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<ACCEPTANCE-DATETIME>20240618171729
ACCESSION NUMBER:		0001213900-24-053881
CONFORMED SUBMISSION TYPE:	S-4/A
PUBLIC DOCUMENT COUNT:		79
FILED AS OF DATE:		20240618
DATE AS OF CHANGE:		20240618

FILER:

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			ARCA biopharma, Inc.
		CENTRAL INDEX KEY:			0000907654
		STANDARD INDUSTRIAL CLASSIFICATION:	IN VITRO & IN VIVO DIAGNOSTIC SUBSTANCES [2835]
		ORGANIZATION NAME:           	03 Life Sciences
		IRS NUMBER:				363855489
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	FILING VALUES:
		FORM TYPE:		S-4/A
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-279387
		FILM NUMBER:		241053031

	BUSINESS ADDRESS:	
		STREET 1:		10170 CHURCH RANCH WAY
		STREET 2:		SUITE 100
		CITY:			WESTMINSTER
		STATE:			CO
		ZIP:			80021
		BUSINESS PHONE:		7209402200

	MAIL ADDRESS:	
		STREET 1:		10170 CHURCH RANCH WAY
		STREET 2:		SUITE 100
		CITY:			WESTMINSTER
		STATE:			CO
		ZIP:			80021

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

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	HYSEQ INC
		DATE OF NAME CHANGE:	19970610
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<DESCRIPTION>AMENDED AND RESTATED ANTIBODY DISCOVERY AND OPTION AGREEMENT (IL-17), DATED MARCH 28, 2024, BY AND AMONG PARAGON THERAPEUTICS, INC., PARUKA HOLDING LLC AND ORUKA THERAPEUTICS, INC
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