Soticlestat shows promise in rare, severe forms of childhood epilepsy

The investigational drug soticlestat (TAK-935) helps reduce seizure frequency in children with Dravet syndrome (DS) or Lennox–Gastaut syndrome (LGS), with its safety profile consistent with previous data, according to the results of the phase II ELEKTRA trial.

ELEKTRA randomized 141 children aged 2–17 years with treatment-resistant DS (three or more convulsive seizures/month) or LGS (four or more drop seizures/month) to receive either soticlestat or placebo. The 20-week treatment period involved an 8-week dose-optimization period and a 12-week maintenance period.

Of the patients, 126 (89 percent) completed the study. The modified intent-to-treat population included 139 participants who received one or more doses of the study drug and had one or more efficacy assessments, with 51 having DS and 88 LGS.

Compared with placebo, soticlestat produced a median reduction in seizure frequency of 30.21 percent during the maintenance period (p=0.0008). Furthermore, convulsive and drop seizure frequencies decreased by 50 percent (p=0.0002) and 17 percent (p=0.1160) in the DS and LGS groups, respectively.  

The frequencies of treatment-emergent adverse events (TEAEs) were similar between the soticlestat (80.3 percent) and placebo (74.3 percent) groups, being mostly mild or moderate in severity. Serious TEAEs were documented in 15.5 percent and 18.6 percent of soticlestat- and placebo-treated participants, respectively. Lethargy and constipation were the most common TEAEs in soticlestat-treated patients. None of the patients died.