<SEC-DOCUMENT>0001144204-15-010195.txt : 20150218
<SEC-HEADER>0001144204-15-010195.hdr.sgml : 20150216
<ACCEPTANCE-DATETIME>20150217163029
ACCESSION NUMBER:		0001144204-15-010195
CONFORMED SUBMISSION TYPE:	SC 13G/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20150217
DATE AS OF CHANGE:		20150217
GROUP MEMBERS:		PETER KOLCHINSKY
GROUP MEMBERS:		RA CAPITAL HEALTHCARE FUND, L.P.

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ARROWHEAD RESEARCH CORP
		CENTRAL INDEX KEY:			0000879407
		STANDARD INDUSTRIAL CLASSIFICATION:	SERVICES-COMMERCIAL PHYSICAL & BIOLOGICAL RESEARCH [8731]
		IRS NUMBER:				460408024
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			0930

	FILING VALUES:
		FORM TYPE:		SC 13G/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-48710
		FILM NUMBER:		15623147

	BUSINESS ADDRESS:	
		STREET 1:		225 SOUTH LAKE AVENUE
		STREET 2:		SUITE 1050
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91101
		BUSINESS PHONE:		626-304-3400

	MAIL ADDRESS:	
		STREET 1:		225 SOUTH LAKE AVENUE
		STREET 2:		SUITE 1050
		CITY:			PASADENA
		STATE:			CA
		ZIP:			91101

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INTERACTIVE GROUP INC
		DATE OF NAME CHANGE:	20020509

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	INTERACTIVE INC
		DATE OF NAME CHANGE:	19940224

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			RA CAPITAL MANAGEMENT, LLC
		CENTRAL INDEX KEY:			0001346824
		IRS NUMBER:				830406777
		STATE OF INCORPORATION:			MA
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A

	BUSINESS ADDRESS:	
		STREET 1:		20 PARK PLAZA, SUITE 1200
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116
		BUSINESS PHONE:		617-778-2500

	MAIL ADDRESS:	
		STREET 1:		20 PARK PLAZA, SUITE 1200
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G/A
<SEQUENCE>1
<FILENAME>v401879_sc13ga.htm
<DESCRIPTION>SC 13G/A
<TEXT>
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<P STYLE="margin: 0"></P>

<P STYLE="font: bold 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: center">UNITED STATES<BR>
SECURITIES AND EXCHANGE COMMISSION<BR>
Washington, D.C. 20549</P>

<P STYLE="font: bold 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: center">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: center"><B>SCHEDULE 13G</B></P>

<P STYLE="font: bold 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: center">Under the Securities Exchange Act
of 1934</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: center; text-indent: 0in"><B>&nbsp;</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: center; text-indent: 0in"><B>(Amendment No.
3)*</B></P>

<P STYLE="font: bold 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: center">&nbsp;</P>

