<SEC-DOCUMENT>0001493152-19-001946-index.html : 20190214
<SEC-HEADER>0001493152-19-001946.hdr.sgml : 20190214
<ACCEPTANCE-DATETIME>20190214092250
ACCESSION NUMBER:		0001493152-19-001946
CONFORMED SUBMISSION TYPE:	SC 13G/A
PUBLIC DOCUMENT COUNT:		2
FILED AS OF DATE:		20190214
DATE AS OF CHANGE:		20190214

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ARROWHEAD PHARMACEUTICALS, INC.
		CENTRAL INDEX KEY:			0000879407
		STANDARD INDUSTRIAL CLASSIFICATION:	PHARMACEUTICAL PREPARATIONS [2834]
		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:		19601477

	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:	ARROWHEAD RESEARCH CORP
		DATE OF NAME CHANGE:	20040112

	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:			RTW INVESTMENTS, LP
		CENTRAL INDEX KEY:			0001493215
		IRS NUMBER:				000000000
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A

	BUSINESS ADDRESS:	
		STREET 1:		412 WEST 15TH STREET
		STREET 2:		9TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10011
		BUSINESS PHONE:		646-597-6980

	MAIL ADDRESS:	
		STREET 1:		412 WEST 15TH STREET
		STREET 2:		9TH FLOOR
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10011

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	RTW INVESTMENTS, LLC
		DATE OF NAME CHANGE:	20100602
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G/A
<SEQUENCE>1
<FILENAME>sc13ga.htm
<TEXT>
Document 1 - file: sc13ga.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-1
<SEQUENCE>2
<FILENAME>ex1.htm
<TEXT>
Document 2 - file: ex1.htm

</DOCUMENT>
</SEC-DOCUMENT>