Analysis of falls in patients with epilepsy enrolled in the perampanel phase III randomized double-blind studies

Objective: To analyze occurrence of falls among patients with partial seizures, with/without secondarily generalized seizures (SGS), and primary generalized tonic-clonic seizures (PGTCS) in the perampanel phase III clinical studies.

Methods: Studies 304, 305, and 306 randomized subjects (≥12 years) with drug-resistant partial seizures (with/without SGS) to perampanel 2, 4, 8, or 12 mg or placebo for double-blind treatment. The adverse event (AE) of falls was analyzed in the Safety Analysis Set (N = 1480). Study 332 randomized subjects aged ≥12 years with a diagnosis of PGTCS into perampanel 8 mg or placebo groups for double-blind treatment. In a systematic review of reported falls in the study 332 Safety Analysis Set (N = 163), falls were queried to establish whether each was seizure related; subjects with falls resulting from a seizure were not included in this analysis.

Results: For studies 304/305/306, treatment-emergent falls occurred in 5.1% perampanel-treated versus 3.4% placebo-treated subjects with partial seizures. Exposure-adjusted rate for falls (falls/subject-month of exposure) was greater for total perampanel than for placebo (0.0175 vs. 0.0093) and was dose related for those receiving perampanel. In subjects with SGS, incidence of treatment-emergent falls was 4.3% in perampanel and 4.0% in placebo groups. Exposure-adjusted rates were 0.0169 and 0.0097 falls per subject-month of exposure in perampanel and placebo, respectively. For study 332, 2.5% perampanel-treated and 1.2% placebo-treated subjects with PGTCS had treatment-emergent falls that were not part of a seizure. Exposure-adjusted rates were 0.0169 and 0.0032 falls per subject-month of exposure in perampanel and placebo, respectively.

Significance: Results of the perampanel studies suggest that patients with epilepsy should be monitored due to the common risk of falls.