05:08 AM EST, 11/05/2025 (MT Newswires) -- Biohaven ( BHVN ) said late Tuesday the US Food and Drug Administration has recommended in a complete response letter a meeting to discuss the evidence that will be required to support a future new drug application to treat spinocerebellar ataxia with Vyglxia, or troriluzole.

"The FDA issued a complete response letter despite Study 206-RWE being reviewed by FDA and achieving statistical significance in the study's prespecified primary and secondary outcome efficacy endpoints," the company said. "FDA cited issues that can be inherent to real-world evidence and external control studies including potential bias, design flaws, lack of pre-specification and unmeasured confounding factors."

Biohaven ( BHVN ) said it intends to meet with the FDA to discuss potential next steps.

The company also said it's launching "strategic portfolio and cost optimization" across various programs. Biohaven ( BHVN ) will focus forward-looking spend on restructuring of business priorities to achieve a roughly 60% reduction in annual direct research and development spending, it said.

Spinocerebellar ataxia is a group of dominantly inherited neurodegenerative disorders.

Biohaven ( BHVN ) shares were down 45% in recent premarket activity Wednesday.