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<SEC-DOCUMENT>0001193125-08-079978.txt : 20080411
<SEC-HEADER>0001193125-08-079978.hdr.sgml : 20080411
<ACCEPTANCE-DATETIME>20080411165723
ACCESSION NUMBER:		0001193125-08-079978
CONFORMED SUBMISSION TYPE:	8-K
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20080407
ITEM INFORMATION:		Entry into a Material Definitive Agreement
ITEM INFORMATION:		Regulation FD Disclosure
ITEM INFORMATION:		Financial Statements and Exhibits
FILED AS OF DATE:		20080411
DATE AS OF CHANGE:		20080411

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			REPLIGEN CORP
		CENTRAL INDEX KEY:			0000730272
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		IRS NUMBER:				042729386
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0331

	FILING VALUES:
		FORM TYPE:		8-K
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	000-14656
		FILM NUMBER:		08752777

	BUSINESS ADDRESS:	
		STREET 1:		41 SEYON STREET
		STREET 2:		BUILDING 1, SUITE 100
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02453
		BUSINESS PHONE:		7814499560

	MAIL ADDRESS:	
		STREET 1:		41 SEYON STREET
		STREET 2:		BUILDING 1, SUITE 100
		CITY:			WALTHAM
		STATE:			MA
		ZIP:			02453
</SEC-HEADER>
<DOCUMENT>
<TYPE>8-K
<SEQUENCE>1
<FILENAME>d8k.htm
<DESCRIPTION>FORM 8-K
<TEXT>
<HTML><HEAD>
<TITLE>Form 8-K</TITLE>
</HEAD>
 <BODY BGCOLOR="WHITE">

 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="4"><B>UNITED STATES </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT
FACE="Times New Roman" SIZE="4"><B>SECURITIES AND EXCHANGE COMMISSION </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="3"><B>Washington, D.C. 20549 </B></FONT></P> <P
STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P><center> <P STYLE="line-height:6px;margin-top:0px;margin-bottom:2px;border-bottom:1pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12px;margin-bottom:0px"
ALIGN="center"><FONT FACE="Times New Roman" SIZE="5"><B>FORM 8-K </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>CURRENT REPORT </B></FONT></P> <P
STYLE="margin-top:6px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>PURSUANT TO SECTION&nbsp;13 OR 15(d) OF THE </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman"
SIZE="2"><B>SECURITIES EXCHANGE ACT OF 1934 </B></FONT></P> <P STYLE="margin-top:6px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>Date of Report (Date of earliest event reported) April&nbsp;7, 2008 </B></FONT></P> <P
STYLE="margin-top:24px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="5"><B>REPLIGEN CORPORATION </B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(Exact name of
registration as specified in charter) </B></FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD WIDTH="34%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="32%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="32%"></TD></TR>
<TR>
<TD VALIGN="bottom" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>Delaware</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>0-14656</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>04-2729386</B></FONT></TD></TR>
<TR>
<TD VALIGN="bottom" ALIGN="center"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(State or other jurisdiction</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT
FACE="Times New Roman" SIZE="1"><B>of incorporation)</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(Commission File Number)</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"> <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>IRS Employer</B></FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px" ALIGN="center"><FONT
FACE="Times New Roman" SIZE="1"><B>Identification No.)</B></FONT></P></TD></TR>
</TABLE> <P STYLE="font-size:24px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD WIDTH="50%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="48%"></TD></TR>
<TR>
<TD VALIGN="bottom" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>41 Seyon Street, Bldg. 1, Suite 100, Waltham, MA</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>02453</B></FONT></TD></TR>
<TR>
<TD VALIGN="bottom" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(Address of principal executive offices)</B></FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(Zip Code)</B></FONT></TD></TR>
</TABLE> <P STYLE="margin-top:24px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2"><B>Registrant&#146;s telephone number, including area code (781)&nbsp;250-0111 </B></FONT></P> <P
STYLE="margin-top:24px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="1"><B>(Former name or former address, if changed since last report.) </B></FONT></P> <P
STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P><center> <P STYLE="line-height:6px;margin-top:0px;margin-bottom:2px;border-bottom:1pt solid #000000;width:21%">&nbsp;</P></center> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT
FACE="Times New Roman" 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 (see General Instruction A.2. below):
</FONT></P> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><FONT FACE="WINGDINGS">&#168;</FONT></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Written communications pursuant to Rule 425 under the Securities Act (17 CFR 230.425) </FONT></TD></TR></TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><FONT FACE="WINGDINGS">&#168;</FONT></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Soliciting material pursuant to Rule 14a-12 under the Exchange Act (17 CFR 240.14a-12) </FONT></TD></TR></TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>

