Atamyo Therapeutics Submits CTA in Europe for Limb-Girdle Muscular Dystrophy Type 2C/R5 Gene Therapy

Atamyo Therapeutics has submitted a clinical trial application (CTA) in Europe with the intention of evaluating ATA-200, an investigational adeno-associated virus (AAV) vector-based gene therapy, for the treatment of γ-sarcoglycan (SGCG)-related limb-girdle muscular dystrophy Type 2C/R5 (LGMD2C/R5).¹

Pending clearance of the CTA, the company is planning to evaluate the gene therapy in a phase 1b clinical trial (EUCT 2023-506440-16-00). Atamyo expects that the multicenter, dose-escalation study may begin dosing patients in the first half of next year. In addition to announcing the CTA submission, Atamyo also noted that it has received $8.6 million in nondilutive financing from France 2030, a program operated by Bpifrance, for ATA-200's development.

“LGMD-R5 is the most rapidly progressive and debilitating form of LGMDs with onset of symptoms in early childhood, a loss of ambulation before adulthood, and frequent cardiac impairment,” Sophie Olivier, MD, the chief medical officer of Atamyo, said in a statement.¹ “No curative treatment exists for this disease.”

ATA-200 is comprised of an AAV vector that delivers a functional copy of the SGCG gene. In the trial, the therapy will be administered intravenously. Atamyo stated that in preclinical mouse model research, the gene therapy was shown to be tolerated and able to correct for symptoms and disease biomarkers.

“ATA-200 incorporates a new promoter that enhances the liver and cardiac safety of gene therapy,” Isabelle Richard, PhD, the co-founder and chief scientific officer of Atamyo, added to the statement.¹ “This first-in-class experimental treatment represents a new hope for the patients”.

This announcement follows a positive update from the company earlier this month regarding its most advanced program, ATA-100 (previously referred to as GNT0006), which received clearance of its investigational new drug (IND) application from the FDA.^2,3 ATA-100, an AAV vector-based gene therapy that is administered as a single dose, is intended to deliver a functional copy of the human FKRP gene in order to treat fukutin-related protein limb-girdle muscular dystrophy type 2I/R9 (LGMD2I/R9). ATA-100 is currently being evaluated in a multicenter phase 1/2 clinical trial (EudraCT 2021-004276-33, NCT05224505) in Denmark, France, and the United Kingdom under CTAs that were cleared in each of those countries between 2021 and 2022.^4-6 Atamyo has also received 2 million euros worth of nondilutive public financing from Bpifrance to support this trial, which dosed its first patient in September of last year.^3,5 With the IND clearance, Atamyo intends to bring the trial to patients in the United States.²

Atamyo also has several additional LGMD gene therapy programs in the preclinical stages of development.⁷ These include potential treatments for LGMD-R1/LGMD2A (calpainopathy), LGMD-R2/LGMD2B (dysferlinopathy), and LGMD-R3/LGMD2D (deficiency in α-sarcoglycans). The LGMD-R1/LGMD2A program is currently in IND-enabling studies.¹

“We are thrilled to file this European Clinical trial and to receive such a strong public financing for the devastating LGMD2C/R5 disease” Stephane Degove, the co-founder and chief executive officer of Atamyo, added to the statement.¹ “With the ongoing clinical trial in LGMD-R9, the initiation of the clinical program for LGMD-R5/2C confirms our unique capabilities in bringing to patients suffering from limb-girdle muscular dystrophies a new generation of safe and effective gene therapies.”

REFERENCES
1. ATA-200, AtamyoTherapeutics’ gene therapy to treat limb-girdle muscular dystrophy type 2C/R5, reaches key milestones with the filing of a clinical trial application in Europe and a non-dilutive financing from France 2030 program. News release. Atamyo Therapeutics. September 19, 2023. Accessed September 28, 2023. https://atamyo.com/press-releases/https-atamyo-com-wp-content-uploads-pr-sept-19-2023-ata-200-reaches-key-milestones-with-cta-in-europe-and-france2030-financing-pdf/
2. IND for ATA-100, a gene therapy for the treatment of limb-girdle muscular dystrophy type 2I/R9 (LGMD2I/R9), cleared to proceed by FDA. News release. Atamyo Therapeutics. September 5, 2023. Accessed September 28, 2023. https://atamyo.com/press-releases/2023/ind-for-ata-100-a-gene-therapy-for-the-treatment-of-limb-girdle-muscular-dystrophy-type-2i-r9-lgmd2i-r9-cleared-to-proceed-by-fda/
3. Atamyo Therapeutics announces first patient dosed with ATA-100 gene therapy in LGMD-R9 clinical trial. News Release. Atamyo Therapeutics. September 26, 2022. Accessed September 28, 2023.https://atamyo.com/press-releases/atamyo-therapeutics-announces-first-patient-dosed-with-ata-100-gene-therapy-in-lgmd-r9-clinical-trial/
4. Atamyo Therapeutics obtains first regulatory authorization in Europe to initiate a clinical trial for ATA-100, its gene therapy to treat limb-girdle muscular dystrophy type 2I/R9. News release. Atamyo Therapeutics. December 6, 2021. Accessed September 28, 2023. https://atamyo.com/press-releases/2021/atamyo-therapeutics-obtains-first-regulatory-authorization-in-europe-to-initiate-a-clinical-trial-for-ata-100-its-gene-therapy-to-treat-limb-girdle-muscular-dystrophy-type-2i-r9/
5. Atamyo Therapeutics reaches significant regulatory and financial milestones for ATA-100, its gene therapy to treat limb-girdle muscular dystrophy type 2I/R9. News Release. Atamyo Therapeutics. February 24, 2022. Accessed September 28, 2023. https://atamyo.com/press-releases/atamyo-therapeutics-reaches-significant-regulatory-and-financial-milestones-for-ata-100-its-gene-therapy-to-treat-limb-girdle-muscular-dystrophy-type-2i-r9/
6. Atamyo Therapeutics announces significant milestones for ATA-100 and ATA-200, its gene therapy programs to treat limb-girdle muscular dystrophy 2I/R9 and 2C/R5. News release. Atamyo Therapeutics. May16, 2022. Accessed September 7, 2023. https://atamyo.com/press-releases/atamyo-therapeutics-announces-significant-milestones-for-ata-100-and-ata-200-its-gene-therapy-programs-to-treat-limb-girdle-muscular-dystrophy-2i-r9-and-2c-r5/
7. Our Pipeline. Atamyo Therapeutics. Website. Accessed September 28, 2023. https://atamyo.com/science-technology/pipeline/