SK pharmteco, a Rancho Cordova, California-based contract development and manufacturing organization (CDMO), and Genethon, a nonprofit gene therapy research and development organization headquartered in France, are advancing manufacturing for GNT-0004, an investigational gene therapy for Duchenne muscular dystrophy (DMD), as the program progresses through Phase III clinical development.

Through its France-based subsidiary Yposkesi, SK pharmteco has supported development and manufacturing of GNT-0004, an adeno-associated virus 8 (AAV8) micro-dystrophin gene therapy. The company said its manufacturing operations have helped support the therapy’s ongoing pivotal Phase III clinical trial in Europe and the United Kingdom.

According to SK pharmteco, the collaboration also showcases its expanded viral vector manufacturing capabilities in France, where new commercial-scale infrastructure is now operational and complements manufacturing capacity in the United States.

The Genethon-SK pharmteco collaboration has manufactured, tested, and released 20 AAV8 micro-dystrophin batches at the 400-liter scale, including 18 produced under current Good Manufacturing Practice (cGMP) standards. The companies also established master and working cell banks, completed analytical method validation, and conducted stability studies supporting the program’s chemistry, manufacturing, and controls (CMC) package.

SK pharmteco said it is producing additional clinical batches while preparing process validation and documentation activities to support future commercial manufacturing.

The ongoing randomized, placebo-controlled Phase III study is expected to enroll 72 ambulatory boys ages six to 10 with DMD. According to the announcement, two-year clinical data presented earlier this year showed sustained efficacy, improvements in muscle function, and a favorable safety profile.

The announcement follows SK pharmteco’s launch last month of a global viral vector manufacturing platform supporting AAV, lentiviral, and adenoviral vector programs from early development through commercial manufacturing. The platform spans the company’s U.S. and European facilities and is designed to improve manufacturing productivity while supporting technology transfer and scale-up for gene therapy developers.