Sarepta Plunges On Second Fatality Linked To Duchenne Gene Therapy Elevidys

(RTTNews) - Shares of Sarepta Therapeutics Inc. (SRPT) are down over 37% at $22 in premarket trading Monday, following a second fatal case linked to its Duchenne gene therapy ELEVIDYS.

ELEVIDYS is an adeno-associated virus vector-based gene therapy that is approved for the treatment of patients at least 4 years of age with Duchenne muscular dystrophy (DMD) with a confirmed mutation in the DMD gene, regardless of ambulation. Use in non-ambulatory people was approved by the FDA under accelerated approval.

The company initially reported the first patient death tied to ELEVIDYS in March 2024, which was also attributed to acute liver failure. Both fatalities have occurred in non-ambulatory DMD patients, raising significant safety concerns about the therapy's use in this patient population.

In response, the company has suspended shipments of ELEVIDYS for infusions in non-ambulatory patients in a commercial setting until an enhanced regimen is approved and in place. Moreover, the company has also paused a study dubbed ENVISION while seeking a protocol amendment to incorporate additional immunosuppression.

ENVISION is a global, randomized, double-blind, placebo-controlled trial evaluating ELEVIDYS in older ambulatory and non-ambulatory individuals living with Duchenne muscular dystrophy. In the U.S., it serves as the confirmatory trial required under the FDA's accelerated approval pathway for non-ambulatory patients.

For ambulatory patients, no treatment changes are being proposed, and the current practice of administering corticosteroids before and after ELEVIDYS infusion, along with post-treatment monitoring, remains the same, the company said.

Acute liver injury is a known potential risk associated with ELEVIDYS and other adeno-associated virus (AAV)-mediated gene therapies, a risk clearly stated in the FDA-approved prescribing information for ELEVIDYS. The company noted that while the exact cause of AAV-related liver toxicity is still unknown, current evidence points to an adaptive immune response as the likely trigger.

SRPT has traded in a range of $34.10 to $173.25 in the last 1 year. The stock closed Friday's trading at $36.18, down 3.03%.