Can J Psychiatry. 2016 Aug 1. [Epub ahead of print]
Orr C, Deshpande S, Sawh S, Jones PM, Vasudev K.
OBJECTIVE: A systematic review was conducted to examine the efficacy, tolerability, and acceptability of asenapine compared with other antipsychotics in the treatment of psychotic disorders.
METHODS: Four databases, 8 trial registries, and conference presentations were searched for randomized clinical trials of asenapine versus any comparator for the treatment of any psychotic illness. Primary outcome measures were changes in the Positive and Negative Syndrome Scale (PANSS) total score and the incidence of withdrawal due to adverse effects.
RESULTS: Eight randomized clinical trials, encompassing 3765 patients, that compared asenapine with placebo (n = 5) and olanzapine (n = 3) were included. No differences were found between asenapine and olanzapine in terms of changes to PANSS total or PANSS negative subscale scores. Patients taking asenapine were more likely to experience worsening schizophrenia and/or psychosis than were those taking olanzapine. No differences were found between asenapine and olanzapine in rates of discontinuation due to adverse drug reactions or lack of efficacy, but those taking asenapine had higher rates of withdrawal for any reason than those taking olanzapine. Asenapine caused less clinically significant weight gain or increases in triglycerides than olanzapine and was more likely to cause extrapyramidal symptoms than olanzapine. In comparison to placebo, either no difference or superiority was demonstrated in favour of asenapine on all efficacy measures.
CONCLUSION: The current evidence is limited, as asenapine has been compared only with placebo or olanzapine. In the randomized clinical trials analysed, asenapine was similar or superior to placebo and similar or inferior to olanzapine on most efficacy outcomes. While asenapine demonstrated fewer adverse metabolic outcomes than olanzapine, rates of extrapyramidal symptom-related adverse effects were higher.