FDA Won’t Review Biohaven’s Application to Market Treatment for Rare Neuromuscular Disease

Rare Daily Staff

The U.S. Food and Drug Administration told Biohaven that it would not review its recently submitted new drug application for its experimental therapy troriluzole for the rare neuromuscular disease spinocerebellar ataxia because the study’s primary endpoint was not met and that would not permit a substantive review.

Biohaven may request a meeting within 30 days with the FDA to discuss a path forward. The company said it is committed to working closely with the agency to bring troriluzole to people with SCA3 as quickly as possible given no therapy is currently approved for this ultra-rare genetic disorder.

Spinocerebellar ataxia (SCA) is a group of dominantly inherited disorders characterized by progressive ataxia affecting coordination of hands, arms, and legs as well as balance and speech. Patients experience significant morbidity, including progression to a wheelchair, impaired gait leading to falls, inability to communicate due to speech impairment, difficulty swallowing, and premature death. While signs and symptoms can appear anytime from childhood to late adulthood, SCA typically presents in early adulthood and progresses over the years. The range of symptoms and rate of progression of disease depend on the type of SCA, age of onset, and other genetic factors. Currently, there are no FDA-approved treatments and there is no cure for SCA.

Troriluzole is a third-generation prodrug and new chemical entity that modulates glutamate, the most abundant excitatory neurotransmitter in the human body. The primary mode of action of troriluzole is reducing synaptic levels of glutamate. Troriluzole increases glutamate uptake from the synapse, by augmenting the expression and function of excitatory amino acid transporters located on glial cells that play a key role in clearing glutamate from the synapse.

Vlad Coric, chairman and CEO of Biohaven, expressed disappointment over the FDA’s refusal to review all of the data.

“The risk-benefit profile for troriluzole warranted careful consideration by the FDA for this ultra-rare disorder,” he said.

He noted that approximately 200 patients have been treated with troriluzole for up to three years (whose diagnosis has been confirmed with genetic testing), and the troriluzole treated cohorts have remained stable compared to the untreated natural history cohorts who show marked disease progression over that similar time period.

“We believe the NDA package is compelling and shows that treatment with troriluzole leads to clinically meaningful treatment benefits including significantly delaying disease progression and reduction in falls,” he said. “We stand by these data and analyses.”

Vlad Coric, chairman and CEO of Biohaven