obligations hereunder and injunctive relief against actual or threatened violations of the obligations hereunder of any Person subject to
this Agreement. Holders of Rights shall be entitled to recover the reasonable costs and expenses, including attorneys' fees, incurred by them in any action to enforce the provisions of this Agreement. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;16.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Agreement of Right Holders.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Every holder of a Right, by accepting the same, consents and
agrees with the Company and the Rights Agent and with every other holder of a Right that: </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;prior
to the Distribution Date, each Right will be transferable only simultaneously and together with the transfer of shares of Common Stock of the Company; </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;after
the Distribution Date, the Right Certificates are transferable only on the registry books of the Rights Agent if surrendered at the office or offices of the Rights
Agent designated for such purpose, duly endorsed or accompanied by a proper instrument of transfer; </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;&nbsp;subject
to Sections 6(a) and 7(f), the Company and the Rights Agent may deem and treat the person in whose name a Right Certificate (or, prior to the Distribution Date,
the associated certificate representing Common Stock of the Company) is registered as the absolute owner thereof and of the Rights evidenced thereby (notwithstanding any notations of ownership or
writing on the Right Certificates or the associated certificate representing Common Stock of the Company made by anyone other than the Company or the Rights Agent) for all purposes whatsoever, and,
subject to the last sentence of Section&nbsp;7(e), neither the Company nor the Rights Agent shall be affected by any notice to the contrary; and </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d)&nbsp;&nbsp;&nbsp;notwithstanding
anything in this Agreement to the contrary, neither the Company nor the Rights Agent shall have any liability to any holder of a Right or other Person as
the result of its inability to
perform any of its obligations under this Agreement by reason of any preliminary or permanent injunction or other order, decree or ruling issued by a court of competent jurisdiction or by a
governmental, regulatory or administrative agency or commission, or any statute, rule, regulation or executive order promulgated or enacted by any governmental authority prohibiting or otherwise
restraining performance of such obligations; </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that the Company must use its best efforts to have any such order, decree or ruling
lifted or otherwise overturned as soon as possible. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;17.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Right Certificate Holder Not Deemed a Shareholder.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;No holder, as such, of any Right
Certificate shall be entitled to vote, receive dividends or be deemed for any purpose the holder of the shares of Preferred Stock or any other securities of the Company which may at any time be
issuable on the exercise of the Rights represented thereby, nor shall anything contained herein or in any Right Certificate be construed to confer upon the holder of any Right Certificate, as such,
any of the rights of a shareholder of the Company or any right to vote for the election of directors or upon any matter submitted to shareholders at any meeting thereof, or to give or withhold consent
to any corporate action, or to receive notice of meetings or other actions affecting shareholders (except as provided in Section&nbsp;25 hereof), or to receive dividends or subscription rights, or
otherwise, until the Right or Rights evidenced by such Right Certificate shall have been exercised in accordance with the provisions hereof. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>24</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<A NAME="page_kk2260_1_25"> </A>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;18.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Concerning the Rights Agent.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;The
Company agrees to pay to the Rights Agent such compensation as shall be agreed to in writing between the Company and the Rights Agent for all services rendered by it
hereunder and, from time to time, on demand of the Rights Agent, its reasonable expenses and counsel fees and disbursements and other disbursements incurred in the administration and execution of this
Agreement and the exercise and performance of its duties hereunder. The Company also agrees to indemnify the Rights Agent for, and to hold it harmless against, any loss, liability, or expense,
incurred without gross negligence, bad faith or willful misconduct on the part of the Rights Agent, for anything done or omitted by the Rights Agent in connection with the acceptance and
administration of this Agreement, including the costs and expenses of defending against any claim of liability arising therefrom, directly or indirectly. The provisions of this Section&nbsp;18(a)
shall survive the expiration of the Rights and the termination of this Agreement. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;The
Rights Agent shall be protected and shall incur no liability for or in respect of any action taken, suffered or omitted by it in connection with its administration
of this Agreement in reliance upon any Right Certificate or certificate representing Common Stock of the Company, Preferred Stock, or other securities of the Company, instrument of assignment or
transfer, power of attorney, endorsement, affidavit, letter, notice, direction, consent, certificate, statement, or other paper or document believed by it in good faith and without negligence to be
genuine and to be signed and executed by the proper Person or Persons. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;&nbsp;The
Rights Agent shall not be liable for consequential damages under any provision of this Agreement or for any consequential damages arising out of any act or failure
to act hereunder. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;19.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Merger or Consolidation or Change of Name of Rights Agent.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;Any
corporation into which the Rights Agent or any successor Rights Agent may be merged or with which it may be consolidated, or any corporation resulting from any
merger or consolidation to which the Rights Agent or any successor Rights Agent shall be a party, or any corporation succeeding to the corporate trust or shareholder services business of the Rights
Agent or any successor Rights Agent, shall be the successor to the Rights Agent under this Agreement without the execution or filing of any paper or any further act on the part of any of the parties
hereto, provided that such corporation would be eligible for appointment as a successor Rights Agent under the provisions of Section&nbsp;21 hereof. In case at the time such successor Rights Agent
shall succeed to the agency created by this Agreement, any of the Right Certificates shall have been countersigned but not delivered, any such successor Rights Agent may adopt the countersignature of
the predecessor Rights Agent and deliver such Right Certificates so countersigned; and in case at that time any of the Right Certificates shall not have been countersigned, any successor Rights Agent
may countersign such Right Certificates either in the name of the predecessor or in the name of the successor Rights Agent; and in all such cases such Right Certificates shall have the full force
provided in the Right Certificates and in this Agreement. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;In
case at any time the name of the Rights Agent shall be changed and at such time any of the Right Certificates shall have been countersigned but not delivered, the
Rights Agent may adopt the countersignature under its prior name and deliver Right Certificates so countersigned; and in case at that time any of the Right Certificates shall not have been
countersigned, the Rights Agent may countersign such Right Certificates either in its prior name or in its changed name; and in all such cases such Right Certificates shall have the full force
provided in the Right Certificates and in this Agreement. </FONT></P>

</UL>
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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;20.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Duties of Rights Agent.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The Rights Agent undertakes the duties and obligations expressly
imposed by this Agreement upon the following terms and conditions, by all of which the Company and the holders of Right Certificates, by their acceptance thereof, shall be bound: </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;The
Rights Agent may consult with legal counsel selected by it (who may be legal counsel for the Company), and the opinion of such counsel shall be full and complete
authorization and protection to the Rights Agent as to any action taken or omitted by it in good faith and in accordance with such opinion. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;Whenever
in the performance of its duties under this Agreement the Rights Agent shall deem it necessary or desirable that any fact or matter (including, without
limitation, the identity of any Acquiring Person and the determination of "Fair Market Value") be proved or established by the Company prior to taking or suffering any action hereunder, such fact or
matter (unless other evidence in respect thereof shall be herein specifically prescribed) may be deemed to be conclusively proved and established by a certificate signed by a person believed by the
Rights Agent to be the Chairman of the Board of Directors, a Vice Chairman of the Board of Directors, the President, a Vice President, the Treasurer, any Assistant Treasurer, the Secretary or an
Assistant Secretary of the Company and delivered to the Rights Agent. Any such certificate shall be full authorization to the Rights Agent for any action taken or suffered in good faith by it under
the provisions of this Agreement in reliance upon such certificate. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;&nbsp;The
Rights Agent shall be liable hereunder only for its own gross negligence, bad faith or willful misconduct. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d)&nbsp;&nbsp;&nbsp;The
Rights Agent shall not be liable for or by reason of any of the statements of fact or recitals contained in this Agreement or in the Right Certificates (except its
countersignature thereof) or be required to verify the same, but all such statements and recitals are and shall be deemed to have been made by the Company only. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(e)&nbsp;&nbsp;&nbsp;The
Rights Agent shall not be under any responsibility in respect of the validity of this Agreement or the execution and delivery hereof (except the due execution hereof
by the Rights Agent) or in respect of the validity or execution of any Right Certificate (except its countersignature thereof); nor shall it be responsible for any breach by the Company of any
covenant or condition contained in this Agreement or in any Right Certificate; nor shall it be responsible for any change in the exercisability of the Rights (including the Rights becoming void
pursuant to Section&nbsp;7(e) hereof) or any adjustment required under the provisions of Sections 11, 13 or 23(c) hereof or responsible for the manner, method or amount of any such adjustment or the
ascertaining of the existence of facts that would require any such adjustment (except with respect to the exercise of Rights evidenced by Right Certificates after receipt of a certificate describing
any such adjustment furnished in accordance with Section&nbsp;12 hereof), nor shall it be responsible for any determination by the Board of Directors of the Company of the Fair Market Value of the
Rights or Preferred Stock pursuant to the provisions of Section&nbsp;14 hereof; nor shall it by any act hereunder be deemed to make any representation or warranty as to the authorization or
reservation of any shares of Common Stock of the Company or Preferred Stock to be issued pursuant to this Agreement or any Right Certificate or as to whether or not any shares of Common Stock of the
Company or Preferred Stock will, when so issued, be validly authorized and issued, fully paid and nonassessable. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(f)&nbsp;&nbsp;&nbsp;&nbsp;The
Company agrees that it will perform, execute, acknowledge and deliver or cause to be performed, executed, acknowledged and delivered all such further and other acts,
instruments and assurances as may reasonably be required by the Rights Agent for the carrying out or performing by the Rights Agent of the provisions of this Agreement. </FONT></P>

