Pfizer Scraps Phase 3 Therapy for Rare Cardiomyopathy

Pfizer said it would cease development of its experimental therapy for people with symptomatic dilated cardiomyopathy (DCM) due to a mutation of the gene encoding the lamin A/C protein after an interim futility analysis of the global phase 3 trial showed the trial is unlikely to meet its primary endpoint upon completion.

Photo: Chris Boshoff, chief development officer of oncology and rare disease for Pfizer Global Product Development

Pfizer began developing PF-07265803 following its 2019 acquisition of Array Biopharma for $10.6 billion. The deal, however, was driven by the oncology assets in development.

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.

“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, chief development officer of oncology and rare disease for 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.

Author: Rare Daily Staff