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse">
<TR STYLE="vertical-align: top">
    <TD STYLE="width: 100%; border-bottom: Black 1pt solid; line-height: 12pt; font-size: 10pt; text-align: center; font-weight: bold"><FONT STYLE="font-size: 10pt">Arrowhead
Research Corporation</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt; font-size: 10pt; text-align: center"><FONT STYLE="font-size: 10pt">(Name of Issuer)</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt; font-size: 10pt; text-align: center">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="border-bottom: Black 1pt solid; line-height: 12pt; font-size: 10pt; text-align: center"><B>&nbsp;Common Stock,
$0.001 par value</B></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt; font-size: 10pt; text-align: center"><FONT STYLE="font-size: 10pt">(Title of Class of Securities)</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt; font-size: 10pt; text-align: center">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="border-bottom: Black 1pt solid; line-height: 12pt; font-size: 10pt; text-align: center"><B>042797209</B></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt; font-size: 10pt; text-align: center"><FONT STYLE="font-size: 10pt">(CUSIP Number)</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt; font-size: 10pt; text-align: center">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="border-bottom: Black 1pt solid; line-height: 12pt; font-size: 10pt; text-align: center"><FONT STYLE="font-size: 10pt"><B>December
    31, 2014</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt; font-size: 10pt; text-align: center"><FONT STYLE="font-size: 10pt">(Date of Event Which Requires
    Filing of this Statement)</FONT></TD></TR>
</TABLE>
<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Check the appropriate box to designate the rule pursuant
to which this Schedule is filed:</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top; text-align: justify">
<TD STYLE="width: 0.25in; text-align: right"><FONT STYLE="font-family: Wingdings">&uml;</FONT></TD><TD STYLE="width: 0.25in"></TD><TD STYLE="text-align: justify">Rule 13d-1(b)</TD>
</TR></TABLE>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top; text-align: justify">
<TD STYLE="width: 0.25in; text-align: right"><FONT STYLE="font-family: Wingdings">x</FONT></TD><TD STYLE="width: 0.25in"></TD><TD STYLE="text-align: justify">Rule 13d-1(c)</TD>
</TR></TABLE>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top; text-align: justify">
<TD STYLE="width: 0.25in; text-align: right"><FONT STYLE="font-family: Wingdings">&uml;</FONT></TD><TD STYLE="width: 0.25in"></TD><TD STYLE="text-align: justify">Rule 13d-1(d)</TD>
</TR></TABLE>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">*The remainder of this cover page shall be filled out for
a reporting person&rsquo;s initial filing on this form with respect to the subject class of securities, and for any subsequent
amendment containing information which would alter the disclosures provided in a prior cover page.</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">The information required in the remainder of this cover
page shall not be deemed to be &ldquo;filed&rdquo; for the purpose of Section 18 of the Securities Exchange Act of 1934 (&ldquo;<B><I>Act</I></B>&rdquo;)
or otherwise subject to the liabilities of that section of the Act but shall be subject to all other provisions of the Act (however,
see the Notes).</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>


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<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse">
<TR STYLE="vertical-align: top">
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">CUSIP No. <B>042797209</B></FONT></TD>
    <TD STYLE="line-height: 12pt; text-align: center"><FONT STYLE="font-size: 10pt"><B>13G</B></FONT></TD>
    <TD STYLE="line-height: 12pt; text-align: left">Page <U> <B>2</B> </U> of <U> <B>7</B> </U> Pages</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">1.</FONT></TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Names of Reporting Persons.</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">I.R.S. Identification Nos. of above persons (entities
    only).</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt"><B>&nbsp;&nbsp;&nbsp;&nbsp;RA Capital Management,
    LLC</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">2. </FONT></TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Check the Appropriate Box if a Member of a Group (See
    Instructions)</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">(a)</FONT></TD>
    <TD COLSPAN="4" STYLE="line-height: 12pt"><FONT STYLE="font: 10pt Wingdings">&uml;</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD COLSPAN="4" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">(b)</FONT></TD>
    <TD COLSPAN="4" STYLE="line-height: 12pt"><FONT STYLE="font: 10pt Wingdings">&uml;</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">3.</FONT></TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">SEC Use Only </FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">4.</FONT></TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt; padding-left: 0pt"><FONT STYLE="font-size: 10pt">Citizenship or Place of Organization&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
    <B>Massachusetts</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR>
    <TD COLSPAN="3" ROWSPAN="10" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Number of</FONT><BR>
    <FONT STYLE="font-size: 10pt">Shares</FONT><BR>
    <FONT STYLE="font-size: 10pt">Beneficially</FONT><BR>
    <FONT STYLE="font-size: 10pt">Owned by</FONT><BR>
    <FONT STYLE="font-size: 10pt">Each&nbsp;Reporting</FONT><BR>
    <FONT STYLE="font-size: 10pt">Person With</FONT></TD>
    <TD STYLE="vertical-align: top; line-height: 12pt"><FONT STYLE="font-size: 10pt">5.</FONT></TD>
    <TD COLSPAN="3" STYLE="vertical-align: top; line-height: 12pt"><FONT STYLE="font-size: 10pt">Sole Voting Power&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
    <B>0 shares</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">6.</FONT></TD>
    <TD COLSPAN="3" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Shared Voting Power&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
    <B>0 shares</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">7.</FONT></TD>
    <TD COLSPAN="3" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Sole Dispositive Power&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
    <B>0 shares</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">8.</FONT></TD>
    <TD COLSPAN="3" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Shared Dispositive Power&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; <B>0
    shares</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">9.</FONT></TD>
    <TD COLSPAN="5"><P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Aggregate Amount Beneficially Owned by Each Reporting
        Person</P>
        <P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0">&nbsp;&nbsp;<B>&nbsp;&nbsp;0
        shares</B></P></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">10.</FONT></TD>
    <TD COLSPAN="5"><P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Check if the Aggregate Amount in Row (9) Excludes&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
        <FONT STYLE="font-family: Wingdings">&uml;</FONT></P>
        <P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Certain Shares (See Instructions)</P></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="vertical-align: top; line-height: 12pt"><FONT STYLE="font-size: 10pt">11.</FONT></TD>
    <TD COLSPAN="5" STYLE="vertical-align: top"><P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Percent of Class Represented by Amount in Row (9)</P>
        <P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0">&nbsp;&nbsp;&nbsp;&nbsp;<B>0%</B></P></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">12.</FONT></TD>
    <TD COLSPAN="5"><P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Type of Reporting Person (See Instructions)</P>
        <P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0">&nbsp;&nbsp;&nbsp;&nbsp;<B>IA</B></P></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR>
    <TD STYLE="width: 5%">&nbsp;</TD>
    <TD STYLE="width: 5%">&nbsp;</TD>
    <TD STYLE="width: 5%">&nbsp;</TD>
    <TD STYLE="width: 5%">&nbsp;</TD>
    <TD STYLE="width: 15%">&nbsp;</TD>
    <TD STYLE="width: 32%">&nbsp;</TD>
    <TD STYLE="width: 33%">&nbsp;</TD></TR>
</TABLE>
<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>&nbsp;</B></P>


