Losigamone add-on therapy in partial epilepsy: a placebo-controlled study. Efficacy and safety of Losigamone in partial seizures: a randomized double-blind study.
To evaluate the efficacy and tolerability of losigamone (LSG).
                Double-blind, placebo-controlled add-on study with 3x500 mg LSG/die for the treatment of chronic partial seizures in 203 patients (99 treated with LSG, 104 on placebo).
                The median percent change of seizures was 14.9% (LSG) versus 6.7% (placebo) (P=0.004). Seizure frequency was decreased by more than 50% in 22.3% (LSG) and 14.6% (placebo) of patients (P=0.13). Mean percent change of seizures was best in patients with only one additional anticonvulsant drug (LSG versus placebo, P=0.004). Adverse events (usually CNS-related side effects of mild to moderate intensity) were reported in 59.6% (LSG) and 37.5% (placebo) of patients.
                LSG proved to be an effective and well tolerated anticonvulsant drug for the treatment of chronic partial seizures. The objective of the study was to investigate the efficacy and safety of two different dosages of Losigamone (LSG) in add-on treatment of partial seizures. In a multi-center, double-blind, randomized clinical trial, patients received one of three 12-week treatments: placebo, LSG 1200 mg/day, or 1500 mg/day, in addition to up to three standard anticonvulsants after a prospective period of 12 weeks to assess baseline seizure frequency. The primary efficacy measure was the relative reduction of seizure frequency per 4 weeks in the double-blind phase as compared to baseline. In the intention-to-treat population of 264 patients, the relative median reduction of partial seizure frequency was 3.3% for placebo, 19.7% for LSG 1200 mg/day, and 25.3% for LSG 1500 mg/day. The differences of both LSG groups versus placebo were significant (P<0.01, two-tailed). In the responder analysis, 11.8% of the patients in the placebo group, 17.2% in the LSG 1200 mg/day group, and 29.3% in the LSG 1500 mg/day group showed a seizure reduction versus baseline of at least 50%. A positive association between dosage and response was observed (P=0.003). Adverse events during treatment were reported by 58.8% of the patients for placebo, by 62.1% for LSG 1200 mg/day and by 76.1% for LSG 1500 mg/day. Most events in the LSG groups occurred during the first 4 weeks of double-blind (during or immediately after up-titration) and subsided quickly. Over the last 4 weeks of treatment, the incidence of adverse events in the LSG groups was close to the placebo level. Based on the study's results, LSG is an effective and safe add-on drug for refractory partial epilepsy in adults.
The results of this review showed losigamone can reduce seizure frequency but was associated with more treatment withdrawals when used as an add-on therapy for people with partial epilepsy. However, trials included were of short-term duration and uncertain quality. Future well-designed randomized, double-blind, placebo-controlled trials with a longer-term duration are needed.