<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><FONT FACE="WINGDINGS">&#168;</FONT></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Pre-commencement communications pursuant to Rule 14d-2(b) under the Exchange Act (17 CFR 240.14d-2(b)) </FONT></TD></TR></TABLE> <P
STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="4%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><FONT FACE="WINGDINGS">&#168;</FONT></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Pre-commencement communications pursuant to Rule 13e-4(c) under the Exchange Act (17 CFR 240.13e-4(c)) </FONT></TD></TR></TABLE> <P
STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P> <P STYLE="line-height:1px;margin-top:0px;margin-bottom:2px;border-bottom:1pt solid #000000">&nbsp;</P>

<p Style='page-break-before:always'>
<HR  SIZE="3" COLOR="#999999" WIDTH="100%" ALIGN="CENTER">


<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="9%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><B>Item&nbsp;1.01.</B></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2"><B><U>Entry into a Material Definitive Agreement</U>. </B></FONT></TD></TR></TABLE> <P
STYLE="margin-top:6px;margin-bottom:0px;padding-bottom:3px;line-Height:95%; vertical-align:top"><FONT FACE="Times New Roman" SIZE="2">On April&nbsp;7, 2008 (the &#147;Effective Date&#148;), Repligen Corporation (&#147;Repligen&#148;) and the
University of Michigan (&#147;Michigan&#148;) entered into a settlement agreement (&#147;Settlement Agreement&#148;) with Bristol-Myers Squibb Company (&#147;Bristol&#148;) relating to the lawsuit against Bristol for infringement of U.S. Patent
No.&nbsp;6,685,941 (&#147;the &#145;941 patent&#148;) based on Bristol&#146;s sale of Orencia<FONT FACE="Times New Roman" SIZE="1"><SUP>&reg;</SUP></FONT>. The Settlement Agreement provides for Bristol to make an initial payment of $5,000,000 and to
pay royalties on the U.S. net sales of Orencia<FONT FACE="Times New Roman" SIZE="1"><SUP>&reg;</SUP></FONT> for any clinical indication at a rate of 1.8% for the first $500,000,000 of annual sales, 2.0% for the next $500,000,000 of annual sales and
4% of U.S. annual sales in excess of $1 billion for each year from January&nbsp;1, 2008 until December&nbsp;31, 2013. The settlement also provides for the grant by Repligen and Michigan to Bristol of an exclusive worldwide license under certain
patent rights of Repligen and Michigan. The settlement serves as the basis for Repligen and Michigan to dismiss the lawsuit against Bristol. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px;padding-bottom:3px;line-Height:95%; vertical-align:top"><FONT FACE="Times New Roman" SIZE="2">In January 2006, Repligen and Michigan filed a complaint in the United States District Court for the Eastern
District of Texas against Bristol alleging infringement of the &#145;941 patent based on its sale of Orencia<FONT FACE="Times New Roman" SIZE="1"><SUP>&reg;</SUP></FONT>. The claims of the &#145;941 patent relate to the use of CTLA4-Ig (Orencia<FONT
FACE="Times New Roman" SIZE="1"><SUP>&reg;</SUP></FONT>) for the treatment of specific auto-immune diseases, including rheumatoid arthritis. The &#145;941 patent is owned by Michigan and the United States Department of the Navy and is exclusively
licensed to Repligen. </FONT></P> <P STYLE="font-size:18px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="9%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><B>Item&nbsp;7.01.</B></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2"><B><U>Regulation FD Disclosure</U>. </B></FONT></TD></TR></TABLE> <P STYLE="margin-top:6px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">On April&nbsp;8, 2008 Repligen
announced in a press release that on April&nbsp;7, 2008, Repligen, Michigan and Bristol executed a Settlement Agreement, which serves as the basis for Repligen and Michigan to dismiss the lawsuit against Bristol. The full text of the press release
issued in connection with the announcement is attached as Exhibit 99.1 to this Current Report on Form 8-K. </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">The information and the exhibit attached hereto
shall not be deemed &#147;filed&#148; for purposes of Section&nbsp;18 of the Securities Exchange Act of 1934 (the &#147;Exchange Act&#148;) or otherwise subject to the liabilities of that section, nor shall it be deemed incorporated by reference in
any filing under the Securities Act of 1933 or the Exchange Act, except as expressly set forth by specific reference in such a filing. </FONT></P> <P STYLE="font-size:18px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE STYLE="BORDER-COLLAPSE:COLLAPSE" BORDER="0" CELLPADDING="0" CELLSPACING="0" WIDTH="100%">
<TR>
<TD WIDTH="9%" VALIGN="top" ALIGN="left"><FONT FACE="Times New Roman" SIZE="2"><B>Item&nbsp;9.01.</B></FONT></TD>
<TD ALIGN="left" VALIGN="top"><FONT FACE="Times New Roman" SIZE="2"><B><U>Financial Statements and Exhibits</U>. </B></FONT></TD></TR></TABLE> <P STYLE="margin-top:6px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">(d) Exhibits </FONT></P>
<P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT FACE="Times New Roman" SIZE="2">99.1 Press Release by Repligen Corporation, April&nbsp;8, 2008. </FONT></P>

