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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".

The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Know the risks and potential benefits of clinical studies and talk to your health care provider before participating. Read our disclaimer for details. Identifier: NCT03588299
Recruitment Status : Recruiting
First Posted : July 17, 2018
Last Update Posted : May 2, 2022
Ultragenix pharmaceutical
Information provided by (Responsible Party):

Brief Summary:
In this study researchers want to gather more information about safety and effectiveness of BAY 2599023 (DTX201), a drug therapy that delivers the human factor VIII gene into the human body by use of a viral vector to treat the disease. By replacing the defective gene with a healthy copy the human body may produce clotting factor on its own. Hemophilia A is a bleeding disorder in which the human body does not have enough clotting factor VIII, a protein that controls bleeding. Researcher want to find the optimal dose of BAY 2599023 (DTX201) so that the body may produce enough clotting factor on its own.

Condition or disease Intervention/treatment Phase
Hemophilia A Drug: BAY2599023 (DTX201) Phase 1 Phase 2

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Study Type : Interventional  (Clinical Trial)
Estimated Enrollment : 30 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 : May 31, 2027
Estimated Study Completion Date : June 28, 2027

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.

Primary Outcome Measures :
  1. 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 52 weeks ]

Secondary Outcome Measures :
  1. Expression pattern of FVIII activity. [ Time Frame: Up to 5 years ]
    Determined using both a one-stage assay and chromogenic assay.

  2. 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 ]

Information from the National Library of Medicine

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.

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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

Information from the National Library of Medicine

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 identifier (NCT number): NCT03588299

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Contact: Bayer Clinical Trials Contact (+) 1-888-8422937
Contact: For trial location information (Phone Menu Options '3' or '4') (+)1-888-84 22937

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Sponsors and Collaborators
Ultragenix pharmaceutical
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Responsible Party: Bayer Identifier: NCT03588299    
Other Study ID Numbers: 19429
2017-000806-39 ( EudraCT Number )
First Posted: July 17, 2018    Key Record Dates
Last Update Posted: May 2, 2022
Last Verified: April 2022

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Studies a U.S. FDA-regulated Drug Product: Yes
Studies a U.S. FDA-regulated Device Product: No
Keywords provided by Bayer:
Severe hemophilia A (<1% FVIII activity)
Factor VIII gene therapy
Additional relevant MeSH terms:
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Hemophilia A
Blood Coagulation Disorders, Inherited
Blood Coagulation Disorders
Hematologic Diseases
Coagulation Protein Disorders
Hemorrhagic Disorders
Genetic Diseases, Inborn