Adjunctive everolimus therapy for tuberous sclerosis complex‐associated refractory seizures: Results from the postextension phase of EXIST‐3. (25th October 2021)

• Record Type: Journal Article
• Authors: Franz, David N.; Lawson, John A.; Yapici, Zuhal; Ikeda, Hiroko; Polster, Tilman; Nabbout, Rima; Curatolo, Paolo; de Vries, Petrus J.; Dlugos, Dennis J.; Herbst, Fabian; Peyrard, Severine; Pelov, Diana; French, Jacqueline A.
• Is Part Of: Epilepsia. Volume 62:issue 12(2021)
• Page Start: 3029
• Page End: 3041
• Publication Date: 2021-10-25
• Subjects: epilepsy -- everolimus -- EXIST‐3 -- postextension phase -- tuberous sclerosis complex; Epilepsy -- Periodicals; 616.853
• DOI: 10.1111/epi.17099
• Languages: English
• ISSNs: 0013-9580

Abstract

Abstract: Objective: Epilepsy is highly prevalent in patients with tuberous sclerosis complex (TSC). Everolimus showed higher efficacy than placebo for seizures in the primary analysis of the EXIST‐3 study. Here, we present the long‐term outcomes of everolimus at the end of the postextension phase (PEP; data cutoff date: October 25, 2017). Methods: After completion of the extension phase, patients were invited to continue everolimus in the PEP with everolimus (targeted trough concentration = 5–15 ng/ml, investigator‐judged). Efficacy assessments included changes in seizure status during the PEP collected at 12‐week intervals as parent/caregiver‐reported data through a structured questionnaire. Results: Among 361 patients, 343 entered the extension phase and 249 entered the PEP. After 12 weeks in the PEP, 18.9% (46/244) of patients were seizure‐free since the last visit of the extension phase and 64.8% (158/244) had a stable/improved seizure status. At 24 weeks, the corresponding percentages were 18.2% (42/231) and 64.5% (149/231). Among 244 patients, the response rate was 32.8% (80/244) during the 12‐week maintenance period of the core phase and 63.9% (156/244) at the end of the extension phase. Of the 149 responders at the end of the extension phase, 70.5% were seizure‐free or had stable/improved seizure status. Long‐term efficacy data showed persistent responses were observed in 183 of 361 patients (50.7%); 63.9% of these patients had a response that lasted at least 48 weeks. The most frequent Grade 3–4 adverse events (≥2% incidence) reported throughout the study were pneumonia, status epilepticus, seizure, stomatitis, neutropenia, and gastroenteritis. Four patients died during the study. Significance: The final analysis of EXIST‐3 demonstrated the sustained efficacy of everolimus as adjunctive therapy in patients with TSC‐associated treatment‐refractory seizures, with a tolerable safety profile.