<p Style='page-break-before:always'>
<HR  SIZE="3" COLOR="#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">SIGNATURES </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px; text-indent:4%"><FONT
FACE="Times New Roman" SIZE="2">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> <P
STYLE="font-size:18px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0">

<TR>
<TD WIDTH="2%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="44%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="4%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="2%"></TD>
<TD VALIGN="bottom" WIDTH="1%"></TD>
<TD WIDTH="44%"></TD></TR>
<TR>
<TD COLSPAN="3" VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">REPLIGEN CORPORATION</FONT></TD></TR>
<TR>
<TD HEIGHT="16" COLSPAN="3"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD>
<TD HEIGHT="16" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" COLSPAN="3"><FONT FACE="Times New Roman" SIZE="2">Dated: April&nbsp;11, 2008</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">By:</FONT></TD>
<TD VALIGN="bottom" STYLE="BORDER-BOTTOM:1px solid #000000"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top" STYLE="BORDER-BOTTOM:1px solid #000000"><FONT FACE="Times New Roman" SIZE="2">/s/ Walter C. Herlihy</FONT></TD></TR>
<TR>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="bottom"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Walter C. Herlihy</FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px"><FONT FACE="Times New Roman" SIZE="2">President and Chief Executive
Officer</FONT></P></TD></TR>
</TABLE>

<p Style='page-break-before:always'>
<HR  SIZE="3" COLOR="#999999" WIDTH="100%" ALIGN="CENTER">

 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="2">EXHIBIT INDEX </FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD></TD>
<TD VALIGN="bottom" WIDTH="7%"></TD>
<TD WIDTH="90%"></TD></TR>
<TR>
<TD VALIGN="bottom" NOWRAP> <P STYLE="border-bottom:1px solid #000000;width:39pt"><FONT FACE="Times New Roman" SIZE="1"><B>Exhibit&nbsp;No.</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="bottom" NOWRAP> <P STYLE="border-bottom:1px solid #000000;width:25pt"><FONT FACE="Times New Roman" SIZE="1"><B>Exhibit</B></FONT></P></TD></TR>
<TR>
<TD HEIGHT="8"></TD>
<TD HEIGHT="8" COLSPAN="2"></TD></TR>
<TR>
<TD VALIGN="top" NOWRAP><FONT FACE="Times New Roman" SIZE="2">99.1</FONT></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;&nbsp;</FONT></TD>
<TD VALIGN="top"><FONT FACE="Times New Roman" SIZE="2">Press Release, dated April 8, 2008</FONT></TD></TR>
</TABLE> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT SIZE="1">&nbsp;</FONT></P>
</BODY></HTML>
</TEXT>
</DOCUMENT>
<DOCUMENT>
<TYPE>EX-99.1
<SEQUENCE>2
<FILENAME>dex991.htm
<DESCRIPTION>PRESS RELEASE
<TEXT>
<HTML><HEAD>
<TITLE>Press Release</TITLE>
</HEAD>
 <BODY BGCOLOR="WHITE">

