Biohaven provides an update on phase II/III trial of troriluzole as a symptomatic treatment in mild-to-moderate Alzheimer's disease.

Biohaven announced that it has completed a focused analysis of the topline co-primary and key secondary data from its Phase II/III clinical trial of troriluzole as a symptomatic treatment in mild-to-moderate Alzheimer's disease (AD). Additional secondary and exploratory efficacy analyses and biomarker data including neurofilament light chain (NfL), neurogranin, tau and amyloid are still pending and expected in the coming months. Troriluzole did not statistically differentiate from placebo at 48 weeks on the study's prespecified co-primary endpoints on the Alzheimer's Disease Assessment Scale-Cognitive Subscale 11 (ADAS-cog) and the Clinical Dementia Rating Scale Sum of Boxes (CDR-SB) in study participants with mild-to-moderate AD. Troriluzole also did not differentiate from placebo on the key secondary measure of hippocampal volume assessed by magnetic resonance imaging (MRI) in the overall population. A subgroup analysis consisting only of mild AD patients did, however, reveal that troriluzole exhibited a nonsignificant numerical difference of a potential benefit at week 48 on both the ADAS-cog and hippocampal volumetric MRI. Troriluzole treated participants with mild AD (n=48) had a mean deformation change from baseline hippocampal volume of -1.1% versus -1.6% for placebo treated (n=49) participants [difference -0.5%, p-value = 0.2] at week 48. Although the numerical effects on the ADAS-cog and hippocampal MRI measured in mild AD patients suggests a potential biologic effect of troriluzole in patients with early stage disease, additional analyses and biomarker data will be informative and help determine whether any further study in early AD is warranted. Full study results, including additional secondary and exploratory outcomes, biomarker, and subgroup analyses, are expected in the coming months and will be presented at an upcoming scientific meeting. With regard to safety and tolerability, treatment with troriluzole at a dose of 280 mg once daily was relatively well tolerated and demonstrated a safety profile consistent with previous studies of troriluzole. Biohaven is planning to amend the ongoing long-term extension study of troriluzole in AD for mild AD patients to be able to continue treatment in order to gather additional clinical and biomarker data.