Suicidality-related TEAEs in the phase III, double-blind, partial seizure population included suicidal ideation in two controls (0.5%) and in two patients (0.2%) receiving perampanel. Intentional drug overdose occurred in one patient (0.1%) receiving perampanel. Two events, suicidal ideation in a patient receiving perampanel (8 mg) and intentional drug overdose in another patient receiving perampanel (12 mg), were SAEs. All three patients who were taking perampanel and reported suicidality-related TEAEs discontinued the study. None of the patients receiving placebo discontinued because of suicidality-related TEAEs. There were no deaths reported in the phase III, double-blind, partial seizure studies.
Among 1,651 patients receiving perampanel from the broader, all-treated partial seizure population, 18 (1.1%) had suicidality-related TEAEs, compared with two (0.4%) of 510 patients receiving placebo. For this broader population, when accounting for duration of exposure to the study drug, the exposure-adjusted rate for TEAEs related to suicidality in perampanel-treated patients was similar to the rate for patients treated with placebo. Of the 18 patients receiving perampanel with suicidality-related TEAEs, 13 had SAEs and 11 discontinued. No deaths due to TEAEs were related to suicidality. Among the 2,717 patients without epilepsy treated with perampanel, suicidality-related TEAEs were observed in two patients with neuropathic pain and three with Parkinson’s disease. Four events were SAEs, and one led to discontinuation. Volunteers from phase I studies did not report any suicidality-related TEAEs.
The study was based on spontaneous reports of suicidality, rather than formal suicidality scales. Despite this limitation, the study is important for assessing “whether there is a signal in the data indicating a possible concern. Fortunately, the risk of suicidality based upon this data appears to be low,” he said. The studies were supported by Eisai, the developer of the drug.
—Jake Remaly