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<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>&nbsp;</B></P>

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse">
<TR STYLE="vertical-align: top">
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">CUSIP No. <B>042797209</b></font></TD>
    <TD STYLE="line-height: 12pt; text-align: center"><FONT STYLE="font-size: 10pt"><B>13G</B></FONT></TD>
    <TD STYLE="line-height: 12pt"><P STYLE="margin: 0pt 0">Page <U> <B>3</B> </U> of <U> <B>7</B> </U> Pages</P>


</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">1.</FONT></TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Names of Reporting Persons.</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">I.R.S. Identification Nos. of above persons (entities
    only).</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt">&nbsp;&nbsp;<FONT STYLE="font-size: 10pt"><B>&nbsp;&nbsp;Peter Kolchinsky</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">2. </FONT></TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Check the Appropriate Box if a Member of a Group (See
    Instructions)</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">(a)</FONT></TD>
    <TD COLSPAN="4" STYLE="line-height: 12pt"><FONT STYLE="font: 10pt Wingdings">&uml;</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD COLSPAN="4" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">(b)</FONT></TD>
    <TD COLSPAN="4" STYLE="line-height: 12pt"><FONT STYLE="font: 10pt Wingdings">&uml;</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">3.</FONT></TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">SEC Use Only </FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">4.</FONT></TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Citizenship or Place of Organization&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
    <B>United States</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR>
    <TD COLSPAN="3" ROWSPAN="10" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Number of</FONT><BR>
    <FONT STYLE="font-size: 10pt">Shares</FONT><BR>
    <FONT STYLE="font-size: 10pt">Beneficially</FONT><BR>
    <FONT STYLE="font-size: 10pt">Owned by</FONT><BR>
    <FONT STYLE="font-size: 10pt">Each&nbsp;Reporting</FONT><BR>
    <FONT STYLE="font-size: 10pt">Person With</FONT></TD>
    <TD STYLE="vertical-align: top; line-height: 12pt"><FONT STYLE="font-size: 10pt">5.</FONT></TD>
    <TD COLSPAN="3" STYLE="vertical-align: top; line-height: 12pt"><FONT STYLE="font-size: 10pt">Sole Voting Power&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
    <B>0 shares</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">6.</FONT></TD>
    <TD COLSPAN="3" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Shared Voting Power&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
    <B>0 shares</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">7.</FONT></TD>
    <TD COLSPAN="3" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Sole Dispositive Power&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
    <B>0 shares</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">8.</FONT></TD>
    <TD COLSPAN="3" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Shared Dispositive Power&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>0
    shares</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">9.</FONT></TD>
    <TD COLSPAN="5"><P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Aggregate Amount Beneficially Owned by Each Reporting
        Person</P>
        <P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0">&nbsp;&nbsp;&nbsp;&nbsp;<B>0 shares</B></P></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">10.</FONT></TD>
    <TD COLSPAN="5"><P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Check if the Aggregate Amount in Row (9) Excludes&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
        <FONT STYLE="font-family: Wingdings">&uml;</FONT></P>
        <P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Certain Shares (See Instructions)</P></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">11.</FONT></TD>
    <TD COLSPAN="5"><P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Percent of Class Represented by Amount in Row (9)</P>
        <P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0">&nbsp;&nbsp;&nbsp;&nbsp;<B>0%</B></P></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">12.</FONT></TD>
    <TD COLSPAN="5"><P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Type of Reporting Person (See Instructions)</P>
        <P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0">&nbsp;&nbsp;&nbsp;&nbsp;<B>IN</B></P></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR>
    <TD STYLE="width: 5%">&nbsp;</TD>
    <TD STYLE="width: 5%">&nbsp;</TD>
    <TD STYLE="width: 5%">&nbsp;</TD>
    <TD STYLE="width: 5%">&nbsp;</TD>
    <TD STYLE="width: 15%">&nbsp;</TD>
    <TD STYLE="width: 32%">&nbsp;</TD>
    <TD STYLE="width: 33%">&nbsp;</TD></TR>
</TABLE>
<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>&nbsp;</B></P>


