A survey comparing lamotrigine and vigabatrin in everyday clinical practice

Abstract

The objective of this study was to compare the efficacy and tolerability of two new antiepileptic drugs, lamotrigine (LTG) and vigabatrin (GVG) in everyday clinical practice. A comprehensive retrospective survey of a computerized data base and hospital case notes was carried out at the Mersey Regional Epilepsy Clinic (MREC), Liverpool, which services a population of 3 million in the North West of England. The study comprised 333 out-patients with refractory epilepsy exposed to LTG and GVG forming a subset in a total population of 2250 patients with epilepsy held on a comprehensive database. The main outcome measures were duration of treatment with each drug described by a Kaplan-Meier survival curve, seizure control determined by a 50% decrease in seizure frequency and freedom from seizures, and incidence of adverse drug effects leading to discontinuation. The Kaplan-Meier curve indicated a 57% probability of patients continuing to take LTG and 43% GVG after 40 months. A 50% improvement in seizure control followed the addition of LTG in 45% of patients, with 10% seizure free, compared with 32% and 6%, respectively after the addition of GVG. LTG was discontinued because of adverse events (most frequently skin rash) in 15% of patients compared to GVG in 25% (particularly because of personality disturbance and psychiatric disorder). Both LTG and GVG are effective new AEDs in patients with refractory epilepsy, treated in a tertiary referral out-patient setting. LTG has a broader spectrum of antiepileptic efficacy for patients with both partial and idiopathic generalized seizures, whereas GVG should be reserved for patients with partial seizures at low risk of psychiatric disorder.