Trigriluzole fails in spinocerebellar ataxia Phase II/III trial

Biohaven Pharmaceutical (NYSE: BHVN) today reported disappointing top-line results from its Phase II/III clinical trial evaluating trigriluzole compared to placebo for the treatment of patients with spinocerebellar ataxia (SCA), with the news sending its shares plunging 32.5% to $25.24 in pre-market trading.

The eight-week trial dosed 141 adult SCA patients at 18 centers in the USA. In this trial, trigriluzole did not differentiate from placebo on the primary endpoint of the mean change from baseline on the Scale for the Assessment and Rating of Ataxia (SARA) after eight weeks of treatment.

After eight weeks of treatment, trigriluzole treated subjects demonstrated an improvement of -0.81 points [95% CI: -1.4 to -0.2] on the SARA versus -1.05 points [95% CI: -1.6 to -0.4] improvement in placebo, p-value = 0.52.  Placebo response in this genetically defined disorder was higher than expected based upon prior European randomized controlled trials in SCA (Romano et al 2015; Ristori et al 2010).