PTC Therapeutics Faces FDA Rejection On Rare Disease Treatment Over Efficacy Concerns

Core Viewpoint - The FDA issued a Complete Response Letter (CRL) to PTC Therapeutics regarding the New Drug Application (NDA) for vatiquinone, indicating that substantial evidence of efficacy was not demonstrated and additional studies are required for resubmission [1][2]. Company Developments - PTC Therapeutics expressed disappointment over the FDA's decision, emphasizing their belief in the safety and efficacy of vatiquinone for treating Friedreich's ataxia and plans to discuss the CRL with the FDA [2]. - In 2023, the MOVE-FA trial results for vatiquinone did not meet the primary endpoint of statistically significant change in the mFARS score at 72 weeks [3]. - However, in October 2024, PTC Therapeutics reported that pre-specified endpoints for two long-term extension studies were met, showing statistically significant evidence of durable treatment benefits [4]. Clinical Trial Results - The MOVE-FA long-term extension study indicated that 144 weeks of vatiquinone treatment resulted in a 3.7-point benefit on the modified Friedreich Ataxia Rating Scale (mFARS), representing a clinically meaningful 50% slowing in disease progression over three years [5]. - Results confirmed that the slowing of disease progression observed in the 72-week placebo-controlled trial was maintained over 144 weeks of treatment [6]. Regulatory Status - The FDA accepted the vatiquinone application under Priority Review in February 2025, with a target action date of August 19, following the application submission in December 2024 [6]. Market Reaction - PTC Therapeutics shares increased by 4.89% to $52.23 at the time of publication [7].