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<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse">
<TR STYLE="vertical-align: top">
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">CUSIP No. <B>042797209</b></FONT></TD>
    <TD STYLE="line-height: 12pt; text-align: center"><FONT STYLE="font-size: 10pt"><B>13G</B></FONT></TD>
    <TD STYLE="line-height: 12pt">Page <U> <B>4</B> </U> of <U> <B>7</B> </U> Pages</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">1.</FONT></TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Names of Reporting Persons.</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">I.R.S. Identification Nos. of above persons (entities
    only).</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt"><B>&nbsp;&nbsp;</b></FONT><FONT STYLE="font-size: 10pt"><B>&nbsp;&nbsp;RA Capital Healthcare Fund, L.P.</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">2. </FONT></TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Check the Appropriate Box if a Member of a Group (See
    Instructions)</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">(a)</FONT></TD>
    <TD COLSPAN="4" STYLE="line-height: 12pt"><FONT STYLE="font: 10pt Wingdings">&uml;</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD COLSPAN="4" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">(b)</FONT></TD>
    <TD COLSPAN="4" STYLE="line-height: 12pt"><FONT STYLE="font: 10pt Wingdings">&uml;</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">3.</FONT></TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">SEC Use Only </FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">4.</FONT></TD>
    <TD COLSPAN="5" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Citizenship or Place of Organization&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
    <B>Delaware</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR>
    <TD COLSPAN="3" ROWSPAN="10" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Number of</FONT><BR>
    <FONT STYLE="font-size: 10pt">Shares</FONT><BR>
    <FONT STYLE="font-size: 10pt">Beneficially</FONT><BR>
    <FONT STYLE="font-size: 10pt">Owned by</FONT><BR>
    <FONT STYLE="font-size: 10pt">Each&nbsp;Reporting</FONT><BR>
    <FONT STYLE="font-size: 10pt">Person With</FONT></TD>
    <TD STYLE="vertical-align: top; line-height: 12pt"><FONT STYLE="font-size: 10pt">5.</FONT></TD>
    <TD COLSPAN="3" STYLE="vertical-align: top; line-height: 12pt"><FONT STYLE="font-size: 10pt">Sole Voting Power&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
    <B>0 shares</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">6.</FONT></TD>
    <TD COLSPAN="3" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Shared Voting Power&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>0
    shares</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">7.</FONT></TD>
    <TD COLSPAN="3" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Sole Dispositive Power&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
    <B>0 shares</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="4" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">8.</FONT></TD>
    <TD COLSPAN="3" STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Shared Dispositive Power&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
    <B>0 shares</B></FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">9.</FONT></TD>
    <TD COLSPAN="5"><P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Aggregate Amount Beneficially Owned by Each Reporting
        Person</P>
        <P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0">&nbsp;&nbsp;&nbsp;&nbsp;<B>0 shares</B>&nbsp;&nbsp;</P></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">10.</FONT></TD>
    <TD COLSPAN="5"><P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Check if the Aggregate Amount in Row (9) Excludes&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
        <FONT STYLE="font-family: Wingdings">&uml;</FONT></P>
        <P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Certain Shares (See Instructions)</P></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">11.</FONT></TD>
    <TD COLSPAN="5"><P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Percent of Class Represented by Amount in Row (9)</P>
        <P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0">&nbsp;&nbsp;&nbsp;&nbsp;<B>0%</B></P></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">12.</FONT></TD>
    <TD COLSPAN="5"><P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Type of Reporting Person (See Instructions)</P>
        <P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0">&nbsp;&nbsp;&nbsp;&nbsp;<B>PN </B></P></TD></TR>
<TR STYLE="vertical-align: top">
    <TD COLSPAN="7" STYLE="border-bottom: Black 1pt solid; line-height: 12pt">&nbsp;</TD></TR>
<TR>
    <TD STYLE="width: 5%">&nbsp;</TD>
    <TD STYLE="width: 5%">&nbsp;</TD>
    <TD STYLE="width: 5%">&nbsp;</TD>
    <TD STYLE="width: 5%">&nbsp;</TD>
    <TD STYLE="width: 15%">&nbsp;</TD>
    <TD STYLE="width: 32%">&nbsp;</TD>
    <TD STYLE="width: 33%">&nbsp;</TD></TR>
</TABLE>
<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>&nbsp;</B></P>