 <P STYLE="margin-top:0px;margin-bottom:0px" ALIGN="right"><FONT FACE="Times New Roman" SIZE="2"><B>Exhibit 99.1 </B></FONT></P> <P STYLE="font-size:12px;margin-top:0px;margin-bottom:0px">&nbsp;</P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD WIDTH="50%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="48%"></TD></TR>
<TR>
<TD VALIGN="bottom"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="5"><B><I>Repli</I></B><I>Gen</I></FONT></P> <P STYLE="font-size:24px;margin-top:0px;margin-bottom:0px">&nbsp;</P> <P
STYLE="margin-top:0px;margin-bottom:1px"><FONT FACE="Times New Roman" SIZE="2"><B>FOR IMMEDIATE RELEASE</B></FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Repligen Corporation</FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">41 Seyon Street</FONT></P> <P
STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Building #1, Suite 100</FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Waltham, Massachusetts 02453</FONT></P> <P
STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Telephone: 781-250-0111</FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px"><FONT FACE="Times New Roman" SIZE="2">Telefax: 781-250-0115</FONT></P></TD></TR>
</TABLE> <P STYLE="font-size:6px;margin-top:0px;margin-bottom:0px">&nbsp;</P> <P STYLE="line-height:1px;margin-top:0px;margin-bottom:2px;border-bottom:1pt solid #000000">&nbsp;</P> <P
STYLE="margin-top:24px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>CONTACT: </B></FONT></P>
<TABLE CELLSPACING="0" CELLPADDING="0" WIDTH="100%" BORDER="0" ALIGN="center">

<TR>
<TD WIDTH="50%"></TD>
<TD VALIGN="bottom" WIDTH="2%"></TD>
<TD WIDTH="48%"></TD></TR>
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<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Walter C. Herlihy, Ph.D.</FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">President and Chief Executive
Officer</FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px"><FONT FACE="Times New Roman" SIZE="2">(781) 419-1900</FONT></P></TD>
<TD VALIGN="bottom"><FONT SIZE="1">&nbsp;</FONT></TD>
<TD VALIGN="top"> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Laura Whitehouse</FONT></P> <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Vice President, Market
Development</FONT></P> <P STYLE="margin-top:0px;margin-bottom:1px"><FONT FACE="Times New Roman" SIZE="2">(781) 419-1812</FONT></P></TD></TR>
</TABLE> <P STYLE="margin-top:12px;margin-bottom:0px" ALIGN="center"><FONT FACE="Times New Roman" SIZE="3"><B>Repligen Announces Settlement with Bristol-Myers Squibb in Orencia<FONT FACE="Times New Roman"
SIZE="2"><SUP>&reg;</SUP></FONT> Lawsuit </B></FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px;padding-bottom:3px;line-Height:95%; vertical-align:top"><FONT FACE="Times New Roman" SIZE="2"><B>WALTHAM, MA &#150; April&nbsp;8, 2008</B> &#150;
Repligen Corporation (NASDAQ: RGEN) announced today that it has reached a settlement with Bristol-Myers Squibb Company (NYSE: BMY) in its lawsuit alleging infringement of U.S. Patent No.&nbsp;6,685,941 (&#147;the &#145;941 patent&#148;), based on
Bristol-Myers Squibb&#146;s sale of Orencia<FONT FACE="Times New Roman" SIZE="1"><SUP>&reg;</SUP></FONT> for the treatment of rheumatoid arthritis. The settlement provides for Bristol-Myers Squibb to make an initial payment of $5,000,000 and to pay
royalties on the U.S. net sales of Orencia for any clinical indication at a rate of 1.8% for the first $500,000,000 of annual sales, 2.0% for the next $500,000,000 of annual sales and 4% of U.S. annual sales in excess of $1 billion for each year
from January&nbsp;1, 2008 until December&nbsp;31, 2013. The settlement also provides for the grant by Repligen and co-plaintiff the University of Michigan to Bristol-Myers Squibb of an exclusive worldwide license under certain patent rights of
Repligen and the University of Michigan. The settlement serves as the basis for Repligen and co-plaintiff the University of Michigan to dismiss the lawsuit against Bristol-Myers Squibb. </FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px;padding-bottom:3px;line-Height:95%; vertical-align:top"><FONT FACE="Times New Roman" SIZE="2">&#147;We are very pleased by the settlement of this case which will provide us a substantial new source of
revenue,&#148; stated Walter C. Herlihy, President and Chief Executive Officer of Repligen Corporation. &#147;Based on analysts&#146; estimates of U.S. sales of Orencia<FONT FACE="Times New Roman" SIZE="1"><SUP>&reg;</SUP></FONT>, we expect total
cash receipts from our Protein A business, Orencia<FONT FACE="Times New Roman" SIZE="1"><SUP>&reg;</SUP></FONT> royalties, research and development and other income of greater than $30 million for fiscal year 2009, beginning April&nbsp;1,
2008.&#148; </FONT></P> <P STYLE="margin-top:12px;margin-bottom:0px;padding-bottom:3px;line-Height:95%; vertical-align:top"><FONT FACE="Times New Roman" SIZE="2">In January 2006, Repligen and the University of Michigan filed a complaint in the
United States District Court for the Eastern District of Texas against Bristol-Myers Squibb alleging infringement of the &#145;941 patent based on its sale of Orencia<FONT FACE="Times New Roman" SIZE="1"><SUP>&reg;</SUP></FONT>. The claims of the
&#145;941 patent relate to the use of CTLA4-Ig (Orencia<FONT FACE="Times New Roman" SIZE="1"><SUP>&reg;</SUP></FONT>) for the treatment of specific auto-immune diseases, including rheumatoid arthritis. The &#145;941 patent is owned by the University
of Michigan and the United States Department of the Navy and is exclusively licensed to Repligen. </FONT></P> <P STYLE="margin-top:18px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><B>About Repligen Corporation </B></FONT></P> <P
STYLE="margin-top:6px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2">Repligen Corporation is a biopharmaceutical company focused on the development of novel therapeutics for diseases that affect the central nervous system. In addition, we
are the world&#146;s leading supplier of recombinant Protein A, the sales of which partially fund the advancement of our development pipeline while supporting our financial stability. Repligen&#146;s corporate headquarters are located at 41 Seyon
Street, Building #1, Suite 100, Waltham, MA 02453. Additional information may be requested from <U>www.repligen.com</U>. </FONT></P>

