Pfizer : to Discontinue Development Program for PF-07265803 for LMNA-Related Dilated Cardiomyopathy

Decision follows results of interim futility analysis which indicate Phase 3 REALM-DCM trial unlikely to meet primary endpoint

NEW YORK, AUGUST 3, 2022 - Pfizer Inc. (NYSE: PFE) today announced that an interim futility analysis of the global Phase 3 trial, REALM-DCM, designed to evaluate the efficacy and safety of PF-07265803 in patients with symptomatic dilated cardiomyopathy (DCM) due to a mutation of the gene encoding the lamin A/C protein (LMNA), indicated the trial is unlikely to meet its primary endpoint upon completion. Based on these results, the Phase 3 trial and further development of PF-07265803 will be discontinued. This decision is not based on safety concerns.

"This development confirms the complexity of advancing new treatments for rare cardiovascular diseases and the need to further increase knowledge in this space. We thank the patients, families, investigators and members of the advocacy community who contributed to this research," said Chris Boshoff, M.D., Ph.D., Chief Development Officer, Oncology and Rare Disease, Pfizer Global Product Development. "Although this outcome is disappointing, Pfizer remains committed to continuing our work to evolve the treatment paradigm for patients with rare cardiovascular diseases."

Pfizer is communicating with worldwide regulatory authorities, investigators and community groups regarding the discontinuation. Under their investigator's guidance, patients enrolled in the Phase 3 trial will stop study medication and complete any necessary follow-up evaluations. Detailed data from the REALM-DCM study will be presented at future medical meetings to help inform ongoing research.

About REALM-DCM
REALM-DCM (NCT03439514) is a multinational, Phase 3, placebo-controlled study evaluating the efficacy and safety of PF-07265803 in patients with symptomatic LMNA-related DCM. The primary outcome measure is change from baseline in the six-minute walk test at 24 weeks, which is a measure of participant exercise tolerance as an estimate of functional capacity.

About PF-07265803
PF-07265803 (formerly ARRY-371797) is an investigational compound being studied for the treatment of symptomatic DCM due to an LMNA gene mutation. PF-07265803 is a potent and selective, oral, small-molecule inhibitor of the p38α mitogen activated protein kinase pathway, which demonstrated improvement in functional capacity (6-minute walk test; 6MWT) in a 48-week, open-label, Phase 2 study among patients with symptomatic LMNA-related DCM. Pfizer obtained PF-07265803 from Array Biopharma upon acquisition in July 2019.

About Pfizer Rare Disease
Rare disease includes some of the most serious of all illnesses and impacts millions of patients worldwide, representing an opportunity to apply our knowledge and expertise to help make a significant impact on addressing unmet medical needs. 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 rare hematologic, neurologic, cardiac, renal and inherited metabolic disorders.

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.

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.

About Pfizer: Breakthroughs That Change Patients' Lives
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, including innovative medicines and vaccines. 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 health care providers, governments and local communities to support and expand access to reliable, affordable health care around the world. For more than 170 years, we have worked to make a difference for all who rely on us. We routinely post information that may be important to investors on our website at www.Pfizer.com. In addition, to learn more, please visit us on www.Pfizer.com and follow us on Twitter at @Pfizer and @Pfizer New, LinkedIn, YouTube and like us on Facebook at Facebook.com/Pfizer.

Disclosure Notice
The information contained in this release is as of August 3, 2022. 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 their 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 regarding the commercial success of any of Pfizer's rare disease products or product candidates; the uncertainties inherent in research and development, including the ability to meet anticipated clinical endpoints, commencement and/or completion dates for our clinical trials, regulatory submission dates, regulatory approval dates and/or launch dates, as well as the possibility of unfavorable new clinical data and further analyses of existing clinical data; the risk that clinical trial data are subject to differing interpretations and assessments by regulatory authorities; whether regulatory authorities will be satisfied with the design of and results from our clinical studies; whether and when any new or supplemental drug applications may be filed in any jurisdictions for any of Pfizer's rare disease products or product candidates; whether and when regulatory authorities in any jurisdictions may approve any applications for any of Pfizer's rare disease products or product candidates that may be pending or filed for any potential indication, which will depend on myriad factors, including making a determination as to whether the product's benefits outweigh its known risks and determination of the product's efficacy, and, if approved, whether any of Pfizer's rare disease products or product candidates will be commercially successful; decisions by regulatory authorities impacting labeling, manufacturing processes, safety and/or other matters that could affect the availability or commercial potential of any of Pfizer's rare disease products or product candidates; the impact of COVID-19 on our business, operations and financial results; 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, 2021 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 www.sec.gov and www.pfizer.com.

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