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<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>&nbsp;</B></P>

<P STYLE="font: 10pt/12pt Times New Roman, Times, Serif; margin: 0">CUSIP No. <B>042797209</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>&nbsp;</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>Item 1.</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">(a)&#9;&nbsp;&nbsp;
&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>Name of Issuer:</B> Arrowhead Research Corporation (the &ldquo;Issuer&rdquo;).</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">(b)&#9;&#9;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>Address of the Issuer&rsquo;s Principal Executive
Offices:</B> 225 South Lake Avenue, Suite 1050, Pasadena, CA 91101.</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>&nbsp;</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>Item 2.&#9;</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0in">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0in">(a)&#9;&#9;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>Name of Person Filing: </B>
This joint statement on Schedule 13G is being filed by Peter Kolchinsky, RA Capital Management, LLC (&ldquo;Capital&rdquo;), and
RA Capital Healthcare Fund, L.P. (the &ldquo;Fund&rdquo;). Mr. Kolchinsky, Capital and the Fund are collectively referred to herein
as the &ldquo;Reporting Persons.&rdquo;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0in">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0in">(b)&#9;<B>&#9;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Address of Principal Business
Office:</B> The principal business office of the Reporting Persons is c/o RA Capital Management, LLC, 20 Park Plaza, Suite 1200,
Boston, MA 02116.</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0in">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0in">(c) &#9;&#9;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;<B>Citizenship:</B> Capital is
a Massachusetts limited liability company. The Fund is a Delaware limited partnership. Mr. Kolchinsky is a United States citizen.</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0in">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0in">(d)&#9;<B>&#9;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Title and Class of Securities:
</B>Common stock (&ldquo;Common Stock&rdquo;).</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0in">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0in">(e)&#9;<B>&#9;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;CUSIP Number:</B> 042797209</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>&nbsp;</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>Item 3.&#9;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;If this statement is filed pursuant to &sect;&sect;240.13d-1(b)
or 240.13d-2(b) or (c), check whether the person filing is a:</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Not applicable.</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>&nbsp;</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"></P>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 6pt"><TR STYLE="vertical-align: top; text-align: justify">
<TD STYLE="width: 0"></TD><TD STYLE="width: 0.75in; text-align: left"><B>Item 4.</B></TD><TD STYLE="text-align: justify"><B>Ownership:</B></TD>
</TR></TABLE>



