<SEC-DOCUMENT>0001628280-23-021708-index.html : 20230609
<SEC-HEADER>0001628280-23-021708.hdr.sgml : 20230609
<ACCEPTANCE-DATETIME>20230609161231
ACCESSION NUMBER:		0001628280-23-021708
CONFORMED SUBMISSION TYPE:	S-3
PUBLIC DOCUMENT COUNT:		8
FILED AS OF DATE:		20230609
DATE AS OF CHANGE:		20230609

FILER:

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

	FILING VALUES:
		FORM TYPE:		S-3
		SEC ACT:		1933 Act
		SEC FILE NUMBER:	333-272551
		FILM NUMBER:		231005389

	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>S-3
<SEQUENCE>1
<FILENAME>xforforms-3june2023.htm
<DESCRIPTION>S-3
<TEXT>
Document 1 - file: xforforms-3june2023.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-FILING FEES
<SEQUENCE>2
<FILENAME>ex107s-3june2023.htm
<DESCRIPTION>EX-FILING FEES
<TEXT>
Document 2 - file: ex107s-3june2023.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-5.1
<SEQUENCE>3
<FILENAME>ex51legalopinions-3june2023.htm
<DESCRIPTION>EX-5.1
<TEXT>
Document 3 - file: ex51legalopinions-3june2023.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>EX-23.1
<SEQUENCE>4
<FILENAME>ex-231pwcconsentsx3q22023.htm
<DESCRIPTION>EX-23.1
<TEXT>
Document 4 - file: ex-231pwcconsentsx3q22023.htm

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>5
<FILENAME>cooley.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 5 - file: cooley.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>6
<FILENAME>image_0.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 6 - file: image_0.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>7
<FILENAME>image_1a.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 7 - file: image_1a.jpg

</DOCUMENT>
<DOCUMENT>
<TYPE>GRAPHIC
<SEQUENCE>8
<FILENAME>image_5a.jpg
<DESCRIPTION>GRAPHIC
<TEXT>
Document 8 - file: image_5a.jpg

</DOCUMENT>
</SEC-DOCUMENT>