Efficacy of Soticlestat Treatment by Seizure Type in Patients with Dravet Syndrome or Lennox–Gastaut Syndrome in a Phase 2, Randomized, Placebo-controlled Study (ELEKTRA) (P11-1.002)

Abstract

<h3>Objective:</h3> To develop a post hoc analysis of soticlestat treatment efficacy by seizure type in patients with Dravet syndrome (DS) or Lennox–Gastaut syndrome (LGS) in ELEKTRA (NCT03650452), a phase 2, randomized, placebo-controlled study of adjunctive soticlestat (≤300 mg BID, weight-adjusted) in children aged 2–17 years with DS demonstrating ≥3 convulsive seizures/28 days, or with LGS demonstrating ≥4 drop seizures/28 days at baseline. <h3>Background:</h3> DS and LGS involve developmental delay and frequent epileptic activity. The published ELEKTRA study investigated efficacy and safety of soticlestat, a cholesterol 24-hydroxylase inhibitor, in children with DS or LGS. Primary endpoint was change in convulsive (DS) and drop (LGS) seizure frequencies. <h3>Design/Methods:</h3> Post hoc efficacy analyses determined percent change in seizure frequency from baseline, by seizure type. Patients’ caregivers recorded seizure number and type throughout the baseline and full (20-week) treatment periods, including generalized tonic–clonic, focal to bilateral tonic–clonic, focal with motor signs and atonic seizures. <h3>Results:</h3> Of 141 enrolled patients, 126 (89%) completed ELEKTRA. The modified intent-to-treat population received ≥1 doses of study drug and had ≥1 efficacy assessments (DS, n=51; LGS, n=88). Median seizure frequency changes from baseline in patients with DS receiving soticlestat (placebo): generalized tonic–clonic seizures, −27.2% [n=14] (19.5%, n=21); focal to bilateral tonic–clonic seizures, −73.9% [n=9] (8.4%, n=4). Median seizure frequency changes from baseline in patients with LGS receiving soticlestat (placebo): generalized tonic–clonic seizures, −33.4% [n=17] (−20.0%, n=11); focal seizures with motor signs, −64.3% [n=10] (−21.1%, n=7); atonic seizures, −33.9% [n=16] (−17.9%; n=13); focal to bilateral tonic–clonic seizures, −41.3% [n=6] (none observed). <h3>Conclusions:</h3> Reduced median frequency of specific seizure types was observed in patients receiving soticlestat as adjunctive therapy. Investigation of soticlestat adjunctive therapy for these seizure types in other epilepsies is warranted (phase 3 studies ongoing for DS and LGS). Study funded by Takeda Pharmaceutical Company Limited. <b>Disclosure:</b> Dr. Pathi Jagannatham has received personal compensation for serving as an employee of Takeda Pharmaceuticals. Dr. Pathi Jagannatham has received personal compensation for serving as an employee of GlaxoSmithKline. Dr. Pathi Jagannatham has stock in Takeda Pharmaceuticals. Dr. Pathi Jagannatham has stock in GlaxoSmithKline. Dr. Dlugos has received research support from NIH. The institution of Dr. Dlugos has received research support from The Epilepsy Study Consortium. Yasir Khan has nothing to disclose. Dr. Hsiao has received personal compensation for serving as an employee of Takeda Pharmaceutical Company. Dr. Hsiao has stock in Takeda Pharmaceutical Company. Dr. Benitez has received personal compensation for serving as an employee of Takeda . Mahnaz Asgharnejad, PharmD has received personal compensation for serving as an employee of Takeda Pharmaceuticals. Mahnaz Asgharnejad, PharmD has stock in GlaxoSmithKline. Mahnaz Asgharnejad, PharmD has stock in Takeda Pharmaceuticals.