</UL>
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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(g)&nbsp;&nbsp;&nbsp;The
Rights Agent is hereby authorized and directed to accept instructions with respect to the performance of its duties hereunder and certificates delivered pursuant to
any provision hereof from any person believed by the Rights Agent to be the Chairman of the Board of Directors, any Vice Chairman of the Board of Directors, the President, a Vice President, the
Secretary, an Assistant Secretary, the Treasurer or an Assistant Treasurer of the Company, and is authorized to apply to such officers for advice or instructions in connection with its duties, and it
shall not be liable for any action taken or suffered to be taken by it in good faith in accordance with instructions of any such officer. Any application by the Rights Agent for written instructions
from the Company may, at the option of the Rights Agent, set forth in writing any action proposed to be taken or omitted by the Rights Agent under this Agreement and the date on or after which such
action shall be taken or such omission shall be effective. The Rights Agent shall not be liable for any action taken by, or omission of, the Rights Agent in accordance with a proposal included in such
application on or after the date specified in such application (which date shall not be less than five Business Days after the date any officer of the Company actually receives such application,
unless any such officer shall have consented in writing to an earlier date) unless, prior to taking any such action (or the effective date in the case of an omission), the Rights Agent shall have
received written instructions in response to such application specifying the action to be taken or omitted. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(h)&nbsp;&nbsp;&nbsp;The
Rights Agent and any shareholder, director, officer or employee of the Rights Agent may buy, sell or deal in any of the Rights or other securities of the Company or
become pecuniarily interested in any transaction in which the Company may be interested, or contract with or lend money to the Company or otherwise act as fully and freely as though it were not the
Rights Agent under this Agreement. Nothing herein shall preclude the Rights Agent from acting in any other capacity for the Company or for any other legal entity. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;&nbsp;&nbsp;The
Rights Agent may execute and exercise any of the rights or powers hereby vested in it or perform any duty hereunder either itself or by or through its attorneys or
agents. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(j)&nbsp;&nbsp;&nbsp;&nbsp;No
provision of this Agreement shall require the Rights Agent to expend or risk its own funds or otherwise incur any financial liability in the performance of any of its
duties hereunder or in the exercise of its rights if there shall be reasonable grounds for believing that repayment of such funds or adequate indemnification against such risk or liability is not
reasonably assured to it. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(k)&nbsp;&nbsp;&nbsp;If,
with respect to any Right Certificate surrendered to the Rights Agent for exercise or transfer, the certificate attached to the form of assignment or form of
election to purchase, as the case may be, has either not been completed or indicates an affirmative response to clause&nbsp;(1) or clause&nbsp;(2) thereof, the Rights Agent shall not take any
further action with respect to such requested exercise or transfer without first consulting with the Company. </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>27</FONT></P>

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<P><FONT SIZE=2><A
NAME="page_kl2260_1_28"> </A> </FONT> <FONT SIZE=2>
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;21.</FONT><FONT SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Change of Rights Agent.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The Rights Agent or any successor Rights Agent may resign and be
discharged from its duties under this Agreement upon thirty (30)&nbsp;days' notice in writing mailed to the Company by first class mail, </FONT><FONT SIZE=2><I>provided,
however,</I></FONT><FONT SIZE=2> that in the event the transfer agency relationship in effect between the Company and the Rights Agent with respect to the Common Stock of the Company terminates, the
Rights Agent will be deemed to have resigned automatically on the effective date of such termination. The Company may remove the Rights Agent or any successor Rights Agent (with or without cause),
effective immediately or on a specified date, by written notice given to the Rights Agent or successor Rights Agent, as the case may be, and to each transfer agent of the Common Stock of the Company
and Preferred Stock, and by giving notice to the holders of the Right Certificates by any means reasonably determined by the Company to inform such holders of such removal (including without
limitation, by including such information in one or more of the Company's reports to shareholders or reports or filings with the Securities and Exchange Commission). If the Rights Agent shall resign
or be removed or shall otherwise become incapable of acting, the Company shall appoint a successor to the Rights Agent. If the Company shall fail to make such appointment within a period of thirty
(30)&nbsp;days after giving notice of such removal or after it has been notified in writing of such resignation or incapacity by the resigning or incapacitated Rights Agent or by the holder of a
Right Certificate (who shall, with such notice, submit his Right Certificate for inspection by the Company), then the incumbent Rights Agent or the registered holder of any Right Certificate may apply
to any court of competent jurisdiction for the appointment of a new Rights Agent. Any successor Rights Agent, whether appointed by the Company or by such a court, shall be (a)&nbsp;a corporation
organized and doing business under the laws of the United States, the State of Delaware or the State of New York (or of any other state of the United States so long as such corporation is authorized
to do business as a banking institution in the State of Delaware or the State of New York), in good standing, which is authorized under such laws to exercise stock transfer or corporate trust powers
and is subject to supervision or examination by federal or state authority and which has at the time of its appointment as Rights Agent a combined capital and surplus of at least $10,000,000 or
(b)&nbsp;an Affiliate of a Person described in clause&nbsp;(a) of this sentence. After appointment, the successor Rights Agent shall be vested with the same powers, rights, duties and
responsibilities as if it had been originally named as Rights Agent without further act or deed; but the predecessor Rights Agent shall deliver and transfer to the successor Rights Agent any property
at the time held by it hereunder, and execute and deliver any further assurance, conveyance, act or deed necessary for the purpose. Not later than the effective date of any such appointment, the
Company shall file notice thereof in writing with the predecessor Rights Agent and each transfer agent of the Common Stock of the Company and the Preferred Stock, and give notice to the holders of the
Right Certificates by any means reasonably determined by the Company to inform such holders of such appointment (including without limitation, by including such information in one or more of the
Company's reports to shareholders or reports or filings with the Securities and Exchange Commission). Failure to give any notice provided for in this Section&nbsp;21, however, or any defect therein,
shall not affect the legality or validity of the resignation or removal of the Rights Agent or the appointment of the successor Rights Agent, as the case may be. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;22.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Issuance of New Right Certificates.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Notwithstanding any of the provisions of this Agreement
or of the Rights to the contrary, the Company may, at its option, issue new Right Certificates evidencing Rights in such form as may be approved by the Board of Directors of the Company to reflect any
adjustment or change in the Exercise Price per share and the number or kind or class of shares of stock or other securities or property purchasable under the Right Certificates made in accordance with
the provisions of this Agreement. In addition, in connection with the issuance or sale of shares of Common Stock of the Company following the Distribution Date and prior to the redemption or
expiration of the Rights, the Company (a)&nbsp;shall, with respect to shares of Common Stock of the Company so issued or sold pursuant to the exercise of stock options or under any employee plan or
arrangement, or upon the exercise, conversion or exchange of securities hereafter issued by the Company, and (b)&nbsp;may, in any other case, if deemed necessary or appropriate by the </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>28</FONT></P>

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<BR>

<P><FONT SIZE=2>Board
of Directors of the Company, issue Right Certificates representing the appropriate number of Rights in connection with such issuance or sale; </FONT><FONT SIZE=2><I>provided,
however,</I></FONT><FONT SIZE=2> that (i)&nbsp;no such Right Certificate shall be issued if, and to the extent that, the Company shall be advised by counsel that such issuance would create a
significant risk of material adverse tax consequences to the Company or the person to whom such Right Certificate would be issued, and (ii)&nbsp;no such Right Certificate shall be issued if, and to
the extent that, appropriate adjustments shall otherwise have been made in lieu of the issuance thereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;23.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Redemption.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;The
Board of Directors of the Company may, at its option, redeem all but not less than all of the then outstanding Rights at a redemption price of $0.01 per Right,
appropriately adjusted to reflect any stock dividend declared or paid, any subdivision or combination of the outstanding shares of Common Stock of the Company or any similar event occurring after the
date of this Agreement (such redemption price, as adjusted from time to time, being hereinafter referred to as the "Redemption Price"). The Rights may be redeemed only until the earlier to occur of
(i)&nbsp;the time at which any Person becomes an Acquiring Person or (ii)&nbsp;the Final Expiration Date. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;Immediately
upon the action of the Board of Directors of the Company ordering the redemption of the Rights in accordance with Section&nbsp;23 hereof, and without any
further action and without any notice, the right to exercise the Rights will terminate and the only right thereafter of the holders of Rights shall be to receive the Redemption Price for each Right so
held. Promptly after the action of the Board of Directors of the Company ordering the redemption of the Rights in accordance with Section&nbsp;23 hereof, the Company shall give notice of such
redemption to the Rights Agent and the holders of the then outstanding Rights by mailing such notice to the Rights Agent and to all such holders at their last addresses as they appear upon the
registry books of the Rights Agent or, prior to the Distribution Date, on the registry books of the Transfer Agent for the Common Stock of the Company. Any notice which is mailed in the manner herein
provided shall be deemed given, whether or not the holder receives the notice. The Company promptly shall mail a notice of any such exchange to all of the holders of such Rights at their last
addresses as they appear upon the registry books of the Rights Agent. Any notice which is mailed in the manner herein provided shall be deemed given, whether or not the holder receives the notice.
Each such notice of redemption will state the method by which the
payment of the Redemption Price will be made. Neither the Company nor any of its Affiliates or Associates may redeem, acquire or purchase for value any Rights at any time in any manner other than that
specifically set forth in this Section&nbsp;23 or Section&nbsp;24 hereof or in connection with the purchase of shares of Common Stock of the Company prior to the Distribution Date. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;&nbsp;The
Company may, at its option, pay the Redemption Price in cash, shares of Common Stock of the Company (based on the Fair Market Value of the Common Stock of the
Company as of the time of redemption) or any other form of consideration deemed appropriate by the Board of Directors of the Company. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;24.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Exchange.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;&nbsp;&nbsp;The
Board of Directors of the Company may, at its option, at any time on or after the occurrence of a Section&nbsp;11(a)(ii)&nbsp;Event, exchange
all or part of the then outstanding and exercisable Rights (which shall not include Rights that have become void pursuant to the provisions of Section&nbsp;7(e) hereof) for shares of Common Stock of
the Company at an exchange ratio of one share of Common Stock of the Company per Right, appropriately adjusted to reflect any stock split, stock dividend or similar transaction occurring after the
date hereof (such exchange ratio being hereinafter referred to as the "Section&nbsp;24(a)(i)&nbsp;Exchange Ratio"). Notwithstanding the foregoing, the Board of Directors of the Company shall not
be empowered to effect such exchange at any time after any Person (other than an Exempt Person), together with all Affiliates and </FONT></P>

