Genethon newsletter – 2026 Issue Number 1
PARIS, FRANCE (January 26, 2026) – Genethon, a unique non-profit gene therapy R&D organization founded by the French Muscular Dystrophy Association (AFM-Telethon), began the new year with an R&D licensing deal for its gene therapy approach to Pompe disease and continues pivotal clinical trials of its best-in-class low dose micro-dystrophin gene therapy (GNT0004) for Duchenne muscular dystrophy (DMD). Read about these and other advances in Genethon’s latest Newsletter.
CEO Commentary
Genethon Signs Another R&D Licensing Deal; Looks Forward to Its Own Late-Stage Clinical Successes
The year 2026 begins for Genethon with the announcement of the signing of a license agreement with AskBio, the gene therapy subsidiary of Bayer AG.
The agreement is for a proprietary technology developed by Genethon and integrated into AskBio’s drug candidate, AB-1009, for the treatment of Pompe disease. In early January, AskBio announced IND acceptance from the FDA to begin clinical trials.
Pompe disease is very severe and debilitating, and represents a medical need for many patients. We are very pleased with this agreement, and Genethon is once again faithful to its mission to contribute to therapeutic solutions for rare diseases through R&D of excellence.
This will be a rich year for Genethon with the continuation of our pivotal clinical trial for GNT0004, low dose gene therapy for Duchenne Muscular Dystrophy, for which enrollment continues in Europe and the UK. If the pivotal phase results replicate those observed during dose escalation, GNT0004 could well establish itself as best-in-class therapy for DMD patient.
We will also continue to develop our gene therapy products for Limb Girdle Muscular Dystrophies (LGMDR9, LGMDR5 and LGMDR1) and for Crigler Najjar’s disease, to mention only the most advanced. These developments will be made while expanding our pipeline of products at the discovery stage, continuing our cutting-edge research on new vectors and new gene therapy modalities, and aiming to reduce the cost of manufacturing.
This year, which is our 36th, we will continue with dedication to our mission of bringing treatments for these rare genetic diseases considered incurable, and to accomplish for patients what is considered impossible.
Product Development
Genethon’s Phase 3 Trial in Europe Underway to Evaluate Its Low Dose Micro-Dystrophin for Duchenne Muscular Dystrophy
Genethon has begun treating Duchenne muscular dystrophy (DMD) patients in France and the UK in the pivotal trial portion of an all-in-one Phase 1/2/3 study of its low dose micro-dystrophin gene therapy, GNT0004.
The Phase 3 double blind trial will enroll a total of 72 boys ages 6 to 10 with DMD who have retained their walking ability. Regulatory authorization for the trial was based on results of Phase 1/2 studies showing excellent tolerance of GNT0004 as well as striking 2 year long-term efficacy in terms of creatine phosphokinase reduction, a key marker of muscle damage which stably decreased by 70%, in terms of motor function which was stabilized or increased, in addition to microdystrophin expression.
Genethon CEO Frederic Revah said, “One of the strengths of our product is the dose selected for the pivotal phase, which is lower than those used for all other gene therapies for DMD. We are determined to bring GNT0004 to market for young patients and their families who are waiting for a therapeutic solution.”
Read an October 10, 2025 interview with Dr. Revah in Endpoints News. Subscription required or sign-up to read the article for free.
Clinical Trial Data Supports Feasibility of Imlifidase as Pre-Treatment in Gene Therapy for Crigler–Najjar Syndrome Patients Immune to AAV Vector
It is estimated that one in three people are naturally immune to AAV vectors, excluding a large number of patients from the possibility of benefiting from gene therapy.
In an attempt to counter patients’ AAV immunity, Genethon has partnered with Hansa Biopharma to conduct a clinical trial in which Crigler-Najjar syndrome patients immune to AAV vectors are treated with Hansa’s imlifidase, a unique antibody cleaving enzyme, before receiving Genethon’s GNT0003 AAV gene therapy for the rare liver disease.
Findings from the first patient treated in the study demonstrated the feasibility and efficacy of using imlifidase as a pre-treatment for an AAV immune patient receiving GNT0003. Imlifidase successfully “cut” the patient’s antibodies to AAVs and enabled treatment with no severe side effects.
