Sarepta Therapeutics' stock experienced a significant after-hours plunge of 5.38% following the release of its first-quarter 2026 financial results.

The decline was driven by a 2% year-over-year drop in quarterly revenue to $730.8 million, primarily attributed to a sharp 73% decrease in sales of its therapy ELEVIDYS. The company cited an updated product label restricting use to ambulatory patients as a key factor behind the lower sales volume for this treatment.

While the company reported a positive swing to net income of $331 million and reiterated its full-year 2026 net product revenue guidance of $1.2-$1.4 billion, investors reacted negatively to the revenue shortfall and the significant decline in its flagship ELEVIDYS product sales during the quarter.