Vigabatrin versus carbamazepine monotherapy for epilepsy

Area of Science:

• Neurology
• Pharmacology
• Clinical Trials

Background:

• Vigabatrin (VGB) is effective for refractory epilepsy but carries a risk of visual field defects.
• The comparative efficacy and safety of VGB monotherapy versus carbamazepine (CBZ) monotherapy for epilepsy have not been systematically reviewed.

Purpose of the Study:

• To systematically review randomized controlled trials (RCTs) comparing VGB and CBZ monotherapy for epilepsy.
• To assess the efficacy and safety profiles of VGB versus CBZ in monotherapy epilepsy treatment.

Main Methods:

• Searched multiple databases (Cochrane, MEDLINE, EMBASE, CBM) and trials registers up to October 2011.
• Included RCTs comparing VGB with CBZ monotherapy, assessing time to treatment withdrawal, remission, first seizure, and adverse events.
• Two reviewers independently assessed quality and extracted data; meta-analysis was planned but limited by outcome reporting.

Main Results:

• Five studies with 734 participants were included; only one study was of good quality.
• No significant difference was found between VGB and CBZ for time to treatment withdrawal or six-month remission.
• VGB showed a disadvantage in time to first seizure and was associated with more weight gain but less rash and drowsiness compared to CBZ.

Conclusions:

• Insufficient data exists to definitively assess the risk-benefit balance of VGB versus CBZ monotherapy for epilepsy.
• Due to the risk of visual field defects, VGB monotherapy should be used cautiously and not as a first-line treatment.
• Frequent visual field assessments are recommended if VGB is used; future research should address visual field defects and improve study methodology.