Why Is Biohaven Stock Falling On Thursday?

Core Viewpoint - Biohaven Ltd. experienced a significant decline in share price following the FDA's unexpected three-month delay in the review of its rare-disease drug, troriluzole, for spinocerebellar ataxia (SCA) [1][6]. Group 1: Drug Information - Troriluzole, if approved, would be the first FDA-approved treatment for SCA, a neurodegenerative disorder affecting approximately 15,000 people in the U.S. and 24,000 in Europe and the UK [2]. - The drug has shown a favorable benefit-risk profile, with clinical data indicating it can slow disease progression by 50-70% and reduce the risk of falls [4]. Group 2: FDA Review Process - The FDA extended the PDUFA date for the new drug application (NDA) to the fourth quarter of 2025, up from the previously expected third quarter of 2025, to allow for a full review of recent submissions [1][4]. - The FDA did not raise any new concerns during the review process, and an advisory committee meeting is planned, although no date has been set [3][4]. Group 3: Financial and Market Impact - Biohaven has a non-dilutive capital agreement with Oberland Capital Management worth up to $600 million, with $250 million received to support SCA launch planning and ongoing operations [5]. - Following the news of the delay, Biohaven's shares fell by 14.3%, trading at $16.85 [8]. Group 4: Analyst Perspectives - Analysts at William Blair expressed surprise at the delay, noting the increased regulatory uncertainty but maintained an Outperform rating based on the likelihood of approval [6][7]. - They believe the FDA may exhibit more regulatory flexibility due to the rare-disease nature of SCA and the lack of treatment options [7].