A Study of FVIII Gene Therapy for Hemophilia A

Inclusion criteria

• Subjects are fully aware of the purpose, nature, methods and possible adverse reactions of the trial and voluntarily sign informed consent.
• Males ≥ 18 years of age.
• Have hemophilia A with ≤2 IU/dL (≤2 %) endogenous FVIII activity levels.
• Have had ≥150 prior exposure days (EDs) to any recombinant and/or plasma-derived FVIII protein products.
• Have had bleeding events and/or infusions with FVIII protein products (including recombination and plasma source) during the last 12 weeks documented in the subjects' medical records.
• Have no prior history of hypersensitivity or anaphylaxis associated with any FVIII or IV immunoglobulin administration.
• Have no FVIII inhibitor. (eg <0.6BU/ml Bethesda Units; or the patient's FVIII inhibitor titer was detected <0.6BU/ml in 2 consecutive times within 1-4 weeks using Bethesda method or Nijmegen method), or no prior medical history of FVIII inhibitor after 150 EDs of FVIII products; no clinical signs or symptoms of decreased response to FVIII products infusion.
• Agree to use a reliable barrier contraception method from the beginning of signing the informed consent to 52 weeks after BBM002 infusion.
• Compliance is good, patients and their families have the will of 'gene therapy' clinical trials.

Exclusion criteria

• Being positive for hepatitis B surface antigen (HBsAg) or hepatitis B virus-DNA (HBV-DNA). Being positive for hepatitis C virus antibody (HCV-Ab) or hepatitis C virus RNA (HCV-RNA).
• Currently on antiviral therapy for hepatitis B or C.
• Patients with coagulation disorders in addition to hemophilia A.
• Use of any other systematic immunosuppressant other than glucocorticoids within 30 days prior to enrollment.
• Patients with vaccination history within 30 days prior to screening.
• Have potential liver diseases, such as previous diagnosis of portal hypertension, splenomegaly, hepatic encephalopathy or liver fibrosis (fibrosis stage ≥ 3); nodules or cysts were found by B ultrasound, or elevated alpha-fetoprotein was detected by laboratory tests. Subjects who are not eligible for the study if the abnormalities are clinically significant by researchers.
• Patients with known planned major surgery schedule during the 52-week study period aren't eligible.
• Have participated in a previous gene therapy research trial before screening, or in a clinical study with an investigational drug within 5 half-life of the investigational product, whichever is longer.
• Have alcohol or drug dependence, or cannot stop drinking throughout the study. 10.Any concurrent clinically significant major disease or condition that the investigator deems unsuitable for participation in the study.