Behavioural changes in patients with intellectual disability treated with perampanel
Perampanel is a non‐competitive AMPA receptor antagonist recently approved in the United States of America and in Europe for the adjunctive treatment of partial‐onset seizures. Three Phase III trials of perampanel with a total of more than 1200 patients suffering from pharmacotherapy‐resistant partial‐onset seizures have been completed, followed by an extension study.12 In a post hoc analysis of these three double‐blind, randomized, placebo‐controlled Phase III studies in epilepsy patients without ID, the most common adverse events associated with perampanel were dizziness and somnolence.15 Irritability occurred only in 7% of the perampanel‐treated group.15 The majority of adverse events were only mild or moderate in severity, with a low rate of discontinuation due to adverse events.15 However, no systematic descriptions of the efficacy and tolerability of perampanel in patients with intellectual disabilities have been published. Prospective randomized double‐blind studies are rare in this patient group.
The objective of this cross‐sectional retrospective study was to assess tolerability, retention rate and efficacy during 6, 12 and 24 months of treatment with perampanel in a cohort of patients with ID, severe epilepsy and anticonvulsant polypharmacotherapy.
With regard to the limitations of a retrospective observational single‐centre study and the difficulties of observing these patients, we chose an observation time of 2 years, in order to gain reliable data concerning adverse effects and retention rate. To avoid the ethical and legal difficulties of controlled studies conducted in patients with intellectually disability, an open observational study design in accordance with the guidelines published by Linden et al.16 was chosen.