<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Provide the following information regarding the aggregate
number and percentage of the class of securities of the issuer identified in Item 1.</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"></P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 0"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0"></TD><TD STYLE="width: 0.5in">(a)</TD><TD>Amount Beneficially Owned:**</TD></TR></TABLE>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 2.7pt">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 0.75in">RA Capital Management, LLC -  0 shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 0.75in">Peter Kolchinsky - 0 shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 0.75in">RA Capital Healthcare Fund, L.P. - 0
shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 2.7pt">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 0"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0"></TD><TD STYLE="width: 0.5in">(b)</TD><TD>Percent of Class:**</TD></TR></TABLE>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 0.75in">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 0.75in">RA Capital Management, LLC &ndash; 0%</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 0.75in">Peter Kolchinsky &ndash; 0%</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 0.75in">RA Capital Healthcare Fund, L.P. &ndash; 0%</P>



<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;&nbsp;</P>


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<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 2.7pt">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0; margin-right: 0; margin-bottom: 0">CUSIP No. <B>042797209</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 2.7pt"></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 2.7pt"></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 2.7pt"></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-indent: -0.5in">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 0"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0"></TD><TD STYLE="width: 0.5in">(c)</TD><TD>Number of shares as to which such person has:</TD></TR></TABLE>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-indent: -0.5in">&nbsp;&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 2.7pt"></P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 0"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.5in"></TD><TD STYLE="width: 0.25in">(i)</TD><TD>sole power to vote or to direct the vote **</TD></TR></TABLE>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in">RA Capital Management, LLC - 0 shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in">Peter Kolchinsky - 0 shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in">RA Capital Healthcare Fund, L.P. - 0 shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 2.7pt">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 0"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.5in"></TD><TD STYLE="width: 0.25in">(ii)</TD><TD>shared power to vote or to direct the vote**</TD></TR></TABLE>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in">RA Capital Management, LLC &ndash; 0 shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in">Peter Kolchinsky - 0 shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in">RA Capital Healthcare Fund, L.P. - 0
shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 2.7pt">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 0"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.5in"></TD><TD STYLE="width: 0.25in">(iii)</TD><TD>Sole power to dispose or to direct the disposition of**</TD></TR></TABLE>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in">RA Capital Management, LLC - 0 shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in">Peter Kolchinsky - 0 shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in">RA Capital Healthcare Fund, L.P. - 0 shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 2.7pt">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 0"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0.5in"></TD><TD STYLE="width: 0.25in">(iv)</TD><TD>shared power to dispose or to direct the disposition of**</TD></TR></TABLE>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in">RA Capital Management, LLC - 0 shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in">Peter Kolchinsky - 0 shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in">RA Capital Healthcare Fund, L.P. - 0
shares</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 2.7pt">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"></P>

<P STYLE="margin: 0pt 0">** <FONT STYLE="font: 10pt Times New Roman, Times, Serif">&nbsp;Capital serves as investment adviser for
the Fund. Mr. Kolchinsky serves as the manager of Capital.</FONT></P>





<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B></B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"></P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0"></TD><TD STYLE="width: 0.75in"><B>Item 5.</B></TD><TD><B>Ownership of Five Percent or Less of a Class:</B></TD></TR></TABLE>



<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0pt 0">If this statement is being filed to report the fact that
as of the date hereof the Reporting Person has ceased to be the beneficial owner of more than five percent of the class of securities,
check the following <FONT STYLE="font-family: Wingdings">x</FONT>.</P>



<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in; text-indent: -1in"><B>&nbsp;</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in; text-indent: -1in"><B></B></P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0"></TD><TD STYLE="width: 0.75in"><B>Item 6.</B></TD><TD><B>Ownership of More than Five Percent on Behalf of Another Person:</B></TD></TR></TABLE>



<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in; text-indent: -1in"><B>&nbsp;</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 1in; text-indent: -1in"></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Not applicable.</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>&nbsp;</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>Item 7.&#9;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;Identification and Classification of the
Subsidiary Which Acquired the Security Being Reported on By the Parent Holding Company or Control Person:</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Not applicable.</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt">
<TR STYLE="vertical-align: top; text-align: justify">
<TD STYLE="width: 0"></TD><TD STYLE="text-align: left; width: 0.75in"><B>Item 8.</B></TD><TD STYLE="text-align: justify"><B>Identification and Classification of Members of the
Group:</B></TD>
</TR>
</TABLE>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Not applicable.</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>


