Gene Therapy Study in Severe Hemophilia A Patients With Antibodies Against AAV5
Study Details
- Hemophilia A
- Ignored
- Biological: Valoctocogene Roxaparvovec
- Inclusion Criteria:
- Males ≥ 18 years of age with hemophilia A and residual FVIII levels ≤ 1 IU/dL as evidenced by medical history, at the time of signing the informed consent.
- Detectable pre-existing antibodies against the AAV5 vector capsid as measured by AAV5 total antibody ELISA.
- Subject must have been on prophylactic FVIII replacement therapy for at least 12 months prior to study entry.
- No previous documented history of a detectable FVIII inhibitor, and results from a Bethesda assay or Bethesda assay with Nijmegen modification of less than 0.6 Bethesda Units (BU) (or less than 1.0 BU for laboratories with a historical lower sensitivity cutoff for inhibitor detection of 1.0 BU) on 2 consecutive occasions at least one week apart within the past 12 months (at least one of which should be tested at the central laboratory).
- Sexually active participants must agree to use an acceptable method of effective contraception. Participants must agree to contraception use for at least 12 weeks post-infusion.
- Exclusion Criteria:
- Any evidence of active infection including COVID-19, or any immunosuppressive disorder, except for HIV infection. HIV positive patients who meet all other eligibility criteria may be included if they have a CD4 count > 200/mm3 and an undetectable viral load (unquantifiable viral load as defined as less than the limit of quantification by the testing laboratory's assay is permitted) while receiving an antiretroviral therapy (ART) regimen that does not contain efavirenz or another potentially hepatotoxic ART.
- Evidence of liver dysfunction as assessed by liver tests and most recent, prior FibroScan or liver biopsy showing significant fibrosis of 3 or 4 as rated on a scale of 0-4 on the Batts-Ludwig (Batts 1995) or METAVIR (Bedossa 1996) scoring systems, or an equivalent grade of fibrosis if an alternative scale is used.
- Chronic or active hepatitis B or C as evidenced by testing at screening.
- Active malignancy, except non-melanoma skin cancer, or history of hepatic malignancy.
- Any condition that, in the opinion of the investigator or Sponsor would prevent the patient from fully complying with the requirements of the study (including corticosteroid treatment and/or use of alternative immunosuppressive agents outlined in the protocol) and/or would impact or interfere with evaluation and interpretation of subject safety or efficacy result.
Protocol Summary
This study is looking at how safe it is to switch from emicizumab to Mim8, in people with haemophilia A. Mim8 is a new medicine that is used to prevent bleeding episodes in people with haemophilia A. Mim8 works by replacing the function of the missing clotting factor VIII (FVIII). Mim8 will be injected under the skin using a pen-injector either once every week, once every two weeks or once every month. The participants will be trained in using the pen injector. The participants can choose themselves, in collaboration with the study doctor how often they get Mim8 in this study. When the participant will get their first Mim8 injection depends on their current treatment with emicizumab. The participants will get their first Mim8 injection at Visit 2. Participants will have between 6 and 27 Mim8 injections. The total number of injections participants will have depends on their dosing frequency. The study will last for about 6-12 months. While taking part in this study, there are some restrictions about what medicine participant can use. The study doctor will tell the participants more about this. In case the participants experience bleeds, these can be treated with additional haemostatic medicine as agreed with the study doctor. Female participants cannot take part if they are pregnant, breast-feeding or plan to get pregnant during the study period.