<SEC-DOCUMENT>0001144204-17-009016-index.html : 20170214
<SEC-HEADER>0001144204-17-009016.hdr.sgml : 20170214
<ACCEPTANCE-DATETIME>20170214173346
ACCESSION NUMBER:		0001144204-17-009016
CONFORMED SUBMISSION TYPE:	SC 13G/A
PUBLIC DOCUMENT COUNT:		1
FILED AS OF DATE:		20170214
DATE AS OF CHANGE:		20170214

SUBJECT COMPANY:	

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ARCA biopharma, Inc.
		CENTRAL INDEX KEY:			0000907654
		STANDARD INDUSTRIAL CLASSIFICATION:	IN VITRO & IN VIVO DIAGNOSTIC SUBSTANCES [2835]
		IRS NUMBER:				363855489
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	005-51477
		FILM NUMBER:		17610826

	BUSINESS ADDRESS:	
		STREET 1:		11080 CIRCLEPOINT ROAD
		STREET 2:		SUITE 140
		CITY:			WESTMINSTER
		STATE:			CO
		ZIP:			80020
		BUSINESS PHONE:		720-940-2200

	MAIL ADDRESS:	
		STREET 1:		11080 CIRCLEPOINT ROAD
		STREET 2:		SUITE 140
		CITY:			WESTMINSTER
		STATE:			CO
		ZIP:			80020

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	NUVELO INC
		DATE OF NAME CHANGE:	20030203

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	HYSEQ INC
		DATE OF NAME CHANGE:	19970610

FILED BY:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			RA Capital Healthcare Fund LP
		CENTRAL INDEX KEY:			0001315082
		IRS NUMBER:				830406780
		STATE OF INCORPORATION:			DE
		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:		6177782500

	MAIL ADDRESS:	
		STREET 1:		20 PARK PLAZA, SUITE 1200
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02116

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	RA Capital Biotech Fund LP
		DATE OF NAME CHANGE:	20050121
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G/A
<SEQUENCE>1
<FILENAME>v459265_sc13ga.htm
<DESCRIPTION>SC 13G/A
<TEXT>
Document 1 - file: v459265_sc13ga.htm

</DOCUMENT>
</SEC-DOCUMENT>