Takeda epilepsy drug fails in trials

Takeda has announced the topline data from two Phase 3 trials of soticlestat, a potential treatment for rare forms of epilepsy, specifically Dravet Syndrome and Lennox-Gastaut Syndrome. Despite the results being less than satisfactory, Takeda remains committed to exploring the drug's potential, developed in partnership with Ovid Therapeutics.

In the first of these trials, the SKYLINE study, soticlestat was tested alongside standard care against a placebo with standard care for patients suffering from refractory Dravet syndrome. The primary endpoint, which was the reduction in convulsive seizure frequency, was narrowly missed. However, soticlestat demonstrated some promising outcomes in secondary endpoints. These included improvements in the responder rate, caregiver and clinician global impression of improvement, and scales measuring seizure intensity and duration over a 16-week treatment period.

The second trial, known as the SKYWAY study, evaluated soticlestat in combination with standard care versus a placebo with standard care in patients with refractory Lennox-Gastaut syndrome. Unfortunately, soticlestat did not meet the primary endpoint, which aimed at reducing Major Motor Drop seizure frequency compared to the placebo group.

Despite not meeting the primary endpoints, Takeda observed that certain pre-specified subgroups of patients showed nominally significant treatment effects. These were noted in both primary and secondary efficacy endpoints, including caregiver and clinician global impressions of improvement and the scales for seizure intensity and duration over the same 16-week period. Takeda is continuing to analyze these results for further insights.

Soticlestat is a pioneering inhibitor of the enzyme cholesterol 24-hydroxylase and was initially co-developed by Ovid Therapeutics through Phase 2 trials. Takeda acquired the rights to the drug in 2021, paying $196 million upfront and agreeing to potential milestone payments amounting to $660 million.

In light of the mixed results from the trials, Takeda plans to engage with regulatory authorities to discuss the comprehensive data gathered from these studies. The goal is to determine the next steps for soticlestat, considering the totality of the evidence.