A clinical study in 3 parts with a microdystrophin (called GNT0004), a new gene therapy in boys with Duchenne disease who can still walk. The study will start with finding the proper treatment dose (part 1). After that, a comparative study versus placebo will start to assess the safety and the effectiveness of the proper dose of this therapy (part 2). In the end, a follow up period will continue to investigate the treatment safety and efficacy over longer time (part 3).

Phase 1

Recruiting

• Conditions: Duchenne Muscular Dystrophy; MedDRA version: 20.0Level: PTClassification code: 10013801Term: Duchenne muscular dystrophy Class: 100000004850; Therapeutic area: Diseases [C] - Congenital, Hereditary, and Neonatal Diseases and Abnormalities [C16]

• Registration Number: CTIS2023-505187-11-00
• Lead Sponsor: Genethon

Brief Summary

Not available

Detailed Description

Not available

Study Timeline

• Study Start: 2023-05-10
• Last Update Posted: 22 July 2024

Recruitment & Eligibility

• Status: Recruiting
• Sex: Male
• Target Recruitment: 51

Inclusion Criteria

Ambulant Male, Being included in the GNT-014-MDYF study, 6 to 10 years (inclusive), Body weight =75th percentile of the BMI scale (validated chart in force in country site), Positive gene testing with detailed genotyping confirmation of Duchenne Muscular Dystrophy (DMD), i.e. DMD mutations expected to abolish the production of dystrophin except subjects with any mutations affecting exons 1 through 17

Exclusion Criteria

DMD subjects with any mutations affecting exons 1 through 17 and/or with any mutations affecting exons 29 and 30, Presence of neutralizing antibodies against AAV8, Cardiomyopathy based on physical/cardiological examination and echocardiography with Left Ventricular Ejection Fraction (LVEF) below 55% and/or fractional shortening (SF) below 28%, Any respiratory assistance needed including non-invasive daytime or nocturnal ventilation, Inability to perform the planned respiratory functions tests

Study & Design

• Study Type: Interventional clinical trial of medicinal product
• Study Design: Not specified

Primary Outcome Measures

Name	Time	Method
Main Objective: A phase I/II/III study consisting of 3 parts:<br>- Part 1: To determine the dose of IMP: a safe and tolerable dose with acceptable gene expression, to carry over to part 2.<br>- Part 2: To demonstrate clinical efficacy of IMP vs placebo at 1 year after inclusion. To assess the safety and tolerability of IMP vs placebo at 1 year after inclusion.<br>- Part 3. To assess the safety and tolerability of IMP;Secondary Objective: To assess the biodistribution of IMP, To demonstrate the pharmacodynamic activity of IMP, To assess the immunogenicity of IMP, To compare the efficacy on the disease course after 2 years after inclusion, between patients treated with active IMP at first and patients treated after a delay of one year;Primary end point(s): NSAA: change from baseline at week 52

Secondary Outcome Measures

Name	Time	Method
Secondary end point(s):- Safety and tolerability, measured by the incidence of adverse event (AE) or serious adverse event (SAE) evaluated by changes in laboratory parameters, vital signs and in the physical examination;Secondary end point(s):PK/PD endpoints including vector shedding quantification in blood, urine, saliva, feces;Secondary end point(s):Clinical efficacy endpoints including NSAA, Time to 10 Meters Walk/Run Test (10MWRT), Time to Rise From Floor (RFF), 6-Minutes Walk Test (6MWT)