</UL>
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<P><FONT SIZE=2>Associates
of such Person, becomes the Beneficial Owner of 50% or more of the Common Stock of the Company. </FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;Notwithstanding
the foregoing, the Board of Directors of the Company may, at its option, at any time on or after the occurrence of a
Section&nbsp;11(a)(ii)&nbsp;Event, exchange all or part of the then outstanding and exercisable Rights (which shall not include Rights that have become null and void pursuant to the provisions of
Section&nbsp;7(e) hereof) for shares of Common Stock of the Company at an exchange ratio specified in the following sentence, as appropriately adjusted to reflect any stock split, stock dividend or
similar transaction occurring after the date of this Agreement. Subject to the adjustment described in the foregoing sentence, each Right may be exchanged for that number of shares of Common Stock of
the Company obtained by dividing the Spread (as defined in Section&nbsp;11(a)(iii)) by the then Fair Market Value per one ten-thousandth of a share of Preferred Stock on the earlier of
(x)&nbsp;the date on which any person becomes an Acquiring Person or (y)&nbsp;the date on which a tender or exchange offer by any Person (other than an Exempt Person) is first published or sent or
given within the meaning of Rule&nbsp;14d-4(a) of the Exchange Act or any successor rule, if upon consummation thereof such Person could become an Acquiring Person (such exchange ratio
being referred to herein as the "Section&nbsp;24(a)(ii)&nbsp;Exchange Ratio"). Notwithstanding the foregoing, the Board of Directors of the Company shall not be empowered to effect such exchange
at any time after any Person (other than an Exempt Person), together with all Affiliates and Associates of such Person, becomes the Beneficial Owner of 50% or more of the Common Stock of the Company. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;Immediately
upon the action of the Board of Directors of the Company ordering the exchange of any Rights pursuant to subsection (a)&nbsp;of this Section&nbsp;24 and
without any further action and without any notice, the right to exercise such Rights pursuant to Section&nbsp;11(a)(ii)&nbsp;shall terminate and the only right thereafter of a holder of such
Rights shall be to receive that number of shares of Common Stock of the Company equal to the number of such Rights held by such holder multiplied by the Section&nbsp;24(a)(i)&nbsp;Exchange Ratio
or the Section&nbsp;24(a)(ii)&nbsp;Exchange Ratio, as applicable; </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that the holder of a Right exchanged pursuant to this
Section&nbsp;24 shall continue to have the right to purchase securities or other property of the Principal Party following a Section&nbsp;13 Event that has occurred or may thereafter occur. The
Company shall promptly give notice of any such exchange in accordance with Section&nbsp;26 hereof and shall promptly mail a notice of any such exchange to all of the holders of such Rights at their
last addresses as they appear upon the registry books of the Rights Agent; </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that the failure to give, or any defect in, such notice
shall not affect the validity of such exchange. Any notice which is mailed in the manner herein provided shall be deemed given, whether or not the holder receives the notice. Each such notice of
exchange will state the method by which the exchange of the shares of Common Stock of the Company for Rights will be effected and, in the event of any partial exchange, the number of Rights which will
be exchanged. Any partial exchange shall be effected pro rata based on the number of Rights (other than Rights which have become null and void pursuant to the provisions of Section&nbsp;7(e) hereof)
held by each holder of Rights. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(c)&nbsp;&nbsp;&nbsp;In
any exchange pursuant to this Section&nbsp;24, the Company, at its option, may substitute Preferred Stock (or Preferred Stock Equivalent, as such term is defined in
Section&nbsp;11(b) hereof) for Common Stock of the Company exchangeable for Rights, at the initial rate of one ten-thousandth of a share of Preferred Stock (or Preferred Stock
Equivalent) for each share of Common Stock of the Company, as appropriately adjusted to reflect adjustments in the voting rights of the Preferred Stock pursuant to the terms thereof, so that the
fraction of a share of Preferred Stock delivered in lieu of each share of Common Stock of the Company shall have the same voting rights as one share of Common Stock of the Company. </FONT></P>

</UL>
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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(d)&nbsp;&nbsp;&nbsp;In
the event that there shall not be sufficient shares of Common Stock of the Company or Preferred Stock (or Preferred Stock Equivalents) issued but not outstanding or
authorized but unissued to permit any exchange of Rights as contemplated in accordance with this Section&nbsp;24, the Company shall take all such action as may be necessary to authorize additional
shares of Common Stock of the Company or Preferred Stock (or Preferred Stock Equivalent) for issuance upon exchange of the Rights. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(e)&nbsp;&nbsp;&nbsp;The
Company shall not be required to issue fractions of Common Stock of the Company or to distribute certificates which evidence fractional shares of Common Stock of the
Company. If the Company elects not to issue such fractional shares of Common Stock of the Company, the Company shall pay, in lieu of such fractional shares of Common Stock of the Company, to the
registered holders of the Right Certificates with regard to which such fractional shares of Common Stock of the Company would otherwise be issuable, an amount in cash equal to the same fraction of the
Fair Market Value of
a whole share of Common Stock of the Company. For the purposes of this paragraph&nbsp;(e), the Fair Market Value of a whole share of Common Stock of the Company shall be the closing price of a share
of Common Stock of the Company (as determined pursuant to the second sentence of Section&nbsp;11(d)(i)&nbsp;hereof) for the Trading Day immediately prior to the date of exchange pursuant to this
Section&nbsp;24. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;25.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Notice of Certain Events.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(a)&nbsp;&nbsp;&nbsp;In
case the Company shall propose, at any time after the Distribution Date, (i)&nbsp;to pay any dividend payable in stock of any class to the holders of Preferred
Stock or to make any other distribution to the holders of Preferred Stock (other than a regular periodic cash dividend out of earnings or retained earnings of the Company), or (ii)&nbsp;to offer to
the holders of Preferred Stock rights or warrants to subscribe for or to purchase any additional shares of Preferred Stock or shares of stock of any class or any other securities, rights or options,
or (iii)&nbsp;to effect any reclassification of its Preferred Stock (other than a reclassification involving only the subdivision of outstanding shares of Preferred Stock), or (iv)&nbsp;to effect
any consolidation or merger into or with, or to effect any sale, mortgage or other transfer (or to permit one or more of its Subsidiaries to effect any sale, mortgage or other transfer), in one
transaction or a series of related transactions, of 50% or more of the assets or earning power of the Company and its Subsidiaries (taken as a whole) to, any other Person (other than a Subsidiary of
the Company in one or more transactions each of which is not prohibited by the proviso at the end of the first sentence of Section&nbsp;11(n) hereof), or (v)&nbsp;to effect the liquidation,
dissolution or winding up of the Company, or (vi)&nbsp;to declare or pay any dividend on the Common Stock of the Company payable in Common Stock of the Company or to effect a subdivision,
combination or consolidation of the Common Stock of the Company (by reclassification or otherwise than by payment of dividends in Common Stock of the Company) then in each such case, the Company shall
give to each holder of a Right Certificate and to the Rights Agent, in accordance with Section&nbsp;26 hereof, a notice of such proposed action, which shall specify the record date for the purposes
of such stock dividend, distribution of rights or warrants, or the date on which such reclassification, consolidation, merger, sale, transfer, liquidation, dissolution, or winding up is to take place
and the date of participation therein by the holders of the shares of Common Stock of the Company and/or Preferred Stock, if any such date is to be fixed, and such notice shall be so given in the case
of any action covered by clause&nbsp;(i) or (ii)&nbsp;above at least twenty (20)&nbsp;days prior to the record date for determining holders of the shares of Preferred Stock for purposes of such
action, and in the case of any such other action, at least twenty (20)&nbsp;days prior to the date of the taking of such proposed action or the date of participation therein by the holders of the
shares of Common Stock of the Company and/or Preferred Stock, whichever shall be the earlier; </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> no such notice shall be required
pursuant to this Section&nbsp;25 as a result of any Subsidiary of the Company effecting a consolidation or merger with or into, or effecting a sale or other transfer of assets or earnings power to,
any </FONT></P>

</UL>
<P ALIGN="CENTER"><FONT SIZE=2>31</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<A NAME="page_kl2260_1_32"> </A>
<UL>

<P><FONT SIZE=2>other
Subsidiary of the Company in a manner not inconsistent with the provisions of this Agreement. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(b)&nbsp;&nbsp;&nbsp;In
case any Section&nbsp;11(a)(ii)&nbsp;Event shall occur, then, in any such case, the Company shall as soon as practicable thereafter give to each registered holder
of a Right Certificate and to the Rights Agent, in
accordance with Section&nbsp;26 hereof, a notice of the occurrence of such event, which shall specify the event and the consequences of the event to holders of Rights under
Section&nbsp;11(a)(ii)&nbsp;hereof. </FONT></P>

</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;26.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Notices.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Notices or demands authorized by this Agreement to be given or made by the Rights
Agent or by the holder of any Right Certificate to or on the Company shall be sufficiently given or made if sent by first-class mail, postage prepaid, by facsimile transmission or by
nationally-recognized overnight courier addressed (until another address is filed in writing with the Rights Agent) as follows: </FONT></P>

<UL>
<UL>

<P><FONT SIZE=2>AVANT
Immunotherapeutics,&nbsp;Inc.<BR>
119 Fourth Avenue<BR>
Needham, MA 02494<BR>
Facsimile No. (781)&nbsp;433-0262<BR>
Attention: Avery W. Catlin </FONT></P>

</UL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Subject
to the provisions of Section&nbsp;21, any notice or demand authorized by this Agreement to be given or made by the Company or by the holder of any Right Certificate to or on
the Rights Agent shall be sufficiently given or made if sent by first-class mail, postage prepaid, by facsimile transmission or by nationally-recognized overnight courier addressed (until another
address is filed in writing with the Company) as follows: </FONT></P>

<UL>
<UL>

<P><FONT SIZE=2>EquiServe
Trust Company, N.A.<BR>
250 Royall Street<BR>
Canton, MA 02021<BR>
Facsimile No. (781)&nbsp;575-2549<BR>
Attention: Client Administration </FONT></P>

</UL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Notices
or demands authorized by this Agreement to be given or made by the Company or the Rights Agent to the holder of any Right Certificate (or, prior to the Distribution Date, to the
holder of any certificate representing shares of Common Stock of the Company) shall be sufficiently given or made if sent by first-class mail, postage prepaid, addressed to such holder at the address
of such holder as shown on the registry books of the Company. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;27.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Supplements and Amendments.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Prior to the occurrence of a
Section&nbsp;11(a)(ii)&nbsp;Event, the Company and the Rights Agent shall, if the Board of Directors of the Company so directs, supplement or amend any provision of this Agreement as the Board of
Directors of the Company may deem necessary or desirable without the approval of any holders of certificates representing shares of Common Stock of the Company. From and after the occurrence of a
Section&nbsp;11(a)(ii)&nbsp;Event, the Company and the Rights Agent shall, if the Board of Directors of the Company so directs, supplement or amend this Agreement without the approval of any
holder of Right Certificates in order (i)&nbsp;to cure any ambiguity, (ii)&nbsp;to correct or supplement any provision contained herein which may be defective or inconsistent with any other
provisions herein, (iii)&nbsp;to shorten or lengthen any time period hereunder, or (iv)&nbsp;to change or supplement the provisions hereof in any manner which the Board of Directors of the Company
may deem necessary or desirable and which shall not adversely affect the interests of the holders of Right Certificates (other than an Acquiring Person or any Affiliate or Associate of an Acquiring
Person); </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that from and after the occurrence of a Section&nbsp;11(a)(ii)&nbsp;Event this Agreement may not be supplemented or
amended to lengthen, pursuant to clause&nbsp;(iii) of this sentence, (A)&nbsp;a time period relating to when the Rights may be redeemed at such time as the Rights </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>32</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
<!-- ZEQ.=5,SEQ=35,EFW="2146122",CP="AVANT IMMUNOTHERAPEUTICS,INC.",DN="3",CHK=186025,FOLIO='32',FILE='DISK006:[04BOS0.04BOS2260]KL2260A.;7',USER='DPERRY',CD=';8-NOV-2004;11:52' -->
<A NAME="page_kl2260_1_33"> </A>
<BR>

