FDA Clinical Hold on Pfizer Hemophilia A Trial

FDA placed an 11/3 clinical hold on Pfizer’s Phase 3 trial evaluating giroctocogene fitelparvovec for hemophilia A that was paused by the company following the observation of factor VIII (FVIII) levels greater than 150% in some study participants. FDA indicated a future communication would contain more information on its position.

Pfizer says it paused the study to implement a protocol change to provide clinical management guidance for elevated FVIII levels.

No thrombotic events have been seen in any patient treated with giroctocogene fitelparvovec, Pfizer says, and no adverse events thought to be associated with elevated FVIII levels have been observed.

The company says it is committed to resuming patient dosing in the Phase 3 program and believes the gene therapy, if approved, “could represent an important treatment option for patients with hemophilia A.”