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"

NCT03588299 | Active Not Recruiting Phase 1 DMC FDA Drug

• 3 other identifiers: 194292023-505827-29-002017-000806-39
• Study Type: interventional
• Target: 11
• Locations: 6 countries
• Sites: 13

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.

Conditions

Hemophilia A

Keywords

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

Outcome Measures

Primary Outcomes (1)

• Number of patients with adverse events (AEs), treatment-emergent adverse events (TEAEs), serious adverse events (SAEs) and AEs/SAEs of special interest

  Up to 5 years.

Secondary Outcomes (2)

• Expression pattern of FVIII activity.

  Up to 5 years

• Proportion of patients in the respective dose step, that reached an expression of FVIII above 5%

  At 6 months and 12 months following the IV administration of BAY2599023

Study Arms (1)

BAY2599023 / (DTX201)

EXPERIMENTAL

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

Drug: BAY2599023 (DTX201)

Interventions

BAY2599023 (DTX201) DRUG

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

BAY2599023 / (DTX201)

Eligibility Criteria

• Age: 18 Years+
• Sex: male
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• 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.

You may not qualify if:

• 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

Sponsors & Collaborators

• Bayer: lead
• Ultragenix pharmaceutical: collaborator

Study Sites (13)

Arkansas Children's Hospital - Hematology / Oncology

Little Rock, Arkansas, 72202, United States

Location

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

Ann Arbor, Michigan, 48109, United States

Location

UW Health Carbone Cancer Center

Madison, Wisconsin, 53792, United States

Location

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

Sofia, Sofia City Province, 1756, Bulgaria

Location

CHU Rennes - Hopital Pontchaillou

Rennes, Brittany Region, 35033, France

Location

APHP-Hopital Necker Enfants malades

Paris, Île-de-France Region, 75015, France

Location

Universitätsklinikum des Saarlandes

Homburg, Saarland, 66421, Germany

Location

Vivantes Klinikum im Friedrichshain

Berlin, 10249, Germany

Location

Academisch Medisch Centrum (AMC)

Amsterdam, North Holland, 1105 AZ, Netherlands

Location

Erasmus Medisch Centrum

Rotterdam, South Holland, 3015 CE, Netherlands

Location

Universitair Medisch Centrum Groningen

Groningen, 9713 GZ, Netherlands

Location

University Medical Center Utrecht

Utrecht, 3584 CX, Netherlands

Location

Manchester Royal Infirmary

Manchester, Greater Manchester, M13 9WL, United Kingdom

Location

MeSH Terms

Conditions

Hemophilia A

Condition Hierarchy (Ancestors)

Blood Coagulation Disorders, Inherited; Blood Coagulation Disorders; Hematologic Diseases; Hemic and Lymphatic Diseases; Coagulation Protein Disorders; Hemorrhagic Disorders; Genetic Diseases, Inborn; Congenital, Hereditary, and Neonatal Diseases and Abnormalities

Study Design

• Study Type: interventional
• Phase: phase 1
• Allocation: NA
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: SINGLE GROUP
• Sponsor Type: INDUSTRY
• Responsible Party: SPONSOR

Study Record Dates

• First Submitted: July 6, 2018
• First Posted: July 17, 2018
• Study Start: November 7, 2018
• Primary Completion (Estimated): November 3, 2026
• Study Completion (Estimated): November 3, 2026
• Last Updated: April 17, 2026

Record last verified: 2026-04

Data Sharing

• IPD Sharing: Will not share

Locations

FR (2); GB (1); DE (2); NL (4); BU (1); US (3)