<P><FONT SIZE=2>are
not then redeemable or (B)&nbsp;any other time period unless such lengthening is for the purpose of protecting, enhancing or clarifying the rights of, and the benefits to, the holders of Rights
(other than an Acquiring Person or any Affiliate or Associate of an Acquiring Person). Without limiting the foregoing, the Company may at any time prior to the occurrence of a
Section&nbsp;11(a)(ii)&nbsp;Event amend this Agreement to lower the threshold set forth in Section&nbsp;1(a) to not less than the greater of (i)&nbsp;the sum of .001% and the largest
percentage of the outstanding Common Stock of the Company then known by the Company to be Beneficially Owned by any Person (other than the Company, any Subsidiary of the Company, any employee benefit
plan of the Company or any Subsidiary of the Company, or any entity holding Common Stock of the Company for or pursuant to the terms of any such plan) and (ii)&nbsp;10%. Upon the delivery of such
certificate from an appropriate officer of the Company which states that the proposed supplement or amendment is in compliance with the terms of this Section&nbsp;27, the Rights Agent shall execute
such supplement or amendment, and any failure of the Rights Agent to so execute such supplement or amendment shall not affect the validity of the actions taken by the Board of Directors of the Company
pursuant to this Section&nbsp;27. Prior to the occurrence of a Section&nbsp;11(a)(ii)&nbsp;Event, the interests of the holders of Rights shall be deemed coincident with the interests of the
holders of Common Stock of the Company. Notwithstanding any other provision hereof, the Rights Agent's consent must be obtained regarding any amendment or supplement pursuant to this Section&nbsp;27
which alters the Rights Agent's rights or duties. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;28.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Successors.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;All the covenants and provisions of this Agreement by or for the benefit of the
Company or the Rights Agent shall bind and inure to the benefit of their respective successors and assigns hereunder. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;29.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Determinations and Actions by the Board of Directors.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The Board of Directors of the Company
shall have the exclusive power and authority to administer this Agreement and to exercise all rights and powers specifically granted to the Board of Directors or to the Company, or as may be necessary
or advisable in the administration of this Agreement, including without limitation, the right and power to (i)&nbsp;interpret the provisions of this Agreement and (ii)&nbsp;make all determinations
and computations deemed necessary or advisable for the administration of this Agreement (including a determination to redeem or not redeem the Rights or to amend the Agreement). All such actions,
calculations, interpretations
and determinations (including, for purposes of clause&nbsp;(y) below, all omissions with respect to the foregoing) which are done or made by the Board of Directors in good faith shall (x)&nbsp;be
final, conclusive and binding on the Company, the Rights Agent, the holders of the Rights and all other parties, and (y)&nbsp;not subject any member of the Board of Directors to any liability to the
holders of the Rights or to any other person. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;30.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Benefits of this Agreement.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Nothing in this Agreement shall be construed to give to any
person or corporation other than the Company, the Rights Agent and the registered holders of the Right Certificates (and, prior to the Distribution Date, the Common Stock of the Company) any legal or
equitable right, remedy or claim under this Agreement; but this Agreement shall be for the sole and exclusive benefit of the Company, the Rights Agent and the registered holders of the Right
Certificates (and, prior to the Distribution Date, registered holders of the Common Stock of the Company). </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;31.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Severability.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;If any term, provision, covenant or restriction of this Agreement is held by a
court of competent jurisdiction or other authority to be invalid, void or unenforceable, the remainder of the terms, provisions, covenants and restrictions of this Agreement shall remain in full force
and effect and shall in no way be affected, impaired or invalidated; </FONT><FONT SIZE=2><I>provided, however,</I></FONT><FONT SIZE=2> that notwithstanding anything in this Agreement to the contrary,
if any such term, provision, covenant or restriction is held by such court or authority to be invalid, void or unenforceable and the Board of Directors of the Company determines in its good faith
judgment that severing the invalid language from the Agreement would adversely affect the purpose or effect of the Agreement, the right of redemption set forth in Section&nbsp;23 hereof shall be
reinstated and shall not expire until the Close of Business on the tenth day following the date of such determination by the Board of Directors. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>33</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<A NAME="page_kl2260_1_34"> </A>
<BR>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;32.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Governing Law.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;This Agreement, each Right and each Right Certificate issued hereunder shall
be deemed to be a contract made under the laws of the State of Delaware and for all purposes shall be governed by and construed in accordance with the laws of such State applicable to contracts to be
made and to be performed entirely within such State. The courts of the State of Delaware and of the United States of America located in the State of Delaware (the "Delaware Courts") shall have
exclusive jurisdiction over any litigation arising out of or relating to this Agreement and the transactions contemplated hereby, and any Person commencing or otherwise involved in any such litigation
shall waive any objection to the laying of venue of such litigation in the Delaware Courts and shall not plead or claim in any Delaware Court that such litigation brought therein has been brought in
an inconvenient forum. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;33.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Counterparts.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;This Agreement may be executed in any number of counterparts and each of such
counterparts shall for all purposes be deemed to be an original, and all such counterparts shall together constitute but one and the same instrument. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;34.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Descriptive Headings.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Descriptive headings of the several Sections of this Agreement are
inserted for convenience only and shall not control or affect the meaning or construction of any of the provisions hereof. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;35.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Force Majeure.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Notwithstanding anything to the contrary contained herein, neither the Company
nor the Rights Agent shall be liable for any delay or failure in performance resulting directly from any act or event beyond its reasonable control and without the fault or gross negligence of the
delayed or non-performing party that causes a sudden, substantial or widespread disruption in business activities, including, without limitation, fire, flood, natural disaster or act of
God, strike or other industrial disturbance, war (declared or undeclared), embargo, blockade, legal restriction, riot, insurrection, act of terrorism, disruption in transportation, communications,
electric power or other utilities, or other vital infrastructure or any means of disrupting or damaging internet or other computer networks or facilities (each, a </FONT><FONT SIZE=2><I>"Force
Majeure Condition"</I></FONT><FONT SIZE=2>); </FONT><FONT SIZE=2><I>provided,</I></FONT><FONT SIZE=2> that such delayed or non-performing party shall use reasonable commercial efforts to
resume performance as soon as practicable. If any Force Majeure Condition occurs, the party delayed or unable to perform shall give immediate written notice to the other party, stating the nature of
the Force Majeure Condition and any action being taken to avoid or minimize its effect. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>[Remainder
of page intentionally left blank] </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>34</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;IN
WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly executed as an instrument under seal and attested, all as of the day and year first above written. </FONT></P>

<!-- User-specified TAGGED TABLE -->
<TABLE WIDTH="76%" BORDER=0 CELLSPACING=0 CELLPADDING=0>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2>ATTEST:</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD COLSPAN=2><FONT SIZE=2>AVANT Immunotherapeutics,&nbsp;Inc.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2><BR>
By:&nbsp;&nbsp;</FONT><HR NOSHADE></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="4%"><FONT SIZE=2><BR>
By:</FONT></TD>
<TD WIDTH="54%"><BR><HR NOSHADE><FONT SIZE=2> Name: Una S. Ryan, Ph.D., O.B.E.<BR>
Title: Chief Executive Officer</FONT></TD>
</TR>
</TABLE>
<!-- end of user-specified TAGGED TABLE -->

<!-- User-specified TAGGED TABLE -->
<TABLE WIDTH="76%" BORDER=0 CELLSPACING=0 CELLPADDING=0>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2>ATTEST:</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD COLSPAN=2><FONT SIZE=2>EquiServe Trust Company, N.A.,<BR>
as Rights Agent</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="39%"><FONT SIZE=2><BR>
By:&nbsp;&nbsp;</FONT><HR NOSHADE></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="4%"><FONT SIZE=2><BR>
By:</FONT></TD>
<TD WIDTH="54%"><BR><HR NOSHADE><FONT SIZE=2> Name:<BR>
Title:</FONT></TD>
</TR>
</TABLE>
<!-- end of user-specified TAGGED TABLE -->

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<!-- THIS IS THE END OF A COMPOSITION COMPONENT -->
<P ALIGN="CENTER"><FONT SIZE=2><A
NAME="page_km2260_1_1"> </A> </FONT> <FONT SIZE=2><B>Exhibit&nbsp;A  </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>CERTIFICATE OF DESIGNATIONS, PREFERENCES<BR>
AND RIGHTS OF A SERIES OF<BR>
PREFERRED STOCK<BR>
OF<BR>
AVANT IMMUNOTHERAPEUTICS,&nbsp;INC.  </B></FONT></P>

<HR NOSHADE ALIGN="CENTER" WIDTH="120">

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;AVANT
IMMUNOTHERAPEUTICS,&nbsp;INC., a corporation organized and existing under the General Corporation Law of the State of Delaware, </FONT></P>

