Pfizer, amid a rethink of its rare disease R&D strategy, has punted (PDF) a pair of orphan drug candidates from its clinical development pipeline in a cull that also narrowed the opportunities open to the near-approval JAK3/TEC inhibitorJAK3/TEC inhibitor ritlecitinib.
Recifercept is the most advanced rare disease candidate to become surplus to requirements in the latest pipeline update. The molecule is designed to bind to fibroblast growth factor isoforms and thereby act as a decoy that reduces FGFR3 signaling. Seeing that FGFR3 mutations drive inhibitory signaling in the rare disease achondroplasia, Pfizer made the condition its focus indication for recifercept development.
The program looked to be on track late last year, when Pfizer began a pilot project to check the feasibility of constructing a concurrent external control for recifercept, but has now hit the skids. The termination of development comes weeks after Pfizer wrapped up a phase 2 trial of the long-term safety and efficacy of recifercept.
Pfizer is kicking the candidate to the curb along with PF-06755347, a recombinant Fc fusion protein that is the product of a licensing agreement the Big Pharma formed with GliknikGliknik in 2013. GliknikGliknik received $15 million from Pfizer when the candidate entered phase 1 four years ago.
Pfizer's discontinuation drive also included ending phase 3 trials for the company's blockbuster COVID-19 pill Paxlovid in standard risk populations and as a prophylactic treatment. The antiviral is already authorized in high risk populations but had flopped in a post-exposure trial.