PTC Therapeutics (NASDAQ: PTCT) saw its stock surge 6.79% in after-hours trading on Tuesday, following the release of its impressive third-quarter financial results. The rare disease-focused biopharmaceutical company reported a surprising profit and strong revenue growth, driven by the successful launch of its new drug Sephience.

For the quarter ended September 30, 2025, PTC Therapeutics reported total revenue of $211.0 million, representing a 7.23% increase from the same period last year and surpassing analyst estimates of $185.251 million. The company's bottom line showed a remarkable turnaround, with a net income of $15.9 million or $0.20 per share, compared to a net loss of $106.7 million or $(1.39) per share in the previous year. This significant beat on earnings surprised analysts who had expected a loss of $(1.42) per share.

The strong performance was largely attributed to the successful launch of Sephience, which generated global revenue of $19.6 million in its first quarter on the market. The company also reported 521 start forms for Sephience in the US by quarter-end, indicating strong initial uptake. Additionally, PTC Therapeutics narrowed its full-year 2025 revenue guidance to $750.0 to $800.0 million, further boosting investor confidence. The combination of better-than-expected financial results, successful product launch, and positive outlook likely contributed to the stock's after-hours rally.