The US Food and Drug Administration (FDA) has accepted Biohaven Ltd.'s New Drug Application (NDA) for troriluzole with Priority Review status, marking a significant milestone in the treatment of spinocerebellar ataxia (SCA). This rare genetic neurodegenerative disorder currently has no FDA-approved treatments, affecting approximately 15,000 people in the United States and 24,000 in Europe and the United Kingdom.
Breakthrough in SCA Treatment
The Priority Review designation reflects the urgent unmet medical need in SCA treatment. Troriluzole, a once-daily oral medication, demonstrated remarkable efficacy in clinical trials, showing a 50-70% reduction in disease progression rate over a three-year period. This translates to a 1.5-2.2 year delay in disease advancement, offering hope to patients who currently face relentless functional decline.
Dr. Melissa Beiner, SCA Clinical Development Lead at Biohaven, emphasized the significance of this development: "The FDA decision to grant Priority Review demonstrates the extremely high unmet need in this rare neurodegenerative disease. Time is of the essence for patients with SCA, who are suffering relentless and irreversible functional decline."
Clinical Evidence and Study Design
The NDA submission was supported by compelling data from Study BHV4157-206-RWE (NCT06529146), which evaluated troriluzole 200 mg in SCA patients. The study met its primary endpoint, measuring changes in the functional Scale for the Assessment and Rating of Ataxia (f-SARA) across all SCA genotypes.
The research program incorporated data from two independent natural history cohorts in the United States and Europe, using sophisticated Propensity Score Matching to ensure rigorous comparison between treated and untreated patients. The study demonstrated statistically significant superiority across nine consecutive, prespecified primary and secondary endpoints.
Expert Perspectives
Dr. Jeremy Schmahmann, Professor of Neurology at Harvard Medical School and Founding Director of the Ataxia Center at Massachusetts General Hospital, called the development "a watershed in the history of the SCAs," noting particularly the medication's impact on reducing falls in patients.
Andrew Rosen, Chief Executive Officer of the National Ataxia Foundation, highlighted the collaborative nature of the research: "Biohaven's SCA program reflects years of dedicated clinical research and collaboration with leading world experts and advocacy groups to advance the ataxia field."
Mechanism of Action and Future Implications
Troriluzole functions as a glutamate modulator, addressing the underlying glutamate dysregulation that characterizes SCA. The drug increases glutamate uptake from synapses by enhancing the function of excitatory amino acid transporters on glial cells, potentially offering a new therapeutic approach for this devastating condition.
If approved, Biohaven plans to commercialize troriluzole in the United States by 2025. The company has already established an expanded access protocol to provide early access to eligible patients while awaiting FDA approval.
The FDA's decision on the NDA is expected within six months of filing, during the third quarter of 2025. This review timeline reflects the urgency of addressing the unmet medical need in SCA treatment, potentially offering the first approved therapy for this life-threatening disorder.
