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".
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ClinicalTrials.gov Identifier: NCT03588299 |
Recruitment Status :
Active, not recruiting
First Posted : July 17, 2018
Last Update Posted : January 6, 2023
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Condition or disease | Intervention/treatment | Phase |
---|---|---|
Hemophilia A | Drug: BAY2599023 (DTX201) | Phase 1 Phase 2 |
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 11 participants |
Allocation: | N/A |
Intervention Model: | Single Group Assignment |
Masking: | None (Open Label) |
Primary Purpose: | Treatment |
Official Title: | A Phase 1/2 Open-label Safety and Dose-finding Study of BAY2599023 (DTX201), an Adeno-associated Virus (AAV) hu37-mediated Gene Transfer of B-domain Deleted Human Factor VIII, in Adults With Severe Hemophilia A |
Actual Study Start Date : | November 7, 2018 |
Estimated Primary Completion Date : | November 3, 2026 |
Estimated Study Completion Date : | November 30, 2026 |

Arm | Intervention/treatment |
---|---|
Experimental: BAY2599023 / (DTX201)
Adult patients with severe hemophilia A, who have been previously treated with FVIII products
|
Drug: BAY2599023 (DTX201)
Single escalating doses with 4 dose steps; Single intravenous (IV) administration. |
- Number of patients with adverse events (AEs), treatment-emergent adverse events (TEAEs), serious adverse events (SAEs) and AEs/SAEs of special interest [ Time Frame: Up to 5 years ]
- Expression pattern of FVIII activity. [ Time Frame: Up to 5 years ]Determined using both a one-stage assay and chromogenic assay.
- Proportion of patients in the respective dose step, that reached an expression of FVIII above 5% [ Time Frame: At 6 months and 12 months following the IV administration of BAY2599023 ]

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 18 Years and older (Adult, Older Adult) |
Sexes Eligible for Study: | Male |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- 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.
Exclusion Criteria:
- 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

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT03588299
United States, Arkansas | |
Arkansas Children's Hospital | |
Little Rock, Arkansas, United States, 72202-3500 | |
United States, Michigan | |
C.S. Mott Children's Hospital | |
Ann Arbor, Michigan, United States, 48109 | |
United States, Wisconsin | |
University of Wisconsin - Madison | |
Madison, Wisconsin, United States, 53792 | |
Bulgaria | |
SHATHD Spec. Hospi. for Active Treatm. of Haematol. Dis. EAD | |
Sofia, Bulgaria, 1756 | |
France | |
Hopital Necker les enfants malades - Paris | |
Paris, France, 75015 | |
Hôpital Pontchaillou | |
Rennes Cedex, France, 35033 | |
Germany | |
Universitätsklinikum des Saarlandes | |
Homburg, Saarland, Germany, 66421 | |
Vivantes Klinikum im Friedrichshain | |
Berlin, Germany, 10249 | |
Netherlands | |
Academisch Medisch Centrum (AMC) | |
Amsterdam, Netherlands, 1105 AZ | |
Universitair Medisch Centrum Groningen | |
Groningen, Netherlands, 9713 GZ | |
Erasmus Medisch Centrum | |
Rotterdam, Netherlands, 3015 CE | |
University Medical Center Utrecht | |
Utrecht, Netherlands, 3584 CX | |
United Kingdom | |
Manchester Royal Infirmary | |
Manchester, United Kingdom, M13 9WL |
Responsible Party: | Bayer |
ClinicalTrials.gov Identifier: | NCT03588299 |
Other Study ID Numbers: |
19429 2017-000806-39 ( EudraCT Number ) |
First Posted: | July 17, 2018 Key Record Dates |
Last Update Posted: | January 6, 2023 |
Last Verified: | January 2023 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Plan Description: | Availability of this study's data will later be determined according to Bayer's commitment to the EFPIA/PhRMA "Principles for responsible clinical trial data sharing". This pertains to scope, timepoint and process of data access. As such, Bayer commits to sharing upon request from qualified researchers patient-level clinical trial data, study-level clinical trial data, and protocols from clinical trials in patients for medicines and indications approved in the US and EU as necessary for conducting legitimate research. This applies to data on new medicines and indications that have been approved by the EU and US regulatory agencies on or after January 01, 2014. Interested researchers can use www.vivli.org to request access to anonymized patient-level data and supporting documents from clinical studies to conduct research. Information on the Bayer criteria for listing studies and other relevant information is provided in the member section of the portal. |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Severe hemophilia A (<1% FVIII activity) Factor VIII gene therapy |
Hemophilia A Blood Coagulation Disorders, Inherited Blood Coagulation Disorders Hematologic Diseases |
Coagulation Protein Disorders Hemorrhagic Disorders Genetic Diseases, Inborn |