Two Phase III studies of Takeda’s epilepsy drug soticlestat for patients with the rare epilepsies Lennox-Gastaut syndrome (LGS) and Dravet syndrome have missed their primary endpoints.
The candidate was being investigated by Takeda in the SKYLINE (NCT04940624) and SKYWAY (NCT04938427) studies. Head of the neuroscience unit at Takeda, Sarah Sheikh, said that the company will be engaging with authorities about the next steps with the candidate.
The SKYLINE trial was a double-blind Phase III study evaluating soticlestat plus standard of care versus placebo plus standard of care in patients with refractory Dravet syndrome. The trial missed the primary endpoint of reduction from baseline in convulsive seizure frequency. It did, however, meet some of the secondary endpoints, showing clinically meaningful and nominally significant results in the responder rate, measures of caregiver and clinician global impression of improvement, and seizure intensity and duration scales over the 16-week treatment period.
The SKYWAY trial was a double-blind Phase III study that evaluated soticlestat plus standard of care versus placebo plus standard of care in patients with LGS. The trial missed the primary endpoint of reduction from baseline in major motor drop (MMD) seizure frequency as compared with placebo.
Soticlestat was generally well tolerated in both SKYLINE and SKYWAY studies.
A previous Phase II trial (NCT03650452) investigating soticlestat as an adjuvant therapy in patients with LGS or Dravet syndrome had met its primary endpoint of reduction of seizures.
Soticlestat is a first-in-class selective inhibitor of cholesterol 24-hydroxylase (CH24H). It acts by inhibiting intracerebral CH24H, which leads to suppression of nerve cell death. The drug is being developed by Takeda following a $196m deal with the drug’s original developer, Ovid Therapeutics, in 2021.
Phase III data from other trials with soticlestat is pending and Takeda will now be hoping for a win so it can start to recoup some of those acquisition costs. On the company’s next steps, Sheikh said: “While we would have wished for more declarative results on the primary endpoints, we are encouraged by positive outcomes seen in the totality of the data and are looking forward to engaging health authorities to determine the best path forward.”
CEO of Ovid, Jeremy Levin, has also spoken out since Takeda released the Phase III data: “While SKYLINE narrowly missed its primary endpoint, we believe there are indications of effect in the secondary endpoints and the totality of the data in Dravet Syndrome patients.”
If approved, GlobalData predicts global sales for soticlestat to hit $242m in 2030. GlobalData is the parent company of Clinical Trials Arena.
