RecruitingPhase 3Diagnostic testSafety and Effectiveness of Giroctocogene Fitelparvovec or Fidanacogene Elaparvovec in Patients With Hemophilia A or B RespectivelyA study to learn about the long-term safety and efficacy of giroctocogene fitelparvovec or fidanacogene elaparvovec in patients with hemophilia A or hemophilia B respectively, who have received treatment through prior participation in a Pfizer-sponsored clinical trial. Data collection and participant visits will be based on standard of care.