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).

Microdystrophin (GNT0004) Gene Therapy Clinical Trial in Duchenne Muscular Dystrophy A phase I/II/III study with a dose determination part followed by an efficacy and safety evaluation, quadruple blind placebo-controlled part and then by a long term safety follow up part, in ambulant boys. - Microdystrophin (GNT0004) Gene Therapy Clinical Trial in Duchenne Muscular Dystrophy

Status

Active, not recruiting

Phases

Phase 1Phase 2Phase 3

Study type

Interventional

Source

EU CTR

Registry ID

EUCTR2020-002093-27-FR

Enrollment

Registered

2020-06-24

Start date

2020-11-30

Completion date

Unknown

Last updated

2024-10-14

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Duchenne Muscular Dystrophy MedDRA version: 20.0 Level: PT Classification code 10013801 Term: Duchenne muscular dystrophy System Organ Class: 10010331 - Congenital, familial and genetic disorders

Interventions

Product Name: rAAV8-hMD1 Product Code: GNT0004 Pharmaceutical Form: Concentrate for solution for infusion INN or Proposed INN: To be determined Current Sponsor code: GNT0004 Other descriptive name: Ad

Eligibility

Sex/Gender

Male

Inclusion criteria

Inclusion criteria: 1 Male 2 Being included in the GNT-014-MDYF study 3 6 to 10 years (inclusive) 4 Positive gene testing with detailed genotyping confirmation of DMD, ie DMD mutations expected to abolish the production of dystrophin Are the trial subjects under 18? yes Number of subjects for this age range: 51 F.1.2 Adults (18-64 years) no F.1.2.1 Number of subjects for this age range F.1.3 Elderly (>=65 years) no F.1.3.1 Number of subjects for this age range

Exclusion criteria

Exclusion criteria: 1 Presence of neutralizing antibodies against AAV8 2 Cardiomyopathy based on physical/cardiological examination and echocardiography with Left Ventricular Ejection Fraction (LVEF) below 55% and/or fractional shortening (SF) below 28% 3 Any respiratory assistance needed including non-invasive daytime or nocturnal ventilation 4 Inability to perform the planned respiratory functions tests

Design outcomes

Primary

Measure	Time frame
Main Objective: A phase I/II/III study consisting of 3 parts: - Part 1: To determine the dose of IMP: a safe and tolerable dose with acceptable gene expression, to carry over to part 2. - 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. - 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 ;Timepoint(s) of evaluation of this end point: Week 52	—

Measure

Time frame

Main Objective: A phase I/II/III study consisting of 3 parts: - Part 1: To determine the dose of IMP: a safe and tolerable dose with acceptable gene expression, to carry over to part 2. - 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. - 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 ;Timepoint(s) of evaluation of this end point: Week 52

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Secondary

Measure	Time frame
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 - PK/PD endpoints including vector shedding quantification in blood, urine, saliva, feces - Clinical efficacy endpoints including NSAA, Time to 10 Meters Walk/Run Test (10MWRT), Time to Rise From Floor (RFF), 6-Minutes Walk Test (6MWT) ;Timepoint(s) of evaluation of this end point: Throughout the trial	—

Measure

Time frame

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 - PK/PD endpoints including vector shedding quantification in blood, urine, saliva, feces - Clinical efficacy endpoints including NSAA, Time to 10 Meters Walk/Run Test (10MWRT), Time to Rise From Floor (RFF), 6-Minutes Walk Test (6MWT) ;Timepoint(s) of evaluation of this end point: Throughout the trial

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Countries

France, Israel, United Kingdom, United States

Contacts

Public ContactRegulatory Affairs

Genethon

affaires_reglementaires@genethon.fr0033169472917

Outcome results

None listed

Source: EU CTR (via WHO ICTRP) · Data processed: Feb 4, 2026