PTC crashes as win for Novartis-partnered Huntington’s drug fails to convince investors

Title

PTC Therapeutics Shares Plunge After Huntington’s Drug Data Fails to Ease Approval Doubts

PTC Therapeutics, in partnership with Novartis, announced positive primary results from their Phase 2 PIVOT-HD trial for the Huntington's disease candidate PTC518, showing significant reduction in blood Huntingtin protein levels and a favorable safety profile5.
Despite the trial meeting its primary endpoint, PTC shares dropped by about 17-19%, indicating strong investor skepticism about the likelihood of achieving accelerated FDA approval based on the current data4 5.
The study’s reduction in Huntingtin protein was more pronounced in Stage 2 than Stage 3 patients, and analysts noted a lack of definitive data linking the mutant protein reduction with clear clinical benefit, a requirement for regulatory approval5.
Investors and analysts question whether the current results are strong enough to avoid a lengthy and expensive Phase 3 trial, casting doubt on the near-term commercial prospects of PTC5185.
PTC Therapeutics has stated that discussions about next steps and the potential for accelerated approval are ongoing, but the market remains unconvinced and sees significant regulatory hurdles ahead5.