Shares of Sarepta Therapeutics plummeted 21.03% on Tuesday, following a double blow of negative news for the gene therapy developer. The significant drop was triggered by two major factors: the appointment of a new FDA official known for his criticism of the agency and the company's disappointing first-quarter results coupled with lowered revenue guidance.

The U.S. Food and Drug Administration named Dr. Vinay Prasad as the new director of its Center for Biologics Evaluation and Research (CBER), which oversees the regulation of gene therapies and vaccines. Prasad, known for his criticism of the FDA and skepticism towards COVID-19 vaccine mandates, raised concerns among investors about potential stricter regulations in the gene therapy sector. This appointment sent shockwaves through the biotech industry, with several gene therapy developers experiencing significant stock declines.

Adding to the pressure, Sarepta Therapeutics reported its first-quarter results after market close, revealing a larger-than-expected loss and a reduction in its full-year revenue guidance. The company reported a quarterly adjusted loss of $3.42 per share, significantly wider than the analyst consensus estimate of a $0.95 loss. Despite reporting revenue of $744.86 million, which beat expectations, Sarepta lowered its 2025 total net product revenues guidance to $2.3 billion to $2.6 billion, down from the previous forecast of $2.9 billion to $3.1 billion. CEO Doug Ingram cited "headwinds" faced by the company, prompting actions to address these challenges. The combination of regulatory uncertainty and reduced financial outlook has severely impacted investor confidence in Sarepta Therapeutics' near-term prospects.