<P><FONT SIZE=2>DOES
HEREBY CERTIFY: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;That,
pursuant to authority conferred upon the Board of Directors by the Third Restated Certificate of Incorporation, as amended, of said corporation, and pursuant to the provisions of
Section&nbsp;151 of Title 8 of the Delaware Code of 1953, said Board of Directors, at a meeting duly held on November&nbsp;5, 2004, adopted a resolution providing for the designations, preferences
and relative, participating, optional or other rights, and the qualifications, limitations or restrictions thereof, of a Series of Preferred Stock, which resolution is as follows: </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>See
attached pages 2A-7A </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>1-A</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<A NAME="page_km2260_1_2"> </A>
<P ALIGN="CENTER"><FONT SIZE=2><B>VOTE OF DIRECTORS ESTABLISHING<BR>
SERIES C-1 JUNIOR PARTICIPATING CUMULATIVE<BR>
PREFERRED STOCK<BR>
of<BR>
AVANT IMMUNOTHERAPEUTICS,&nbsp;INC.  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Pursuant to Section&nbsp;151 of the General Corporation Law of the State of Delaware: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;VOTED,
that pursuant to authority conferred upon and vested in the Board of Directors by the Third Restated Certificate of Incorporation, as amended (the "Certificate of Incorporation"),
of AVANT Immunotherapeutics,&nbsp;Inc. (the "Corporation"), the Board of Directors hereby establishes and designates a series of Preferred Stock of the Corporation, and hereby fixes and determines
the relative rights and preferences of the shares of such series, in addition to those set forth in the Certificate of Incorporation, as follows: </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;1.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Designation and Amount.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The shares of such series shall be designated as
"Series&nbsp;C-1 Junior Participating Cumulative Preferred Stock" (the "Series&nbsp;C-1 Preferred Stock"), and the number of shares initially constituting such series shall
be 150,000; provided, however, that if more than a total of 150,000 shares of Series&nbsp;C-1 Preferred Stock shall be issuable upon the exercise of Rights (the "Rights") issued pursuant
to the Shareholder Rights Agreement dated as of November&nbsp;5 2004, between the Corporation and EquiServe Trust Company, N.A., as Rights Agent (the "Rights Agreement"), the Board of Directors of
the Corporation, pursuant to Section&nbsp;151(g) of the General Corporation Law of the State of Delaware, may direct by resolution or resolutions that a certificate be properly executed,
acknowledged, filed and recorded, in accordance with the provisions of Section&nbsp;103 thereof, providing for the total number of shares of Series&nbsp;C-1 Preferred Stock authorized
to be issued to be increased (to the extent that the Certificate of Incorporation then permits) to the largest number of whole shares (rounded up to the nearest whole number) issuable upon exercise of
such Rights. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;2.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Dividends and Distributions.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(A)</FONT></DT><DD><FONT SIZE=2>(i)
Subject to the rights of the holders of any shares of any series of preferred stock (or any similar stock) ranking prior and superior to the Series&nbsp;C-1
Preferred Stock with respect to dividends, the holders of shares of Series&nbsp;C-1 Preferred Stock, in preference to the holders of shares of common stock and of any other junior stock,
shall be entitled to receive, when, as and if declared by the Board of Directors out of funds legally available for the purpose, quarterly dividends payable in cash on the first day of March, June,
September and December in each year (each such date being referred to herein as a "Quarterly Dividend Payment Date"), commencing on the first Quarterly Dividend Payment Date after the first issuance
of a share or fraction of a share of Series&nbsp;C-1 Preferred Stock, in an amount per share (rounded to the nearest cent) equal to the greater of (a)&nbsp;$1.00 or (b)&nbsp;subject
to the provisions for adjustment hereinafter set forth, 10,000 times the aggregate per share amount of all cash dividends, and 10,000 times the aggregate per share amount (payable in kind) of all
non-cash dividends or other distributions other than a dividend payable in shares of common stock or a subdivision of the outstanding shares of common stock (by reclassification or
otherwise), declared on the common stock since the immediately preceding Quarterly Dividend Payment Date, or, with respect to the first Quarterly Dividend Payment Date, since the first issuance of any
share or fraction of a share of Series&nbsp;C-1 Preferred Stock. The multiple of cash and non-cash dividends declared on the common stock to which holders of the
Series&nbsp;C-1 Preferred Stock are entitled, which shall be 10,000 initially but which shall be adjusted from time to time as hereinafter provided, is hereinafter referred to as the
"Dividend Multiple." In the event the Corporation shall at any time after November&nbsp;5, 2004 (the "Rights Declaration Date") (i)&nbsp;declare or pay any dividend on common stock payable in
shares of common stock, or (ii)&nbsp;effect a subdivision or combination or consolidation of the outstanding shares of </FONT></DD></DL>
</UL>
<P ALIGN="CENTER"><FONT SIZE=2>2-A</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<A NAME="page_km2260_1_3"> </A>
<UL>
<UL>

<P><FONT SIZE=2>common
stock (by reclassification or otherwise than by payment of a dividend in shares of common stock) into a greater or lesser number of shares of common stock, then in each such case the Dividend
Multiple thereafter applicable to the determination of the amount of dividends which holders of shares of Series&nbsp;C-1 Preferred Stock shall be entitled to receive shall be the
Dividend Multiple applicable immediately prior to such event multiplied by a fraction, the numerator of which is the number of shares of common stock outstanding immediately after such event and the
denominator of which is the number of shares of common stock that were outstanding immediately prior to such event. </FONT></P>

</UL>
</UL>
<UL>
<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;&nbsp;Notwithstanding
anything else contained in this paragraph&nbsp;(A), the Corporation shall, out of funds legally available for that purpose, declare a dividend or
distribution on the Series&nbsp;C-1 Preferred Stock as provided in this paragraph&nbsp;(A) immediately after it declares a dividend or distribution on the common stock (other than a
dividend payable in shares of common stock); provided that, in the event no dividend or distribution shall have been declared on the common stock during the period between any Quarterly Dividend
Payment Date and the next subsequent Quarterly Dividend Payment Date, a dividend of $1.00 per share on the Series&nbsp;C-1 Preferred Stock shall nevertheless be payable on such
subsequent Quarterly Dividend Payment Date. </FONT></P>

</UL>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(B)</FONT></DT><DD><FONT SIZE=2>Dividends
shall begin to accrue and be cumulative on outstanding shares of Series&nbsp;C-1 Preferred Stock from the Quarterly Dividend Payment Date next preceding the
date of issue of such shares of Series&nbsp;C-1 Preferred Stock, unless the date of issue of such shares is prior to the record date for the first Quarterly Dividend Payment Date, in
which case dividends on such shares shall begin to accrue from the date of issue of such shares, or unless the date of issue is a Quarterly Dividend Payment Date or is a date after the record date for
the determination of holders of shares of Series&nbsp;C-1 Preferred Stock entitled to receive a quarterly dividend and before such Quarterly Dividend Payment Date, in either of which
events such dividends shall begin to accrue and be cumulative from such Quarterly Dividend Payment Date. Accrued but unpaid dividends shall not bear interest. Dividends paid on the shares of
Series&nbsp;C-1 Preferred Stock in an amount less than the total amount of such dividends at the time accrued and payable on such shares shall be allocated pro rata on a
share-by-share basis among all such shares at the time outstanding. The Board of Directors may fix in accordance with applicable law a record date for the determination of
holders of shares of Series&nbsp;C-1 Preferred Stock entitled to receive payment of a dividend or distribution declared thereon, which record date shall be not more than such number of
days prior to the date fixed for the payment thereof as may be allowed by applicable law. </FONT></DD></DL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;3.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Voting Rights.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;In addition to any other voting rights required by law, the holders of shares
of Series&nbsp;C-1 Preferred Stock shall have the following voting rights: </FONT></P>

<UL>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(A)</FONT></DT><DD><FONT SIZE=2>Subject
to the provision for adjustment hereinafter set forth, each share of Series&nbsp;C-1 Preferred Stock shall entitle the holder thereof to 10,000 votes on all
matters submitted to a vote of the stockholders of the Corporation. The number of votes which a holder of a share of Series&nbsp;C-1 Preferred Stock is entitled to cast, which shall
initially be 10,000 but which may be adjusted from time to time as hereinafter provided, is hereinafter referred to as the "Vote Multiple." In the event the Corporation shall at any time after the
Rights Declaration Date (i)&nbsp;declare or pay any dividend on common stock payable in shares of common stock, or (ii)&nbsp;effect a subdivision or combination or consolidation of the outstanding
shares of common stock (by reclassification or otherwise than by payment of a dividend in shares of common stock) into a greater or lesser number of shares of common stock, then in each such case the
Vote Multiple thereafter applicable to the determination of the number of votes per share to which holders of shares of Series&nbsp;C-1 Preferred Stock shall be entitled shall be the
Vote Multiple immediately prior to such event multiplied by a fraction, the numerator of which is </FONT></DD></DL>
</UL>
<P ALIGN="CENTER"><FONT SIZE=2>3-A</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<A NAME="page_km2260_1_4"> </A>
<UL>
<UL>

<P><FONT SIZE=2>the
number of shares of common stock outstanding immediately after such event and the denominator of which is the number of shares of common stock that were outstanding immediately prior to such
event. </FONT></P>

</UL>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(B)</FONT></DT><DD><FONT SIZE=2>Except
as otherwise provided herein or by law, the holders of shares of Series&nbsp;C-1 Preferred Stock and the holders of shares of common stock and the holders of
shares of any other capital stock of this Corporation having general voting rights, shall vote together as one class on all matters submitted to a vote of stockholders of the Corporation.
<BR><BR></FONT></DD><DT style='margin-bottom:-11pt;'><FONT SIZE=2>(C)</FONT></DT><DD><FONT SIZE=2>Except
as otherwise required by applicable law or as set forth herein, holders of Series&nbsp;C-1 Preferred Stock shall have no special voting rights and their consent
shall not be required (except to the extent they are entitled to vote with holders of common stock as set forth herein) for taking any corporate action. </FONT></DD></DL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;4.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Certain Restrictions.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT></P>

<UL>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(A)</FONT></DT><DD><FONT SIZE=2>Whenever
dividends or distributions payable on the Series&nbsp;C-1 Preferred Stock as provided in Section&nbsp;2 are in arrears, thereafter and until all accrued and
unpaid dividends and distributions, whether or not declared, on shares of Series&nbsp;C-1 Preferred Stock outstanding shall have been paid in full, the Corporation shall not: </FONT></DD></DL>
</UL>
<UL>
<UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(i)&nbsp;&nbsp;&nbsp;&nbsp;declare
or pay dividends on, make any other distributions on, or redeem or purchase or otherwise acquire for consideration any shares of stock ranking junior (either as
to dividends or upon liquidation, dissolution or winding up) to the Series&nbsp;C-1 Preferred Stock; </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(ii)&nbsp;&nbsp;&nbsp;declare
or pay dividends on or make any other distributions on any shares of stock ranking on a parity (either as to dividends or upon liquidation, dissolution or
winding up) with the Series&nbsp;C-1 Preferred Stock, except dividends paid ratably on the Series&nbsp;C-1 Preferred Stock and all such parity stock on which dividends are
payable or in arrears in proportion to the total amounts to which the holders of all such shares are then entitled; </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iii)&nbsp;&nbsp;except
as permitted in subsection 4(A)(iv)&nbsp;below, redeem, purchase or otherwise acquire for consideration shares of any stock ranking on a parity (either as to
dividends or upon liquidation, dissolution or winding up) with the Series&nbsp;C-1 Preferred Stock, provided that the Corporation may at any time redeem, purchase or otherwise acquire
shares of any such parity stock in exchange for shares of any stock of the Corporation ranking junior (either as to dividends or upon dissolution, liquidation or winding up) to the
Series&nbsp;C-1 Preferred Stock; or </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(iv)&nbsp;&nbsp;purchase
or otherwise acquire for consideration any shares of Series&nbsp;C-1 Preferred Stock, or any shares of any stock ranking on a parity (either as
to dividends or upon liquidation,
dissolution or winding up) with the Series&nbsp;C-1 Preferred Stock, except in accordance with a purchase offer made in writing or by publication (as determined by the Board of
Directors) to all holders of such shares upon such terms as the Board of Directors, after consideration of the respective annual dividend rates and other relative rights and preferences of the
respective series and classes, shall determine in good faith will result in fair and equitable treatment among the respective series or classes. </FONT></P>