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<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">CUSIP No. <B>042797209</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>




<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"></P>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top; text-align: justify">
<TD STYLE="width: 0"></TD><TD STYLE="width: 0.75in; text-align: left"><B>Item 9.</B></TD><TD STYLE="text-align: justify"><B>Notice of Dissolution of Group:</B></TD>
</TR></TABLE>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">Not applicable.</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><B>&nbsp;</B></P>

<TABLE CELLPADDING="0" CELLSPACING="0" STYLE="width: 100%; font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0pt; margin-bottom: 0pt"><TR STYLE="vertical-align: top; text-align: justify">
<TD STYLE="width: 0"></TD><TD STYLE="width: 0.75in; text-align: left"><B>Item 10.</B></TD><TD STYLE="text-align: justify"><B>Certification:</B></TD>
</TR></TABLE>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">By signing below I hereby certify that, to the best of my
knowledge and belief, the securities referred to above were not acquired and are not held for the purpose of or with the effect
of changing or influencing the control of the issuer of the securities and were not acquired and are not held in connection with
or as a participant in any transaction having that purpose or effect.</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0"><U>Exhibits</U></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0 0 0 0.5in; text-indent: -0.5in">&nbsp;</P>

<TABLE CELLPADDING="0" CELLSPACING="0" WIDTH="100%" STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin-top: 0; margin-bottom: 0"><TR STYLE="vertical-align: top">
<TD STYLE="width: 0"></TD><TD STYLE="width: 0.5in">1</TD><TD>Joint Filing Agreement by and among the Reporting Persons is incorporated
                                         herein by reference to Exhibit 1 to the Schedule 13G filed by the Reporting Persons with
                                         the Securities and Exchange Commission on November 14<FONT STYLE="text-transform: uppercase">, 2013</FONT>.&nbsp;</TD></TR></TABLE>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: center"><I>&nbsp;</I></P>


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<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: center"><I>&nbsp;</I></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-align: center"><B>SIGNATURE</B></P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in">&nbsp;</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in">After reasonable inquiry and to the
best of my knowledge and belief, I certify that the information set forth in this statement is true, complete and correct.</P>

<P STYLE="font: 10pt/normal Times New Roman, Times, Serif; margin: 0; text-indent: 0.5in">&nbsp;</P>

<TABLE CELLSPACING="0" CELLPADDING="0" STYLE="font: 10pt Times New Roman, Times, Serif; width: 100%; border-collapse: collapse">
<TR STYLE="vertical-align: top">
    <TD STYLE="width: 50%; line-height: 12pt"><FONT STYLE="font-size: 10pt; text-transform: uppercase">&nbsp;</FONT></TD>
    <TD STYLE="width: 50%; line-height: 12pt"><FONT STYLE="font-size: 10pt; text-transform: uppercase">Date: </FONT><FONT STYLE="font-size: 10pt">February
    17, 2015</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">RA CAPITAL MANAGEMENT, LLC</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; line-height: 12pt"><FONT STYLE="font-size: 10pt">By: /s/ Peter Kolchinsky</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Peter Kolchinsky</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Manager</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">PETER KOLCHINSKY</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; line-height: 12pt"><FONT STYLE="font-size: 10pt">/s/ Peter Kolchinsky</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">RA CAPITAL HEALTHCARE FUND, L.P.</FONT></TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt">&nbsp;</TD></TR>
<TR STYLE="vertical-align: top">
    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">By: RA Capital Management, LLC</FONT></TD></TR>
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    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="padding-left: 27pt; line-height: 12pt"><FONT STYLE="font-size: 10pt">General Partner</FONT></TD></TR>
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    <TD STYLE="line-height: 12pt">&nbsp;</TD></TR>
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    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="border-bottom: Black 1pt solid; line-height: 12pt"><FONT STYLE="font-size: 10pt">By: /s/ Peter Kolchinsky</FONT></TD></TR>
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    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Peter Kolchinsky</FONT></TD></TR>
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    <TD STYLE="line-height: 12pt">&nbsp;</TD>
    <TD STYLE="line-height: 12pt"><FONT STYLE="font-size: 10pt">Manager</FONT></TD></TR>
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