During a recent quarterly stakeholder report, Pfizer announced that in March 2022 the U.S. Food and Drug Administration lifted a clinical hold that had been placed on the Phase 3 AFFINE study in November 2021 following the observance of Factor VIII levels greater than 150% in some study participants. Pfizer will keep the voluntary pause in place until all necessary conditions are met, including approval of updated study protocols by regulatory authorities.
Pfizer also reported that the company was recently made aware of an event of below-the-knee deep vein thrombosis in one trial participant with elevated Factor VIII levels. This patient had a history of thrombotic events prior to participation in the study, which is a known risk factor for subsequent events and an exclusion criterion for participation in AFFINE. The case was assessed to understand all potential contributing factors, including missed doses of investigator-prescribed direct oral anti-coagulants. The patient is reported to be doing well. The information was shared with study investigators, health authorities and the independent external Data Monitoring Committee, and Pfizer responded to queries from health authorities.
Pfizer and Sangamo Therapeutics, Inc. asset that they remain committed to the hemophilia community and anticipate resuming dosing in the AFFINE trial in the third quarter of 2022.