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"

NCT ID: NCT03588299

Last Updated: 2025-12-22

Study Results

Results pending

The study team has not published outcome measurements, participant flow, or safety data for this trial yet. Check back later for updates.

Basic Information

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Recruitment Status

ACTIVE_NOT_RECRUITING

Clinical Phase

PHASE1/PHASE2

Total Enrollment

11 participants

Study Classification

INTERVENTIONAL

Study Start Date

2018-11-07

Study Completion Date

2026-11-03

Brief Summary

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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.

Detailed Description

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Conditions

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Hemophilia A

Keywords

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Severe hemophilia A (<1% FVIII activity) Factor VIII gene therapy

Study Design

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Allocation Method

NA

Intervention Model

SINGLE_GROUP

Primary Study Purpose

TREATMENT

Blinding Strategy

NONE

Study Groups

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BAY2599023 / (DTX201)

Adult patients with severe hemophilia A, who have been previously treated with FVIII products

Group Type EXPERIMENTAL

BAY2599023 (DTX201)

Intervention Type DRUG

Single escalating doses with 4 dose steps; Single intravenous (IV) administration.

Interventions

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BAY2599023 (DTX201)

Single escalating doses with 4 dose steps; Single intravenous (IV) administration.

Intervention Type DRUG

Eligibility Criteria

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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
Minimum Eligible Age

18 Years

Eligible Sex

MALE

Accepts Healthy Volunteers

No

Sponsors

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Ultragenix pharmaceutical

UNKNOWN

Sponsor Role collaborator

Bayer

INDUSTRY

Sponsor Role lead

Responsible Party

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Responsibility Role SPONSOR

Locations

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Arkansas Children's Hospital - Hematology / Oncology

Little Rock, Arkansas, United States

Site Status

C.S. Mott Children's Hospital - Hematology / Oncology

Ann Arbor, Michigan, United States

Site Status

UW Health Carbone Cancer Center

Madison, Wisconsin, United States

Site Status

SHATHD Spec. Hospi. for Active Treatm. of Haematol. Dis. EAD

Sofia, , Bulgaria

Site Status

APHP-Hopital Necker Enfants malades

Paris, , France

Site Status

CHU Rennes - Hopital Pontchaillou

Rennes, , France

Site Status

Universitätsklinikum des Saarlandes

Homburg, Saarland, Germany

Site Status

Vivantes Klinikum im Friedrichshain

Berlin, , Germany

Site Status

Academisch Medisch Centrum (AMC)

Amsterdam, , Netherlands

Site Status

Universitair Medisch Centrum Groningen

Groningen, , Netherlands

Site Status

Erasmus Medisch Centrum

Rotterdam, , Netherlands

Site Status

University Medical Center Utrecht

Utrecht, , Netherlands

Site Status

Manchester Royal Infirmary

Manchester, Greater Manchester, United Kingdom

Site Status

Countries

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Spain United States Bulgaria France Germany Netherlands United Kingdom

Related Links

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https://clinicaltrials.bayer.com/

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Other Identifiers

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2023-505827-29-00

Identifier Type: OTHER

Identifier Source: secondary_id

2017-000806-39

Identifier Type: EUDRACT_NUMBER

Identifier Source: secondary_id

19429

Identifier Type: -

Identifier Source: org_study_id