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 <P STYLE="margin-top:0px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="2"><I>Repligen Announces Settlement with Bristol-Myers Squibb in Orencia Lawsuit, April 8, 2008 </I></FONT></P> <P
STYLE="margin-top:12px;margin-bottom:0px"><FONT FACE="Times New Roman" SIZE="1">This press release contains forward-looking statements which are made pursuant to the safe harbor provisions of Section&nbsp;27A of the Securities Act of 1933, as
amended, and Section&nbsp;21E of the Securities Exchange Act of 1934, as amended. The forward-looking statements in this release do not constitute guarantees of future performance. Investors are cautioned that statements in this press release which
are not strictly historical statements, including, without limitation, statements regarding current or future financial performance and position, management&#146;s strategy, plans and objectives for future operations, plans and objectives for
product development, plans and objectives for present and future clinical trials and results of such trials, plans and objectives for regulatory approval, litigation, intellectual property, product development, manufacturing plans and performance
such as the anticipated growth in the monoclonal antibody market and our other target markets and projected growth in product sales, constitute forward-looking statements. Such forward-looking statements are subject to a number of risks and
uncertainties that could cause actual results to differ materially from those anticipated, including, without limitation, risks associated with: the success of current and future collaborative relationships, the market acceptance of our products,
our ability to compete with larger, better financed pharmaceutical and biotechnology companies, new approaches to the treatment of our targeted diseases, our expectation of incurring continued losses, our uncertainty of product revenues and profits,
our ability to generate future revenues, our ability to raise additional capital to continue our drug development programs, the success of our clinical trials, our ability to develop and commercialize products, our ability to obtain required
regulatory approvals, our compliance with all Food and Drug Administration regulations, our ability to obtain, maintain and protect intellectual property rights for our products, the risk of litigation regarding our intellectual property rights, our
limited sales and manufacturing capabilities, our dependence on third-party manufacturers and value added resellers, our ability to hire and retain skilled personnel, our volatile stock price, and other risks detailed in Repligen&#146;s filings with
the Securities and Exchange Commission. Repligen assumes no obligation to update any forward-looking information contained in this press release or with respect to the announcements described herein. </FONT></P>
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