</UL>
<DL compact>
<DT style='margin-bottom:-11pt;'><FONT SIZE=2>(B)</FONT></DT><DD><FONT SIZE=2>The
Corporation shall not permit any subsidiary of the Corporation to purchase or otherwise acquire for consideration any shares of stock of the Corporation unless the Corporation
could, under subsection (A)&nbsp;of this Section&nbsp;4, purchase or otherwise acquire such shares at such time and in such manner. </FONT></DD></DL>
</UL>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;5.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Reacquired Shares.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Any shares of Series&nbsp;C-1 Preferred Stock purchased or
otherwise acquired by the Corporation in any manner whatsoever shall be retired and canceled promptly after the acquisition thereof. All such shares shall upon their cancellation become authorized but
unissued shares of preferred stock and may be reissued as part of a new series of preferred stock to be created by </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>4-A</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<BR>

<P><FONT SIZE=2>resolution
or resolutions of the Board of Directors, subject to the conditions and restrictions on issuance set forth herein. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;6.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Liquidation, Dissolution or Winding Up.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Upon any liquidation (voluntary or otherwise),
dissolution or winding up of the Corporation, no distribution shall be made (x)&nbsp;to the holders of shares of stock ranking junior (either as to dividends or upon liquidation, dissolution or
winding up) to the Series&nbsp;C-1 Preferred Stock unless, prior thereto, the holders of shares of Series&nbsp;C-1 Preferred Stock shall have received an amount equal to
accrued and unpaid dividends and distributions thereon, whether or not declared, to the date of such payment, plus an amount equal to the greater of (1)&nbsp;$10,000.00 per share or (2)&nbsp;an
aggregate amount per share, subject to the provision for adjustment hereinafter set forth, equal to 10,000 times the aggregate amount to be distributed per share to holders of common stock, or
(y)&nbsp;to the holders of stock ranking on a parity (either as to dividends or upon liquidation, dissolution or winding up) with the Series&nbsp;C-1 Preferred Stock, except
distributions made ratably on the Series&nbsp;C-1 Preferred Stock and all other such parity stock in proportion to the total amounts to which the holders of all such shares are entitled
upon such liquidation, dissolution or winding up. In the event the Corporation shall at any time after the Rights Declaration Date (i)&nbsp;declare or pay any dividend on common stock payable in
shares of common stock, or (ii)&nbsp;effect a subdivision or combination or consolidation of the outstanding shares of common stock (by reclassification or otherwise than by payment of a dividend in
shares of common stock) into a greater or lesser number of shares of common stock, then in each such case the aggregate amount per share to which holders of shares of Series&nbsp;C-1
Preferred Stock were entitled immediately prior to such event under clause&nbsp;(x) of the preceding sentence shall be adjusted by multiplying such amount by a fraction, the numerator of which is
the number of shares of
common stock outstanding immediately after such event and the denominator of which is the number of shares of common stock that were outstanding immediately prior to such event. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Neither
the consolidation of nor merging of the Corporation with or into any other corporation or corporations, nor the sale or other transfer of all or substantially all of the assets
of the Corporation, shall be deemed to be a liquidation, dissolution or winding up of the Corporation within the meaning of this Section&nbsp;6. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;7.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Consolidation, Merger, etc.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;In case the Corporation shall enter into any consolidation,
merger, combination or other transaction in which the shares of common stock are exchanged for or changed into other stock or securities, cash and/or any other property, then in any such case the
shares of Series&nbsp;C-1 Preferred Stock shall at the same time be similarly exchanged or changed in an amount per share (subject to the provision for adjustment hereinafter set forth)
equal to 10,000 times the aggregate amount of stock, securities, cash and/or any other property (payable in kind), as the case may be, into which or for which each share of common stock is changed or
exchanged, plus accrued and unpaid dividends, if any, payable with respect to the Series&nbsp;C-1 Preferred Stock. In the event the Corporation shall at any time after the Rights
Declaration Date (i)&nbsp;declare or pay any dividend on common stock payable in shares of common stock, or (ii)&nbsp;effect a subdivision or combination or consolidation of the outstanding shares
of common stock (by reclassification or otherwise than by payment of a dividend in shares of common stock) into a greater or lesser number of shares of common stock, then in each such case the amount
set forth in the preceding sentence with respect to the exchange or change of shares of Series&nbsp;C-1 Preferred Stock shall be adjusted by multiplying such amount by a fraction, the
numerator of which is the number of shares of common stock outstanding immediately after such event and the denominator of which is the number of shares of common stock that were outstanding
immediately prior to such event. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;8.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Redemption.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The shares of Series&nbsp;C-1 Preferred Stock shall not be
redeemable; provided, however, that the foregoing shall not limit the ability of the Corporation to purchase or otherwise deal in such shares to the extent otherwise permitted hereby and by law. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>5-A</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<BR>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;9.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Ranking.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Unless otherwise expressly provided in the Certificate of Incorporation or a
Certificate of Designations relating to any other series of preferred stock of the Corporation, the Series&nbsp;C-1 Preferred Stock shall rank junior to every other series of the
Corporation's preferred stock previously or hereafter authorized, as to the payment of dividends and the distribution of assets on liquidation, dissolution or winding up and shall rank senior to the
common stock. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;10.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Amendment.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;The Certificate of Incorporation and this Certificate of Designations shall not be
amended in any manner which would materially alter or change the powers, preferences or special rights of the Series&nbsp;C-1 Preferred Stock so as to affect them adversely without the
affirmative vote of the holders of two-thirds or more of the outstanding shares of Series&nbsp;C-1 Preferred Stock, voting separately as a class. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Section&nbsp;11.</FONT><FONT
SIZE=2><I>&nbsp;&nbsp;&nbsp;&nbsp;Fractional Shares.</I></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;Series&nbsp;C-1 Preferred Stock may be issued in whole
shares or in any fraction of a share that is one ten-thousandth (1/10,000th) of a share or any integral multiple of such fraction, which shall entitle the holder, in proportion to such
holder's fractional shares, to exercise voting rights, receive dividends, participate in distributions and to have the benefit of all other rights of holders of Series&nbsp;C-1 Preferred
Stock. In lieu of fractional shares, the Corporation may elect to make a cash payment as provided in the Rights Agreement for fractions of a share other than one ten-thousandth
(1/10,000th) of a share or any integral multiple thereof. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>6-A</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<!-- THIS IS THE END OF A COMPOSITION COMPONENT -->
<P ALIGN="RIGHT"><FONT SIZE=2><B>Exhibit&nbsp;A  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;I,
<U>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</U>,
<U>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</U>, do make this certificate, hereby declaring and certifying that this is my act and deed on
behalf of the Corporation this <U>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;</U> day of November, 2004. </FONT></P>

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<TD WIDTH="53%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="45%"><BR><HR NOSHADE><FONT SIZE=2> By:<BR>
Title</FONT></TD>
</TR>
</TABLE>
<!-- end of user-specified TAGGED TABLE -->

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<!-- THIS IS THE END OF A COMPOSITION COMPONENT -->
<P ALIGN="CENTER"><FONT SIZE=2><B>Exhibit&nbsp;B  </B></FONT></P>

<P><FONT SIZE=2>[Form
of Right Certificate] </FONT></P>

<P><FONT SIZE=2>Certificate
No.&nbsp;R-______ Rights </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;NOT
EXERCISABLE AFTER NOVEMBER 11, 2014 OR EARLIER IF NOTICE OF REDEMPTION IS GIVEN. THE RIGHTS ARE SUBJECT TO REDEMPTION, AT THE OPTION OF AVANT IMMUNOTHERAPEUTICS,&nbsp;INC., AT
$0.01 PER RIGHT, ON THE TERMS SET FORTH IN THE SHAREHOLDER RIGHTS AGREEMENT BETWEEN AVANT IMMUNOTHERAPEUTICS,&nbsp;INC. AND EQUISERVE TRUST COMPANY, N.A., AS RIGHTS AGENT, DATED AS OF NOVEMBER 5,
2004 (THE "RIGHTS AGREEMENT"). UNDER CERTAIN CIRCUMSTANCES SPECIFIED IN SECTION 7(e) OF THE RIGHTS AGREEMENT, RIGHTS BENEFICIALLY OWNED BY AN ACQUIRING PERSON OR AN ASSOCIATE OR AFFILIATE OF AN
ACQUIRING PERSON (AS SUCH TERMS ARE DEFINED IN THE RIGHTS AGREEMENT) AND ANY SUBSEQUENT HOLDER OF SUCH RIGHTS MAY BECOME NULL AND VOID. </FONT></P>

<P><FONT SIZE=2>Right
Certificate </FONT></P>

<P><FONT SIZE=2>AVANT
IMMUNOTHERAPEUTICS,&nbsp;INC. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;This
certifies that __________________, or registered assigns, is the registered owner of the number of Rights set forth above, each of which entitles the owner thereof, subject to the
terms, provisions and conditions of the Shareholder Rights Agreement dated as of November&nbsp;5, 2004 (the "Rights Agreement") between AVANT Immunotherapeutics,&nbsp;Inc. (the "Company") and
EquiServe Trust Company, N.A., as Rights Agent (the "Rights Agent"), to purchase from the Company at any time after the Distribution Date (as such term is defined in the Rights Agreement) and prior to
the close of business on November&nbsp;11, 2014 at the office or offices of the Rights Agent designated for such purpose, or its successors as Rights Agent, one ten-thousandth of a fully
paid, non-assessable share of the Series&nbsp;C-1 Junior Participating Cumulative Preferred Stock (the "Preferred Stock") of the Company, at a purchase price of $_________
per one ten-thousandth of a share (the "Exercise Price"), upon presentation and surrender of this Right Certificate with the Form of Election to Purchase and the related Certificate duly
executed.
The number of Rights evidenced by this Right Certificate (and the number of shares which may be purchased upon exercise thereof) set forth above, and the Exercise Price per share set forth above, are
the number and Exercise Price as of __________, based on the Preferred Stock as constituted at such date. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Upon
the occurrence of a Section&nbsp;11(a)(ii)&nbsp;Event (as such term is defined in the Rights Agreement), if the Rights evidenced by this Right Certificate are beneficially owned
by (i)&nbsp;an Acquiring Person or an Affiliate or Associate of any such Person (as such terms are defined in the Rights Agreement), (ii)&nbsp;a transferee of any such Acquiring Person or
Associate or Affiliate thereof, or (iii)&nbsp;under certain circumstances specified in the Rights Agreement, a transferee of a Person who, after such transfer, became an Acquiring Person or an
Affiliate or Associate of an Acquiring Person, such Rights shall become null and void and no holder hereof shall have any right with respect to such Rights from and after the occurrence of such
Section&nbsp;11(a)(ii)&nbsp;Event. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;As
provided in the Rights Agreement, the Exercise Price and the number of shares of Preferred Stock or other securities which may be purchased upon the exercise of the Rights evidenced
by this Right Certificate are subject to modification and adjustment upon the happening of certain events. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;This
Right Certificate is subject to all of the terms, provisions and conditions of the Rights Agreement, which terms, provisions and conditions are hereby incorporated herein by
reference and made a part hereof and to which Rights Agreement reference is hereby made for a full description of the rights, limitations of rights, obligations, duties and immunities hereunder of the
Rights Agent, the Company and the holders of the Right Certificates, which limitations of rights include the temporary suspension of the exercisability of such Rights under the specific circumstances
set forth in the Rights Agreement. Copies of the Rights Agreement are on file at the principal office of the Company and the </FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<A NAME="page_ko2260_1_2"> </A>
<BR>

