Sarepta Plummets After A Second Gene Therapy Patient Dies

Sarepta Therapeutics' stock (SRPT) plummeted 42.1% after announcing a second patient death following treatment with its Duchenne muscular dystrophy gene therapy, Elevidys, leading to a pause in a Phase 3 study and suspended shipments for non-ambulatory patients. Analysts have significantly slashed sales expectations for Elevidys, with Needham cutting revenue projections to $969 million from $1.4 billion, and RBC Capital downgrading its price target on SRPT. The safety event raises concerns about potential FDA intervention, particularly given the agency's new leadership and prior criticisms of Elevidys' approval, though the impact on the larger ambulatory patient population remains uncertain.

Analysis

Sarepta Therapeutics (SRPT) stock plummeted 42.1% to $20.94, its lowest point since mid-2016, after the company reported a second patient death from acute liver failure following treatment with its Duchenne muscular dystrophy (DMD) gene therapy, Elevidys. Both deceased patients were non-ambulatory. Consequently, Sarepta has paused dosing in a Phase 3 study for non-ambulatory patients and suspended Elevidys shipments for this group, while it develops an enhanced immunosuppressive regimen, though its near-term impact on risk perception is uncertain. Analyst outlooks have soured significantly: RBC Capital Markets cut its price target on SRPT to $25 from $58, and Needham slashed its Elevidys annual revenue forecast to $969 million from $1.4 billion, excluding non-ambulatory patients, and its stock price target to $50 from $125. The situation is further complicated by regulatory uncertainty, as the FDA's Center for Biologics Evaluation and Research is now led by Vinay Prasad, an outspoken critic of Elevidys' approval, increasing the perceived risk of the FDA restricting Elevidys' label to ambulatory patients or even removing it for non-ambulatory patients, who represent about 50% of all DMD cases. While some analysts suggest that removing approval for non-ambulatory patients (who currently represent a smaller portion of projected sales for some analysts like Leerink) could paradoxically boost demand among ambulatory patients, others, like RBC's Abrahams, warn that safety concerns, given observed elevated liver enzymes even in ambulatory patients, are likely to negatively impact uptake across the board.

Key Decisions for Investors

• Investors should anticipate significant near-term volatility and reassess SRPT's risk profile due to the critical Elevidys safety events, the resultant 42.1% stock decline, and the suspension of its revenue guidance.
• Closely monitor upcoming FDA communications and decisions regarding Elevidys' market status, as potential label restrictions for non-ambulatory patients or broader safety warnings could materially impact future revenue projections, which analysts have already substantially reduced.
• Exercise caution, as the path to regaining investor confidence appears challenging; the efficacy of proposed mitigation strategies like enhanced immunosuppression is unproven, and the new, critical FDA leadership overseeing biologics poses a significant regulatory overhang that could affect Elevidys' viability across all patient segments.