BACKGROUND: Epilepsy is a common neurologic disorder, affecting approximately 50 
million people worldwide; nearly a third of these people are not well controlled 
by a single antiepileptic drug and usually require treatment with a combination 
of two or more antiepileptic drugs. In recent years, many newer antiepileptic 
drugs have been investigated as add-on therapy for partial epilepsy; losigamone 
is one of these drugs and is the focus of this systematic review.
OBJECTIVES: To investigate the efficacy and safety of losigamone when used as an 
add-on therapy for partial epilepsy.
SEARCH METHODS: We searched the Cochrane Epilepsy Group Specialized Register (1 
May 2012), the Cochrane Central Register of Controlled Trials (CENTRAL Issue 4 
of 12, The Cochrane Library, 2012) and MEDLINE (1 May 2012). We searched trials 
registers and contacted the manufacturer of losigamone and authors of included 
studies for additional information. There were no language restrictions.
SELECTION CRITERIA: Randomized controlled add-on trials comparing losigamone 
with placebo for partial epilepsy.
DATA COLLECTION AND ANALYSIS: Two review authors independently assessed trial 
quality and extracted data. The primary outcomes were 50% or greater reduction 
in seizure frequency and seizure freedom; the secondary outcomes were treatment 
withdrawal and adverse events. Results are presented as risk ratios (RR) with 
95% confidence intervals (CIs) or 99% CIs (for the individual listed adverse 
events to make an allowance for multiple testing).
MAIN RESULTS: Two trials involving a total of 467 patients were eligible for 
inclusion. Both trials assessed losigamone 1200 or 1500 mg/d as an add-on 
therapy for partial epilepsy. One trial was assessed as being of good 
methodologic quality while the other was of uncertain quality. For the efficacy 
outcomes, results did show patients taking losigamone were significantly more 
likely to achieve a 50% or greater reduction in seizure frequency (RR 1.75; 95% 
CI 1.14 to 2.72), but associated with a significant increase of treatment 
withdrawal when compared with those taking placebo (RR 2.16; 95% CI 1.28 to 
3.67). For the safety outcomes, results indicated the proportion of patients who 
experienced adverse events in the losigamone group was higher than the placebo 
group (RR 1.34; 95% CI 1.00 to 1.80), dizziness was the only adverse event 
significantly in relation to losigamone (RR 3.82; 99% CI 1.69 to 8.64). The 
proportion of patients achieving seizure freedom was not reported in either 
trial report. A subgroup analysis according to different doses of losigamone 
showed that a higher dose of losigamone (1500 mg/d) is associated with a greater 
reduction in seizure frequency than lower doses, but is also associated with 
more dropouts due to adverse events.
AUTHORS' CONCLUSIONS: 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.