Sarepta Therapeutics (SRPT) is facing increased uncertainty due to Peter Marks's resignation from the Food and Drug Administration, a recent patient death and physicians being "more lukewarm" on the company's Elevidys gene therapy for Duchenne muscular dystrophy, RBC Capital Markets said in a Monday note.

Analysts, including Brian Abrahams, said they spoke with four doctors who have treated patients with Elevidys. While none expect to significantly change their use of the gene therapy in ambulatory patients following the recent patient death, all were indifferent about the product overall and uncertain about its benefits or long-term effectiveness. The analysts said that although they expect limited immediate impact, there might be an impact in H2. They updated the estimate for 2025 US Elevidys sales to $2.05 billion, compared to the $2.14 billion consensus.

The analysts said Marks' resignation from the FDA on Friday removes a key supporter of Sarepta's programs and could increase regulatory uncertainty. They said that while they don't expect Elevidys to be taken off the market, it may face more scrutiny from the regulator. Other near- and medium-term regulatory risks include the European Medicines Agency's review of Elevidys and the upcoming confirmatory data needed to maintain US approval for their phosphorodiamidate morpholino oligomers, the analysts said, adding that on the positive side, Marks' departure could make it harder for competing Duchenne muscular dystrophy gene therapies to enter the market, potentially reducing negative stock impact from progress by other companies.

RBC analysts said that while they continue to believe shares "may fundamentally underappreciate future cash flows from Elevidys and the platform, it is tougher to pinpoint what gets shares to work, even from currently depressed levels."

RBC downgraded Sarepta Therapeutics to sector perform from outperform, and cut its price target to $87 from $161.

Shares were down more than 9% in recent trading activity.

Price: 63.96, Change: -6.45, Percent Change: -9.16