Hemophilia A, Hemophilia B
Conditions
Brief summary
Assess the seroprevalence of neutralizing antibodies (NAb) to AAV in adults with severe hemophilia A (coagulation factor VIII \[FVIII\] \<1%) or moderately severe to severe hemophilia B (coagulation factor IX \[FIX\] ≤2%).
Interventions
OTHERNon-treatment, seroprevalence
Non-treatment study examining the prevalence of preexisting immunity to adeno-associated virus (AAV)
Sponsors
Baxalta now part of Shire
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
MALE
Age
18 Years to 75 Years
Healthy volunteers
No
Inclusion criteria
1. Participant is male between 18 and 75 years old at the time of screening. 2. Established severe hemophilia A (plasma Factor VIII (FVIII) activity \<1%) or B (plasma Factor IX (FIX) activity ≤2%). 3. Provision of signed informed consent form (ICF). 4. Participant is willing and able to comply with the requirements of the protocol.
Exclusion criteria
1. Bleeding disorder(s) other than hemophilia A or B. 2. Personal laboratory evidence of having developed inhibitors to FVIII or FIX protein at any time (≥0.6 Bethesda Units \[BU\] on any single test). 3. Currently receiving systemic immunosuppressive therapy, cytotoxic chemotherapy, immunoglobulin therapy, or monoclonal antibody therapy. 4. Received systemic antiviral and/or interferon therapy within 30 days of blood draw, with the exception of treatment for human immunodeficiency virus (HIV). 5. Currently receiving ribavirin and/or interferon based therapy for active hepatitis C virus (HCV). 6. Received immunoglobulin therapy or plasma infusion within 120 days of the blood draw. 7. Has a known immune deficiency other than HIV. 8. Has lymphocyte or plasma cell malignancies. 9. Participant is a family member or employee of the investigator.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Prevalence of neutralizing antibodies (NAb) - Baseline visit | Baseline visit | Prevalence of NAb to naturally occurring adeno-associated virus (AAV) serotypes |
| Prevalence of neutralizing antibodies (NAb) - Year 1 Visit | Year 1 visit | Prevalence of NAb to naturally occurring adeno-associated virus (AAV) serotypes |
| Prevalence of neutralizing antibodies (NAb) - Year 2 Visit | Year 2 visit | Prevalence of NAb to naturally occurring adeno-associated virus (AAV) serotypes |
| Prevalence of neutralizing antibodies (NAb) - Year 3 Visit | Year 3 visit | Prevalence of NAb to naturally occurring adeno-associated virus (AAV) serotypes |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Prevalence of binding antibodies to AAV, including AAV8 and AAV2 | Baseline visit, Year 1 visit, Year 2 visit, and Year 3 visit | Prevalence of binding antibodies to adeno-associated virus (AAV), including AAV8 and AAV2 |
| T-cell mediated immune response to AAV8 | Baseline visit, Year 1 visit, Year 2 visit, and Year 3 visit | T-cell mediated immune response to AAV8 |
| Prevalence of NAb to AAV including AAV2 and AAV8 | Baseline visit, Year 1 visit, Year 2 visit, and Year 3 visit | Prevalence of neutralizing antibodies (NAb) to adeno-associated virus (AAV) including AAV2 and AAV8 |
Countries
Austria, France, Germany, Italy, Spain, United States
Outcome results
None listed