“It’s incredible to have had the chance to witness the clinical translation of this project, which I saw come to life in our laboratory,” said Giuseppe Ronzitti, Head of the Immunology and Liver Disease Laboratory and Director of Scientific Forecasting at Genethon. “The preliminary data we’ve obtained indicate that we still have a lot to learn about the immune response to AAV vectors, but the solution is potentially there.”
Read the October 10, 2025 coverage of the study in Endpoints News. Subscription required or sign up to read article for free.
Genethon Signs Licensing Agreement with AskBio for Development of an Investigational Gene Therapy for Pompe Disease
Genethon has entered into an exclusive, worldwide licensing agreement with AskBio, a gene therapy company wholly owned and independently operated as a subsidiary of Bayer AG, for the use of a patented component of AB-1009 for the treatment of Pompe disease. AskBio anticipates recruiting its first patient in early 2026.
Pompe disease is a rare genetic disorder caused by a deficiency in the GAA enzyme, leading to glycogen accumulation in cells, particularly in muscle tissue.
The Immunology and Liver Diseases team at Genethon, led by Giuseppe Ronzitti, developed and demonstrated the preclinical efficacy of a gene therapy approach using a transgene encoding a truncated form of GAA. This component of AB-1009, protected by patents held by Genethon and other French institutions, is now licensed to AskBio for the development of a gene therapy product to treat Pompe disease. Read the Press Release
Scientific Publications
Genethon Scientists Explore Lysosomal Damage in Duchenne Muscular Dystrophy Patients and Identify a Combination Treatment for Gene Therap
Genethon’s Progressive Muscular Dystrophies Research Team, led by Isabelle Richard, Ph.D., along with researcher Abbass Jaber, Ph.D., under the supervision of David Israeli, Ph.D., has discovered that lysosomal alterations in the muscle fibers of Duchenne muscular dystrophy (DMD) patients play a critical role in the disease.
The research, titled “Lysosomal damage is a therapeutic target in Duchenne Muscular dystrophy,” was published in Science Advances October 22, 2025. The scientists suggested that targeting the lysosomal damage with trehalose, a lysosome-protective sugar, may be an effective complimentary treatment to current DMD gene therapies.
The authors observed their study reveals a “previously underappreciated and critical role for lysosomal damage in the pathophysiology of DMD.” They concluded, “Our proof of concept that combining lysosomal repair strategies with μDys gene therapy improves outcomes, paves the way for novel combinatorial treatments for DMD.”
Genethon in the News
CEO Frederic Revah discusses Genethon’s global leadership in development of gene therapies for rare diseases in articles published by Pharma Boardroom and Genetic Engineering & Biotechnology News
Genetic Engineering & Biotechnology News
In the US-based Genetic Engineering & Biotechnology News article, Dr. Revah reviewed Genethon’s progress and challenges in developing and manufacturing gene therapies.
In addition to discussing Genethon’s gene therapy products, Revah detailed how Genethon is working to address the high price tags associated with gene therapies: “We work on rare and ultra-rare diseases. If we (as an industry) don’t decrease the costs, it will be hard getting these drugs to the patients affected by rare diseases. The cost of manufacturing some of the drugs can be in the million-of-dollars range. We want them to be in the tens-of-thousands-of-dollars range.”
Read the article “Make CGT More Affordable with Efficient BioManufacturing,” which was published October 7, 2025.
Pharma Boardroom
In an interview with UK-based Pharma Boardroom, Dr. Revah detailed Genethon’s more than three decades of research and development and its current pipeline of 15 clinical programs, including gene therapies in late-stage trials for Duchenne muscular dystrophy, Crigler-Najjar syndrome and Leber Hereditary Optic Neuropathy. He also discussed Genethon’s partnerships with biotech and pharmaceutical companies; the formation of GenoTher Cluster in Paris; and his outlook on the future of gene therapy.
“I feel a strong sense of optimism about the trajectory of gene therapy,” Dr. Revah said. “The recent ESGCT congress made clear how quickly the field is advancing and how the scope of what we can treat is expanding. We are moving beyond the early period of ultra-rare, single-patient interventions that first proved what was technically possible, and we are beginning to see credible progress in larger rare diseases.”
Read the Pharma Boardroom interview published December 12, 2025
