Atamyo Therapeutics has received regulatory clearance in Europe to initiate a Phase Ib clinical trial for its gene therapy, ATA-200, aimed at treating limb-girdle muscular dystrophy Type 2C/R5 (LGMD2C/R5), a rare genetic disease.

The Italian Medicines Agency (AIFA) and the French Medicines Agency (ANSM) have granted approval for the clinical trial application (CTA), marking a significant step in addressing a rare genetic disease.

The multicentre, open-label, dose-escalation study will assess the safety, pharmacodynamics, efficacy, and immunogenicity of a single-dose intravenous administration of ATA-200 in paediatric patients.

This gene therapy involves delivering a normal copy of the gene for the production of the g-sarcoglycan protein.

In preclinical models, ATA-200 administered as a single systemic injection has shown promise with its tolerability and the ability to correct symptoms and biomarkers of the pathology.

The European Medicines Agency (EMA) has also recognised the potential of ATA-200 by granting it orphan medicinal product designation.

Atamyo Therapeutics chief medical officer Dr Sophie Olivier said: “We are thrilled to obtain our CTA approval in France and Italy for the devastating LGMD2C/R5 disease affecting primarily a paediatric population and for which there is no approved treatment.

“Atamyo plans to initiate dosing in patients for ATA-200 in the third quarter of 2024.”

The company’s portfolio extends beyond ATA-200 and is currently progressing with a clinical trial of another gene therapy, ATA-100, to treat LGMD2I/R9, which involves deficiencies in the FKRP protein.

In September 2022, the company announced the dosing of the first subject in a Phase I/II trial of ATA-100 to treat LGMD2I/R9.

In addition, Atamyo is conducting investigational new drug application (IND)-enabling studies of this gene therapy for LGMD2A/R1, associated with deficiencies in the calpain protein.

Atamyo Therapeutics CEO Stéphane Degove said: “This is a significant milestone for LGMD-2C/R5 patients and Atamyo, as ATA-200 is the first treatment targeting LGMD-2C/R5 to enter clinical trials.

“With the ongoing clinical trial of ATA-100 in LGMD2I/R9, the initiation of the clinical program for ATA-200 confirms our unique capabilities in bringing to patients suffering from limb-girdle muscular dystrophies a new generation of safe and effective gene therapies.”