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Pfizer Terminates Domagrozumab (PF-06252616) Clinical Studies for the Treatment of Duchenne Muscular Dystrophy

Thursday, August 30, 2018 - 8:00am

NEW YORK--(BUSINESS WIRE)--Pfizer Inc. (NYSE: PFE) announced today that it is terminating two
ongoing clinical studies evaluating domagrozumab (PF-06252616) for the
treatment of Duchenne muscular dystrophy (DMD): a Phase 2 safety and
efficacy study (B5161002) and an open-label extension study (B5161004).
The Phase 2 study (B5161002), did not meet its primary efficacy
endpoint, which was to demonstrate a difference in the mean change from
baseline in 4 Stair Climb (in seconds) following one year of treatment
with domagrozumab as compared to placebo in patients with DMD. Further
evaluation of the totality of evidence including secondary endpoints did
not support a significant treatment effect. The decision comes after a
thorough review of data available at the time of the primary analysis,
which evaluated all study participants after one year of treatment, as
well as those participants who were in the trial beyond one year. The
studies were not terminated for safety reasons. Pfizer will continue to
review the data to better understand any insights they may provide, and
will share results with the scientific and patient community.

“We are disappointed by these results and while we are not progressing
with the studies, the data will contribute to a greater understanding of
this disease and we will evaluate the total data set to see if there is
a place for this medicine in muscular diseases,” said Seng Cheng, PhD,
Senior Vice President and Chief Scientific Officer, Pfizer Rare Disease
Research Unit. “We are extremely grateful to all those involved with
this trial, especially the boys who participated, and their families.”

Pfizer is continuing research in DMD and rare neuromuscular diseases,
with the goal of bringing therapies to patients with unmet needs. The
company’s continued partnership with advocacy associations and the
community is critical to finding innovative therapies for these
diseases. Pfizer has one ongoing clinical trial in DMD with a gene
therapy, PF-06939926, which is an investigational, recombinant AAV9
capsid carrying a truncated or shortened version of the human dystrophin
gene (mini-dystrophin) under the control of a human muscle specific

About the Domagrozumab Clinical Studies


The Phase 2 double-blind, placebo-controlled, multicenter clinical trial
investigated the efficacy and safety of domagrozumab, administered in
monthly IV doses, in 121 boys aged 6 to 15 with DMD, regardless of
underlying mutation. It was designed as a two-year, placebo-controlled
study (with the primary analysis after one year); all subjects used
background corticosteroid therapy. The open-label extension study was
designed to evaluate long-term safety and efficacy of domagrozumab.

About Duchenne Muscular Dystrophy

Duchenne muscular dystrophy (DMD) is a rare, serious, debilitating
childhood genetic disease characterized by progressive muscle
degeneration and weakness and significantly shortened life expectancy.
It is the most common form of muscular dystrophy worldwide and primarily
affects boys, with incidence of 1 in every 3500 to 5000 live male births
each year.2,3 Children with DMD typically present with signs
of weakness, including late walking, trouble getting up, and difficulty
running or climbing stairs, usually manifesting in early childhood
between the ages of 1 and 4 years.4 The progressive muscle
degeneration leads to a loss of the ability to walk in the early teenage
years, on average. Weakness of respiratory muscles ultimately leads to
use of mechanical ventilatory support, and weakness in cardiac muscle
involvement results in cardiomyopathy.

Pfizer Rare Disease

Rare disease includes some of the most serious of all illnesses and
impacts millions of patients worldwide,5 representing an
opportunity to apply our knowledge and expertise to help make a
significant impact on addressing unmet medical needs.1 The
Pfizer focus on rare disease builds on more than two decades of
experience, a dedicated research unit focusing on rare disease, and a
global portfolio of multiple medicines within a number of disease areas
of focus, including hematology, neuromuscular, and inherited metabolic

Pfizer Rare Disease combines pioneering science and deep understanding
of how diseases work with insights from innovative strategic
collaborations with academic researchers, patients, and other companies
to deliver transformative treatments and solutions. We innovate every
day leveraging our global footprint to accelerate the development and
delivery of groundbreaking medicines and the hope of cures.

Click here
to learn more about our Rare Disease portfolio and how we empower
patients, engage communities in our clinical development programs, and
support programs that heighten disease awareness.

Working together for a healthier world


At Pfizer, we apply science and our global resources to bring therapies
to people that extend and significantly improve their lives. We strive
to set the standard for quality, safety and value in the discovery,
development and manufacture of health care products. Our global
portfolio includes medicines and vaccines as well as many of the world's
best-known consumer health care products. Every day, Pfizer colleagues
work across developed and emerging markets to advance wellness,
prevention, treatments and cures that challenge the most feared diseases
of our time. Consistent with our responsibility as one of the world's
premier innovative biopharmaceutical companies, we collaborate with
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DISCLOSURE NOTICE: The information contained in this release is as of
August 30, 2018. Pfizer assumes no obligation to update forward-looking
statements contained in this release as the result of new information or
future events or developments.

This release contains forward-looking information about Pfizer’s rare
disease portfolio, including its potential benefits, that involves
substantial risks and uncertainties that could cause actual results to
differ materially from those expressed or implied by such statements.
Risks and uncertainties include, among other things,
uncertainties inherent in research and development, including, the
ability to meet anticipated clinical trial commencement and completion
dates and regulatory submission dates, as well as the possibility of
unfavorable clinical trial results, including unfavorable new clinical
data and additional analyses of existing clinical data; the risk that
clinical trial data are subject to differing interpretations, and, even
when we view data as sufficient to support the safety and/or
effectiveness of a product candidate, regulatory authorities may not
share our views and may require additional data or may deny approval
altogether; whether regulatory authorities will be satisfied with the
design of and results from our clinical studies; whether and when any
new drug applications may be filed in any jurisdictions for any rare
disease product candidates; whether and when regulatory authorities in
any such jurisdictions may approve any such applications, which will
depend on the assessment by such regulatory authority of the
benefit-risk profile suggested by the totality of the efficacy and
safety information submitted, and, if approved, whether such product
candidates will be commercially successful; decisions by regulatory
authorities regarding labeling and other matters that could affect the
availability or commercial potential of any rare disease product
candidates; and competitive developments.

A further description of risks and uncertainties can be found in
Pfizer’s Annual Report on Form 10-K for the fiscal year ended December
31, 2017 and in its subsequent reports on Form 10-Q, including in the
sections thereof captioned “Risk Factors” and “Forward-Looking
Information and Factors That May Affect Future Results”, as well as in
its subsequent reports on Form 8-K, all of which are filed with the U.S.
Securities and Exchange Commission and available at



1 Data on file. Pfizer Inc. New York, NY.

2 National Institutes of Health. National Human Genome
Research Institute. Learning About Duchenne Muscular Dystrophy.
Available on
Accessed August 21, 2018.

3 Mendell JR, Shilling C, Leslie ND, Flanigan KM, al-Dahhak
R, Gastier-Foster J, et al. Evidence-based path to newborn screening for
Duchenne muscular dystrophy. Annals of Neurology.

4 NIH. Duchenne muscular dystrophy.
Accessed August 21, 2018.

5 Pfizer Inc. Rare disease.
Accessed August 9, 2018.


Pfizer Inc.
Media Relations:
Neha Wadhwa, (212)733-2835
[email protected]
Chuck Triano, (212)733-3901
[email protected]