0001628280-21-013615.txt : 20210806 0001628280-21-013615.hdr.sgml : 20210806 20210707162019 ACCESSION NUMBER: 0001628280-21-013615 CONFORMED SUBMISSION TYPE: CORRESP PUBLIC DOCUMENT COUNT: 3 FILED AS OF DATE: 20210707 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: CORRESP 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 CORRESP 1 filename1.htm Document

X4 Pharmaceuticals, Inc.
61 North Beacon Street, 4th Floor
Boston, MA 02134

July 7, 2021

Via Edgar
United States Securities and Exchange Commission
Division of Corporation Finance
100 F Street, N.E.
Washington, D.C. 20549
Attn:    Jeffrey Gabor

RE:    X4 Pharmaceuticals, Inc.
    Registration Statement on Form S-3
    File No. 333-257422

    Acceleration Request
        Requested Date:    July 9, 2021
        Requested Time:    4:00 p.m. Eastern Time

Ladies and Gentlemen:
Pursuant to Rule 461 under the Securities Exchange Act of 1933, as amended, the undersigned registrant hereby requests that the Securities and Exchange Commission take appropriate action to cause the above-referenced Registration Statement on Form S-3 (File No. 333-257422) (the “Registration Statement”) to become effective at 4:00 p.m. Eastern Time on Friday, July 9, 2021, or as soon thereafter as is practicable.
Once the Registration Statement has been declared effective, please orally confirm that event with Daniel I. Goldberg of Cooley LLP, counsel to the registrant, at (212) 479-6722.

[Signature page follows]

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Sincerely,
X4 Pharmaceuticals, Inc.


By: __    /s/Adam S. Mostafa        
    Adam S. Mostafa
Chief Financial Officer


cc:    Paula Ragan, Ph.D., Chief Executive Officer, X4 Pharmaceuticals, Inc.    
    Derek Meisner, General Counsel, X4 Pharmaceuticals, Inc.
Daniel I. Goldberg, Cooley LLP
Courtney T. Thorne, Cooley LLP


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