<SEC-DOCUMENT>0001387131-21-001964-index.html : 20210210
<SEC-HEADER>0001387131-21-001964.hdr.sgml : 20210210
<ACCEPTANCE-DATETIME>20210210103014
ACCESSION NUMBER:		0001387131-21-001964
CONFORMED SUBMISSION TYPE:	SC 13G/A
PUBLIC DOCUMENT COUNT:		2
FILED AS OF DATE:		20210210
DATE AS OF CHANGE:		20210210
GROUP MEMBERS:		ALTIUM GROWTH FUND, LP
GROUP MEMBERS:		ALTIUM GROWTH GP, LLC

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:		21609896

	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:			Altium Capital Management LP
		CENTRAL INDEX KEY:			0001746382
		IRS NUMBER:				822066653
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		SC 13G/A

	BUSINESS ADDRESS:	
		STREET 1:		152 W 57 ST FL20
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10019
		BUSINESS PHONE:		2124842711

	MAIL ADDRESS:	
		STREET 1:		152 W 57 ST FL20
		CITY:			NEW YORK
		STATE:			NY
		ZIP:			10019
</SEC-HEADER>
<DOCUMENT>
<TYPE>SC 13G/A
<SEQUENCE>1
<FILENAME>abio-sc13ga_123120.htm
<DESCRIPTION>AMENDMENT TO FORM SC 13G
<TEXT>
Document 1 - file: abio-sc13ga_123120.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-1
<SEQUENCE>2
<FILENAME>ex-1.htm
<DESCRIPTION>JOINT ACQUISITION STATEMENT
<TEXT>
Document 2 - file: ex-1.htm

</DOCUMENT>
</SEC-DOCUMENT>