Study to Test the Safety and How Well Patients With Severe Hemophilia A Respond to Treatment With BAY 2599023 (DTX 201), a Drug Therapy That Delivers a Healthy Version of the Defective Factor VIII Gene Into the Nucleus of Liver Cells Using an Altered, Non-infectious Virus (AAV) as a "Shuttle"
Study Details
- Hemophilia A
- Drug: BAY2599023 (DTX201)
- Males age 18 years or older.
- Confirmed diagnosis of hemophilia A as evidenced by their medical history with plasma FVIII activity levels \< 1% of normal or at screening.
- Have \>150 exposure days (EDs) to FVIII concentrates (recombinant or plasma-derived).
- If on prophylaxis, are required to be willing to stop prophylactic treatment at specified time points throughout the study or If on-demand: should have had \> 4 bleeding events in the last 52 weeks
- \- Agree to use reliable barrier contraception.
- History of allergic reaction to any FVIII product.
- Clinically relevant findings in the physical examination considered critical by the treating physician, including obesity with BMI \> 35 kg/m\*2
- Current evidence of measurable inhibitor against factor VIII, prior history of inhibitors to FVIII protein or clinical history suggestive of inhibitor.
- Evidence of active hepatitis B or C.
- Currently on antiviral therapy for hepatitis B or C.
- Significant underlying liver disease.
- Serological evidence of HIV-1 or HIV-2 with CD4 counts ≤200/mm\*3; HIV+ and stable participants with CD4 count \>200/mm\*3 and undetectable viral load are eligible to enroll.
- Detectable antibodies reactive with AAVhu37capsid.
- Participant with another bleeding disorder that is different from hemophilia A (e.g., von Willebrand disease, hemophilia B).
- Participated in a gene transfer trial within the last 52 weeks or in a clinical trial with an investigational product within the last 12 weeks.
- Known or suspected hypersensitivity or allergic reaction to trial product(s) or related FVIII products or any component of BAY2599023 (DTX201), or a contraindication to prednisolone
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.