Pregabalin add-on for drug-resistant partial epilepsy

Area of Science:

• Neurology
• Clinical Pharmacology
• Evidence-Based Medicine

Background:

• Epilepsy affects 1% of the UK population, with a third experiencing persistent seizures despite medication.
• New antiepileptic drugs, including pregabalin, are developed to improve treatment outcomes for refractory epilepsy.

Purpose of the Study:

• To evaluate the efficacy and tolerability of pregabalin as an add-on therapy for drug-resistant partial epilepsy.
• To summarize evidence from randomized controlled trials (RCTs) on pregabalin's effectiveness in epilepsy management.

Main Methods:

• Searched multiple databases (Cochrane, Medline) and contacted manufacturers for relevant RCTs.
• Included double-blind, placebo-controlled trials comparing pregabalin with placebo in drug-refractory partial epilepsy.
• Analyzed outcomes including 50% seizure reduction, treatment withdrawal reasons, and adverse events using intention-to-treat analysis.

Main Results:

• Four RCTs involving 1397 participants were analyzed, testing pregabalin doses from 50 mg to 600 mg daily.
• Pregabalin significantly increased the likelihood of a 50% or greater seizure reduction compared to placebo (RR 3.56).
• Higher doses of pregabalin showed increased efficacy, but it was not associated with seizure freedom. Withdrawal due to adverse events (e.g., ataxia, dizziness, somnolence, weight gain) was significantly higher.

Conclusions:

• Pregabalin is an effective add-on treatment for drug-resistant partial epilepsy, significantly improving seizure reduction.
• Efficacy was observed for doses between 150 mg and 600 mg daily, with no plateau effect noted.
• Short trial durations necessitate longer-term studies to fully inform clinical decision-making regarding pregabalin use.