<P><FONT SIZE=2>designated
office of the Rights Agent and are also available upon written request to the Company or the Rights Agent. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;This
Right Certificate, with or without other Right Certificates, upon surrender at the office or offices of the Rights Agent designated for such purpose, may be exchanged for another
Right Certificate or Certificates of like tenor and date evidencing Rights entitling the holder to purchase a like aggregate number of shares of Preferred Stock as the Rights evidenced by the Right
Certificate or Certificates surrendered shall have entitled such holder to purchase. If this Right Certificate shall be exercised in part, the holder shall be entitled to receive upon surrender hereof
another Right Certificate or Certificates for the number of whole Rights not exercised. If this Right Certificate shall be exercised in whole or in part pursuant to Section&nbsp;11(a)(ii)&nbsp;of
the Rights Agreement, the holder shall be entitled to
receive this Right Certificate duly marked to indicate that such exercise has occurred as set forth in the Rights Agreement. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Under
certain circumstances, subject to the provisions of the Rights Agreement, the Board of Directors of the Company at its option may exchange all or any part of the Rights evidenced
by this Certificate for shares of the Company's Common Stock or Preferred Stock at an exchange ratio (subject to adjustment) specified in the Rights Agreement. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Subject
to the provisions of the Rights Agreement, the Rights evidenced by this Certificate may be redeemed by the Board of Directors of the Company at its option at a redemption price
of $0.01 per Right (payable in cash, Common Stock or other consideration deemed appropriate by the Board of Directors). </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The
Company is not obligated to issue fractional shares of stock upon the exercise of any Right or Rights evidenced hereby (other than fractions which are integral multiples of one
ten-thousandth of a share of Preferred Stock, which may, at the election of the Company, be evidenced by depositary receipts). If the Company elects not to issue such fractional shares, in
lieu thereof a cash payment will be made, as provided in the Rights Agreement. </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;No
holder of this Right Certificate, as such, shall be entitled to vote or receive dividends or be deemed for any purpose the holder of shares of Preferred Stock, Common Stock or any
other securities of the Company which may at any time be issuable on the exercise hereof, nor shall anything contained in the Rights Agreement or herein be construed to confer upon the holder hereof,
as such, any of the rights of a shareholder of the Company or any right to vote for the election of directors or upon any matter submitted to shareholders at any meeting thereof, or to give or
withhold consent to any corporate action, or to receive notice of meetings or other actions affecting shareholders (except as provided in the Rights Agreement), or to receive dividends or subscription
rights, or otherwise, until the Right or Rights evidenced by this Right Certificate shall have been exercised as provided in the Rights Agreement. </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;This
Right Certificate shall not be valid or obligatory for any purpose until it shall have been countersigned by an authorized signatory of the Rights Agent. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>2</FONT></P>

<HR NOSHADE>
<P style='page-break-before:always'></p>
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<BR>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;WITNESS
the facsimile signature of the proper officers of the Company as a document under corporate seal. </FONT></P>

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<TD COLSPAN=3><FONT SIZE=2>Attested:</FONT></TD>
<TD WIDTH="8%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD COLSPAN=3><FONT SIZE=2>AVANT IMMUNOTHERAPEUTICS,&nbsp;INC.</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="5%"><FONT SIZE=2><BR>
By:</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="37%"><BR><HR NOSHADE></TD>
<TD WIDTH="8%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="8%"><FONT SIZE=2><BR>
By:</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="37%"><BR><HR NOSHADE></TD>
</TR>
<TR VALIGN="TOP">
<TD COLSPAN=3><FONT SIZE=2>[Secretary or Assistant Secretary]</FONT></TD>
<TD WIDTH="8%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="8%"><FONT SIZE=2>Name:</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="37%"><FONT SIZE=2>&nbsp;</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="5%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="37%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="8%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="8%"><FONT SIZE=2>Title:</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="37%"><FONT SIZE=2>[Chairman, Vice Chairman, President or Vice President]</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD COLSPAN=3><FONT SIZE=2><BR>
Countersigned:</FONT></TD>
<TD WIDTH="8%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="8%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="37%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
</TR>
<TR VALIGN="BOTTOM">
<TD COLSPAN=3><FONT SIZE=2><BR>
EQUISERVE TRUST COMPANY, N.A.</FONT></TD>
<TD WIDTH="8%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="8%" VALIGN="TOP"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%" VALIGN="TOP"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="37%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="5%"><FONT SIZE=2><BR>
By:</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="37%"><BR><HR NOSHADE></TD>
<TD WIDTH="8%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="8%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="37%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="5%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="37%"><FONT SIZE=2>Name:<BR>
Title:</FONT></TD>
<TD WIDTH="8%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="8%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="37%"><FONT SIZE=2>&nbsp;</FONT></TD>
</TR>
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<P ALIGN="CENTER"><FONT SIZE=2>3</FONT></P>

<HR NOSHADE>
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<P ALIGN="CENTER"><FONT SIZE=2><B>[Form of Reverse Side of Right Certificate]</B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>FORM OF ASSIGNMENT<BR>
(To be executed by the registered holder if such<BR>
holder desires to transfer the Right Certificate.)  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;FOR VALUE RECEIVED ____________________ hereby sells, assigns and transfers unto _______________________ (Please print name and address of transferee)
_____________________________ this Right Certificate, together with all right, title and interest therein, and does hereby irrevocably constitute and appoint _________________________ Attorney, to
transfer the within Right Certificate on the books of the within-named Company, with full power of substitution. </FONT></P>

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<TD WIDTH="39%"><FONT SIZE=2>Dated: __________, ____</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="49%"><FONT SIZE=2>&nbsp;</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD COLSPAN=2><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="49%"><HR NOSHADE></TD>
</TR>
<TR VALIGN="TOP">
<TD COLSPAN=2><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="49%"><BR><HR NOSHADE><FONT SIZE=2> Signature</FONT></TD>
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<TD COLSPAN=4><FONT SIZE=2><BR>
Signature Guaranteed: ____________________________</FONT></TD>
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<P ALIGN="CENTER"><FONT SIZE=2><B>CERTIFICATE  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The undersigned hereby certifies by checking the appropriate boxes that: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(1)&nbsp;&nbsp;&nbsp;the
Rights evidenced by this Right Certificate ______ are ______ are not being transferred by or on behalf of a Person who is or was an Acquiring Person or an Affiliate
or Associate of any such Person (as such terms are defined in the Rights Agreement); and </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(2)&nbsp;&nbsp;&nbsp;after
due inquiry and to the best knowledge of the undersigned, the undersigned ___&nbsp;did ___&nbsp;did not directly or indirectly acquire the Rights evidenced by
this Right Certificate from any Person who is, was or became an Acquiring Person or an Affiliate or Associate of any such Person. </FONT></P>

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<TR VALIGN="TOP">
<TD WIDTH="48%"><FONT SIZE=2>Dated: __________, ____</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="48%"><FONT SIZE=2>&nbsp;</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="48%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="48%"><HR NOSHADE></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="48%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="48%"><BR><HR NOSHADE><FONT SIZE=2> Signature</FONT></TD>
</TR>
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<P ALIGN="CENTER"><FONT SIZE=2><B>NOTICE  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The signature to the foregoing Assignment and Certificate must correspond to the name as written upon the face of this Right Certificate in every particular,
without alteration or enlargement or any change whatsoever. </FONT></P>

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<P ALIGN="CENTER"><FONT SIZE=2><B>FORM OF ELECTION TO PURCHASE<BR>
(To be executed if holder desires to<BR>
exercise the Right Certificate.)  </B></FONT></P>

<P><FONT SIZE=2>To
AVANT IMMUNOTHERAPEUTICS,&nbsp;INC.: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The
undersigned hereby irrevocably elects to exercise ______ Rights represented by this Right Certificate to purchase the shares of Preferred Stock issuable upon the exercise of the
Rights (or such other securities of the Company or of any other person which may be issuable upon the exercise of the Rights) and requests that certificates for such shares be issued in the name of: </FONT></P>

<P><FONT SIZE=2>Please
insert social security or other identifying taxpayer number:__________<BR></FONT></P>

<HR NOSHADE>
<BR>
<HR NOSHADE>

<P><FONT SIZE=2><BR>
(Please print name and address) </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;If
such number of Rights shall not be all the Rights evidenced by this Right Certificate or if the Rights are being exercised pursuant to Section&nbsp;11(a)(ii)&nbsp;of the Rights
Agreement, a new Right Certificate for the balance of such Rights shall be registered in the name of and delivered to: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Please
insert social security or other identifying taxpayer number:__________<BR></FONT></P>

<HR NOSHADE>
<BR>
<HR NOSHADE>

<P><FONT SIZE=2><BR>
(Please print name and address) </FONT></P>

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<TD WIDTH="2%"><FONT SIZE=0>&nbsp;</FONT></TD>
<TD WIDTH="39%"><FONT SIZE=2>Dated: __________, ____</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="49%"><FONT SIZE=2>&nbsp;</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD COLSPAN=2><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="49%"><HR NOSHADE></TD>
</TR>
<TR VALIGN="TOP">
<TD COLSPAN=2><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="49%"><BR><HR NOSHADE><FONT SIZE=2> Signature</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD COLSPAN=4><FONT SIZE=2><BR>
Signature Guaranteed: ____________________________</FONT></TD>
</TR>
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<P ALIGN="CENTER"><FONT SIZE=2><B>CERTIFICATE  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The undersigned hereby certifies by checking the appropriate boxes that: </FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(1)&nbsp;&nbsp;&nbsp;the
Rights evidenced by this Right Certificate ____&nbsp;are ____&nbsp;are not being exercised by or on behalf of a Person who is or was an Acquiring Person or an
Affiliate or Associate of any such Person (as such terms are defined in the Rights Agreement); and </FONT></P>


<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;(2)&nbsp;&nbsp;&nbsp;after
due inquiry and to the best knowledge of the undersigned, the undersigned ___&nbsp;did ____&nbsp;did not directly or indirectly acquire the Rights evidenced by
this Right Certificate from any Person who is, was or became an Acquiring Person or an Affiliate or Associate of any such Person. </FONT></P>

