A Study of Recombinant AAV2/6 Human Factor 8 Gene Therapy SB-525 (PF-07055480) in Subjects With Severe Hemophilia A

Prior treatment

• Presence of neutralizing antibodies

Other illness

• Current inhibitor, or history of FVIII inhibitor (except for transient low titer inhibitor detected in childhood)
• History of hypersensitivity response to FVIII
• History of Hepatitis B or HIV-1/2 infection
• History of Hepatitis C, unless viral assays in two samples, collected at least 6 months apart, are negative
• Evidence of any bleeding disorder in addition to hemophilia A
• Presence of \> grade 2 liver fibrosis on elastography for subjects with history of treated Hepatitis C or suspicion of chronic liver disease

Lab values

• History of chronic renal disease or creatinine ≥ 1.5 mg/dL

Other

• Markers of hepatic inflammation or overt or occult cirrhosis
• Presence of liver mass on magnetic resonance imaging (MRI), or, positive alpha fetoprotein

• Male ≥18 years of age
• Severe hemophilia A (past evidence of circulating FVIII activity of \< 1% normal)
• Treated or exposed to FVIII concentrates or cryoprecipitate for at least 150 exposure days
• ≥12 bleeding episodes if receiving on-demand therapy over the preceding 12 months
• Agree to use double barrier contraceptive until at least 3 consecutive semen samples are negative for AAV 2/6 after SB-525 infusion