X4 Pharmaceuticals Provides Business and Clinical Development Update

  • Expects to commence the global Phase 3 pivotal trial of mavorixafor
    for the treatment of patients with Warts, Hypogammaglobulinemia,
    Infections and Myelokathexis (WHIM) syndrome in second quarter 2019
    having finalized the protocol based on FDA guidance
  • Receives World Health Organization (WHO) approval for mavorixafor
    as recommended International Non-proprietary Name (INN) for X4P-001

CAMBRIDGE, Mass.–(BUSINESS WIRE)–X4 Pharmaceuticals, Inc. (Nasdaq:XFOR), a clinical-stage
biopharmaceutical company focused on the development of novel
therapeutics for the treatment of rare diseases, today provided a
business and clinical development update.

“This has been a transformative period for X4 with our listing on
Nasdaq, finalization of our Phase 3 clinical protocol in WHIM syndrome
and the recent approval from the WHO for the use of mavorixafor as our
lead candidate name for X4P-001,” said Paula Ragan, Ph.D., President and
Chief Executive Officer of X4 Pharmaceuticals. “We look forward to
advancing our rare disease pipeline throughout the year with plans to
commence a global Phase 3 pivotal trial in WHIM, initiate a Phase 1
trial in severe congenital neutropenia and a Phase 1/2 trial in
Waldenström macroglobulinemia, and to disclose data from our ongoing
Phase 2a trial in clear cell renal cell carcinoma at a medical meeting
later this year.”

Business Update

In March 2019, X4 Pharmaceuticals commenced trading on the Nasdaq
Capital Market under the symbol “XFOR.”

In March 2019, X4 submitted its orphan drug designation request to the
European Medicines Agency (EMA) for mavorixafor for the treatment of
WHIM syndrome. In October 2018, X4 received orphan drug designation from
the FDA for the treatment of WHIM syndrome.

X4 also recently received approval from the World Health Organization
(“WHO”) for mavorixafor as the recommended International Non-proprietary
Name (“INN”) for the company’s lead drug candidate, X4P-001. Mavorixafor
is a first-in-class, oral, allosteric antagonist of the chemokine
receptor CXCR4 with a demonstrated 23-hour half-life and bioavailability
profile that support once-daily oral dosing.

Clinical Development Update

X4 has finalized the clinical trial protocol based on guidance from the
FDA for its randomized, placebo controlled double blinded Phase 3
pivotal trial of mavorixafor for the treatment of patients with WHIM
syndrome and expects to commence the study in the second quarter 2019.
As reviewed with the FDA, the primary endpoint will be the biomarker of
neutrophil count time above threshold (‘TAT’) where the threshold is
defined as 500 cells/uL. The Phase 3 pivotal trial’s secondary
endpoints, including infection rates and wart burden assessments, and
secondary endpoint hierarchy was also reviewed with the FDA. All
enrolled patients ages 12 years and older will receive 400 mg, once
daily, of mavorixafor. The Phase 3 pivotal trial will enroll patients
from the US and from other global sites.

X4 continues to conduct the Phase 2 open label extension study following
the completion of the dose titration portion of the Phase 2 trial for
the treatment of patients with WHIM syndrome in March 2018. Five
patients are continuing to receive mavorixafor in the Phase 2 open-label
extension study and the company plans to provide future updates on the
extension study.

In March 2019, the FDA included WHIM syndrome in a guidance for industry
for Severely Debilitating or Life-Threatening Hematologic Disorders. X4
has made progress in educating key stakeholders regarding the clinical
impact of WHIM syndrome.

X4 is on track to commence a Phase 1 clinical trial of mavorixafor for
the treatment of patients with severe congenital neutropenia (SCN) in
the United States in 2019. The trial is designed to determine the
genetic profile of SCN patients and assess their pharmacodynamic
response to mavorixafor.

X4 also plans to commence a multi-national Phase 1/2 clinical trial of
mavorixafor in combination with ibrutinib for the treatment of patients
with Waldenström macroglobulinemia in 2019. The study population will
focus on patients with WHIM-like mutations in CXCR4 who are known to
respond poorly to standard of care.

X4 has completed enrollment in the open label Phase 2a portion of its
ongoing Phase 1/2 clinical trial of mavorixafor in combination with
axitinib in clear cell renal cell carcinoma (ccRCC) patients. The
Company plans to unveil progression-free survival (PFS) data as part of
an anticipated abstract to be submitted for presentation at a major
medical conference in the second half of 2019.

About X4 Pharmaceuticals
X4 Pharmaceuticals is developing
novel therapeutics designed to improve immune cell trafficking to treat
rare diseases, including primary immunodeficiencies and cancer. X4’s
oral small molecule drug candidates antagonize the CXCR4 pathway, which
plays a central role in immune surveillance. X4’s most advanced product
candidate, mavorixafor (X4P-001), will be commencing a global Phase 3
pivotal trial in patients with WHIM syndrome, a rare genetic, primary
immunodeficiency disease, in the second quarter of 2019 and is currently
also under investigation in a Phase 2a clinical trial in clear cell
renal cell carcinoma. X4 was founded and is led by a team with extensive
product development and commercialization expertise, including several
former members of the Genzyme leadership team, and is located in
Cambridge, Massachusetts. For more information, visit www.x4pharma.com.

Forward-Looking Statements
This press release contains
forward-looking statements that involve substantial risks and
uncertainties. All statements, other than statement of historical facts,
included in this press release regarding our strategy, future
operations, and plans are forward-looking statements. Examples of such
statements include, but are not limited to, statements relating to plans
for, or progress, scope, cost, duration or results or timing for the
initiation, completion or availability of results of development of
mavorixafor (X4P-001) or any of our other product candidates or
programs, including regarding the Phase 3 clinical trial of mavorixafor
for the treatment of patients with WHIM syndrome, the target
indication(s) for development, the size, design, population, location,
conduct, objective, duration or endpoints of any clinical trial, or the
timing for initiation or completion of or reporting of results from any
clinical trial, the potential benefits of mavorixafor, or any other
product candidate or program or the commercial opportunity in any target
indication; or the potential benefits of orphan drug designation. Actual
results or events could differ materially from the plans, intentions,
expectations and projections disclosed in the forward-looking
statements. Various important factors could cause actual results or
events to differ materially from the forward-looking statements that X4
makes, including, but not limited to, the risk that trials and studies
may be delayed and may not have satisfactory outcomes, potential adverse
effects arising from the testing or use of mavorixafor or other product
candidates, the risk that costs required to develop mavorixafor or other
product candidates or to expand our operations will be higher than
anticipated and other risks described in the “Risk Factors” section of
the Registration Statement on Form S-4 filed by X4 Pharmaceuticals with
the SEC and declared effective by the SEC on February 14, 2019. X4 does
not assume any obligation to update any forward-looking statements,
except as required by law.


Stephanie Carrington
Westwicke, an ICR
[email protected]

Darcie Robinson
Westwicke, an ICR company
[email protected]

Leave a Reply

Your email address will not be published. Required fields are marked *

This site uses Akismet to reduce spam. Learn how your comment data is processed.