<SEC-DOCUMENT>0001628280-25-040443-index.html : 20250814
<SEC-HEADER>0001628280-25-040443.hdr.sgml : 20250814
<ACCEPTANCE-DATETIME>20250814203139
ACCESSION NUMBER:		0001628280-25-040443
CONFORMED SUBMISSION TYPE:	3
PUBLIC DOCUMENT COUNT:		2
CONFORMED PERIOD OF REPORT:	20250812
FILED AS OF DATE:		20250814
DATE AS OF CHANGE:		20250814

REPORTING-OWNER:	

	OWNER DATA:	
		COMPANY CONFORMED NAME:			Craig Adam R
		CENTRAL INDEX KEY:			0001339498
		ORGANIZATION NAME:           	

	FILING VALUES:
		FORM TYPE:		3
		SEC ACT:		1934 Act
		SEC FILE NUMBER:	001-38295
		FILM NUMBER:		251222039

	MAIL ADDRESS:	
		STREET 1:		C/O X4 PHARMACEUTICALS, INC.
		STREET 2:		61 NORTH BEACON STREET, 4TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02134

ISSUER:		

	COMPANY DATA:	
		COMPANY CONFORMED NAME:			X4 Pharmaceuticals, Inc
		CENTRAL INDEX KEY:			0001501697
		STANDARD INDUSTRIAL CLASSIFICATION:	BIOLOGICAL PRODUCTS (NO DIAGNOSTIC SUBSTANCES) [2836]
		ORGANIZATION NAME:           	03 Life Sciences
		EIN:				273181608
		STATE OF INCORPORATION:			DE
		FISCAL YEAR END:			1231

	BUSINESS ADDRESS:	
		STREET 1:		61 NORTH BEACON STREET
		STREET 2:		4TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02134
		BUSINESS PHONE:		857-529-8300

	MAIL ADDRESS:	
		STREET 1:		61 NORTH BEACON STREET
		STREET 2:		4TH FLOOR
		CITY:			BOSTON
		STATE:			MA
		ZIP:			02134

	FORMER COMPANY:	
		FORMER CONFORMED NAME:	Arsanis, Inc.
		DATE OF NAME CHANGE:	20100920
</SEC-HEADER>
<DOCUMENT>
<TYPE>3
<SEQUENCE>1
<FILENAME>wk-form3_1755217894.xml
<DESCRIPTION>FORM 3
<TEXT>
Document 1 - file: wk-form3_1755217894.html

Document 1 - RAW XML: wk-form3_1755217894.xml

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-24
<SEQUENCE>2
<FILENAME>ex24craigpowerofattorney.htm
<DESCRIPTION>EX-24
<TEXT>
Document 2 - file: ex24craigpowerofattorney.htm

</DOCUMENT>
</SEC-DOCUMENT>