Sarepta Therapeutics Inc. shares skyrocketed 37.8% in Tuesday trade after the company released promising early results from a gene therapy program being developed for the rare degenerative disease Duchenne muscular dystrophy.
Tuesday marked the stock’s second-largest percentage gain in over 20 years. Its largest-ever percentage gain came in September 2016, when Sarepta’s SRPT, -0.12% first drug was approved by the Food and Drug Administration.
The results, which were confined to the first three patients enrolled in the phase 1/2a study, showed improvements in micro-dystrophin, a shortened version of the dystrophin gene that is used in gene therapy. Individuals with DMD have a mutation in that gene, affecting their production of the protein dystrophin and thus their muscular development. The disease mostly affects boys and typically kills patients before the age of 30.
Patients in the trial also had significant decreases in an enzyme called serum creatine kinase that is connected to muscle damage and is typically seen in high levels among DMD patients.