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<TR VALIGN="TOP">
<TD WIDTH="48%"><FONT SIZE=2>Dated: __________, ____</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="48%"><FONT SIZE=2>&nbsp;</FONT></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="48%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="48%"><HR NOSHADE></TD>
</TR>
<TR VALIGN="TOP">
<TD WIDTH="48%"><FONT SIZE=2><BR>
&nbsp;</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2><BR>&nbsp;</FONT></TD>
<TD WIDTH="48%"><BR><HR NOSHADE><FONT SIZE=2> Signature</FONT></TD>
</TR>
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<HR NOSHADE>
<P style='page-break-before:always'></p>
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<P ALIGN="CENTER"><FONT SIZE=2><B>NOTICE  </B></FONT></P>

<P><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;The signature to the foregoing Election to Purchase and Certificate must correspond to the name as written upon the face of this Right Certificate in every
particular, without alteration or enlargement or any change whatsoever. </FONT></P>

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<BR>
<P><br><A NAME="04BOS2260_3">QuickLinks</A><br></P><!-- TOC_BEGIN -->
<UL>
<FONT SIZE=2><A HREF="#toc_kg2260_1">Exhibit 4.1</A></FONT><BR>
</UL>
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<DOCUMENT>
<TYPE>EX-99.1
<SEQUENCE>4
<FILENAME>a2146122zex-99_1.htm
<DESCRIPTION>EXHIBIT 99.1
<TEXT>
<HTML>
<HEAD>
</HEAD>
<BODY BGCOLOR="#FFFFFF" LINK=BLUE  VLINK=PURPLE>
<BR>
<FONT SIZE=3 ><A HREF="#04BOS2260_4">QuickLinks</A></FONT>
<font size=3> -- Click here to rapidly navigate through this document</font>
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<P ALIGN="RIGHT"><FONT SIZE=2><A
NAME="ks2260_exhibit_99.1"> </A>
<A NAME="toc_ks2260_1"> </A>
<BR></FONT><FONT SIZE=2><B>Exhibit 99.1    <BR>    </B></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2><B>AVANT Immunotherapeutics,&nbsp;Inc.  </B></FONT></P>

<P><FONT SIZE=2><B>FOR IMMEDIATE RELEASE/November&nbsp;5, 2004  </B></FONT></P>

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<TD WIDTH="32%"><FONT SIZE=2>Una S. Ryan, Ph.D.<BR>
President and CEO<BR>
AVANT Immunotherapeutics, Inc.<BR>
(781) 433-0771</FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="32%"><FONT SIZE=2>Avery W. Catlin<BR>
Chief Financial Officer<BR>
AVANT Immunotherapeutics, Inc.<BR>
(781) 433-0771<BR></FONT> <FONT SIZE=2><I>info@avantimmune.com</I></FONT></TD>
<TD WIDTH="3%"><FONT SIZE=2>&nbsp;</FONT></TD>
<TD WIDTH="32%"><FONT SIZE=2><I>For Media:</I></FONT><FONT SIZE=2><BR>
Joan Kureczka<BR>
Kureczka/Martin Associates<BR>
(415) 821-2413<BR></FONT> <FONT SIZE=2><I>jkureczka@comcast.com</I></FONT></TD>
</TR>
</TABLE>
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<P ALIGN="CENTER"><FONT SIZE=2><B>AVANT Adopts Shareholder Rights Plan to Replace Existing<BR>
Rights Plan Which Expires in November  </B></FONT></P>

<P><FONT SIZE=2><B>NEEDHAM, Massachusetts (November&nbsp;5, 2004):</B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;AVANT Immunotherapeutics,&nbsp;Inc.
(NASDAQ: AVAN) announced today that its Board of Directors has adopted a Shareholder Rights Plan to replace its existing Rights Plan which expires on November&nbsp;10, 2004. Dr.&nbsp;Una Ryan,
AVANT Immunotherapeutics,&nbsp;Inc.'s President and Chief Executive Officer, stated, "The Board believes that a Shareholder Rights Plan enhances its ability to protect shareholder interests and
ensures that shareholders receive fair treatment in the event any coercive takeover attempt of AVANT Immunotherapeutics,&nbsp;Inc. is made in the future. The Plan is intended to provide the Board
with sufficient time to consider any and all alternatives to such an action. By adopting a new Rights Plan to replace its existing one, the Board believes it is protecting the interest of all of its
shareholders." </FONT></P>

<P><FONT SIZE=2>In
connection with the adoption of the Shareholder Rights Plan, the Board of Directors declared a dividend distribution of one preferred stock purchase right for each outstanding share of AVANT
Immunotherapeutics,&nbsp;Inc.'s common stock to shareholders of record as of the close of business on November&nbsp;11, 2004. Initially, these rights will not be exercisable and will trade with
the shares of AVANT Immunotherapeutics,&nbsp;Inc.'s common stock. Under the Shareholder Rights Plan, the rights generally will become exercisable if a person becomes an "acquiring person" by
acquiring 15% or more of the common stock of AVANT Immunotherapeutics,&nbsp;Inc. or if a person commences a tender offer that could result in that person owning 15% or more of the common stock of
AVANT Immunotherapeutics,&nbsp;Inc. If a person becomes an "acquiring person," each holder of a right (other than the acquiring person) would be entitled to purchase, at the then-current
exercise price, such number of shares of preferred stock which are equivalent to shares of AVANT Immunotherapeutics,&nbsp;Inc.'s common stock having a value of twice the exercise price of the right.
If AVANT Immunotherapeutics,&nbsp;Inc. is acquired in a merger or other business combination transaction after any such event, each holder of a right would then be entitled to purchase, at the
then-current exercise price, shares of the acquiring company's common stock having a value of twice the exercise price of the right. </FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>-more-
</FONT></P>

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<TD WIDTH="100%"><FONT SIZE=1><B>119 FOURTH AVENUE&nbsp;&nbsp;&nbsp;&nbsp;NEEDHAM, MA 02194-2725 USA&nbsp;&nbsp;&nbsp;&nbsp;781-433-0771&nbsp;&nbsp;&nbsp;&nbsp;FAX 781-433-0262&nbsp;&nbsp;&nbsp;&nbsp;www.avantimmune.com</B></FONT></TD>
</TR>
</TABLE>
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<A NAME="page_ks2260_1_2"> </A>

<P><FONT SIZE=2>AVANT Immunotherapeutics,&nbsp;Inc. discovers, develops and sells innovative vaccines and therapeutics that harness the human immune system to prevent and
treat disease. The company has developed a broad, well-staged pipeline of vaccines and therapeutics for large, high-value, under-served markets. These include an oral human
rotavirus vaccine, which gained its first marketing approval in Mexico in July&nbsp;2004. Six of AVANT's products are in clinical development, including a treatment to reduce complement-mediated
tissue damage associated with cardiac by-pass surgery, and a novel vaccine for cholesterol management. AVANT has also assembled a technology platform that enables the creation of
rapid-protecting, single-dose, oral vaccines that remain stable without refrigeration. The company is developing applications of this vaccine technology in four areas: biodefense,
travelers' vaccines, global health needs, and human food safety. AVANT's goal is to demonstrate proof-of-concept for its products before leveraging further development through
both traditional pharmaceutical partnerships and collaborations with governmental and other organizations. </FONT></P>

<P><FONT SIZE=2>Additional
information on AVANT Immunotherapeutics,&nbsp;Inc. can be obtained through our site on the World Wide Web: </FONT><FONT SIZE=2><I>http://www.avantimmune.com</I></FONT><FONT SIZE=2>. </FONT></P>


<P><FONT SIZE=2><B><I>&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Safe Harbor Statement Under the Private Securities Litigation Reform Act of
1995:</I></B></FONT><FONT SIZE=2>&nbsp;&nbsp;&nbsp;&nbsp;</FONT><FONT SIZE=2><I>This release includes forward-looking statements which reflect AVANT's current views with respect to future events and financial
performance. These forward-looking statements are based on management's beliefs and assumptions and information currently available. The words "believe", "expect", "anticipate", "intend", "estimate",
"project" and similar expressions which do not relate solely to historical matters identify forward-looking statements. Investors should be cautious in relying on forward-looking statements because
they are subject to a variety of risks, uncertainties, and other factors that could cause actual results to differ materially from those expressed in any such forward-looking statements. These factors
include, but are not limited to: (1)&nbsp;the integration of multiple technologies and programs; (2)&nbsp;the ability to adapt AVANT's vectoring systems to develop new, safe and effective orally
administered vaccines against anthrax and plague or other bioterrorism threats or emerging health care threats; (3)&nbsp;the ability to successfully complete development and commercialization of
TP10, CETi-1, CholeraGarde&reg; (Peru-15), Ty800 and other products; (4)&nbsp;the cost, timing, scope and results of ongoing safety and efficacy trials of TP10,
CETi-1, CholeraGarde&reg; (Peru-15), Ty800 and other preclinical and clinical testing; (5)&nbsp;the ability to successfully complete product research and further
development, including animal, pre-clinical and clinical studies of TP10, CETi-1, CholeraGarde&reg; (Peru-15), Ty800 and other products; (6)&nbsp;the
ability of the Company to manage multiple late stage clinical trials for a variety of product candidates; (7)&nbsp;royalty revenues from product sales of Rotarix&reg;, Megan&reg;Vac
1, Megan&reg;Egg and other future products; (8)&nbsp;changes in existing and potential relationships with corporate collaborators; (9)&nbsp;the availability, cost, delivery and quality of
clinical and commercial grade materials supplied by contract manufacturers; (10)&nbsp;the timing, cost and uncertainty of obtaining regulatory
approvals to use TP10, CETi-1, CholeraGarde&reg; (Peru-15) and Ty800, among other purposes, for adults undergoing cardiac surgery, to raise serum HDL cholesterol levels
and to protect travelers and people in endemic regions from diarrhea causing diseases, respectively; (11)&nbsp;the ability to obtain substantial additional funding; (12)&nbsp;the ability to
develop and commercialize products before competitors; (13)&nbsp;the ability to retain certain members of management; and (14)&nbsp;other factors detailed from time to time in filings with the
Securities and Exchange Commission. We expressly disclaim any responsibility to update forward-looking statements.</I></FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>###
</FONT></P>

<P ALIGN="CENTER"><FONT SIZE=2>2</FONT></P>

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<BR>
<P><br><A NAME="04BOS2260_4">QuickLinks</A><br></P><!-- TOC_BEGIN -->
<UL>
<FONT SIZE=2><A HREF="#toc_ks2260_1">Exhibit 99.1</A></FONT><BR>
</UL>
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