Shares of Sarepta Therapeutics (NASDAQ:SRPT) climbed about 14% after the company released preliminary clinical results from its siRNA-based pipeline targeting facio scapulo humeral muscular dystrophy type 1 (FSHD1) and myotonic dystrophy type 1 (DM1).
The Cambridge, Massachusetts-based biotechnology company reported early findings from Phase 1/2 ascending-dose studies evaluating SRP-1001 for FSHD1 and SRP-1003 for DM1. According to Sarepta, the studies demonstrated dose-dependent exposure in muscle tissue, early biomarker responses, and a favorable safety profile.
The company said the results provided proof-of-concept evidence that a single dose of either therapy can reduce levels of the targeted protein or mRNA associated with the diseases. Most reported adverse events were described as mild to moderate, and the frequency of these events did not appear to increase with higher doses.
Both investigational treatments are built on an αvβ6 integrin-targeted delivery platform, designed to improve the delivery of small interfering RNA (siRNA) into muscle cells. Sarepta said the technology is intended to overcome key challenges related to tissue delivery and safety that have limited other RNA-targeted therapies for rare genetic disorders caused by toxic RNA or abnormal protein overexpression.
Louise Rodino-Klapac, President of Research & Development and Technical Operations, said the early data showed strong siRNA delivery into muscle tissue, adding that there has been no evidence so far of saturation in muscle uptake or dose-limiting safety concerns.
Sarepta said it will discuss the results in greater detail during an investor call scheduled for March 25, 2026, at 8:30 a.m. Eastern time.