Pfizer Ends Hemophilia Gene Therapy Partnership With Sangamo, Sending Stock Plummeting

Sangamo regains rights to its hemophilia A gene therapy but faces uncertainty after Pfizer's withdrawal despite strong Phase III trial results.

Pfizer has terminated its global collaboration and license agreement with Sangamo Therapeutics for the development of giroctocogene fitelparvovec, a gene therapy for hemophilia A.
Sangamo's stock dropped by over 50% following the announcement, reflecting investor concern about the company's future prospects.
The decision comes despite positive Phase III trial results showing the therapy reduced annualized bleeding rates compared to standard prophylaxis.
Pfizer cited limited patient interest in hemophilia A gene therapies and the high costs of development as reasons for ending the partnership.
Sangamo plans to seek new collaboration opportunities to advance the therapy and continue monitoring trial participants during the transition period.