Sanofi sues Sarepta over manufacturing patents for Duchenne gene therapy 

Aug. 1, 2024

Sanofi’s subsidiary, Genzyme, has launched a lawsuit against Sarepta Therapeutics alleging that the rival drugmaker has infringed on patents with its Duchenne muscular dystrophy (DMD) treatment, Elevidys.

The suit, filed in Delaware federal court, alleges that Sarepta mimics Genzyme's adeno-associated virus (AAV) vector technology used to deliver genes into the body in gene therapy treatments like Elevidys. By manufacturing Elevidys — which the lawsuit notes is handled by Catalent in two Maryland facilities — Sanofi says Sarepta is infringing on two separate patents, both of which don't expire until June 2025.

The FDA granted Sarepta accelerated approval for Elevidys last June, but only for a segment of pediatric patients with DMD — specifically, ambulatory pediatric patients aged 4-5 years who have a confirmed mutation in the DMD gene. A year later, the agency approved a label expansion to include all individuals, regardless of ambulatory status, with DMD with a confirmed mutation in the DMD gene who are at least 4 years of age.

Elevidys, with a list price of $3.2 million, is one of the most expensive treatments in the world. The therapy earned Sarepta over $200 million last year. 

Sanofi says it is seeking financial damages and a jury trial.