Efficacy and Tolerability of Asenapine in Acute Schizophrenia: A Placebo- and Risperidone-Controlled Trial

Objective: This 6-week trial assessed the efficacy, tolerability, and safety of the investigational psychopharmacologic agent asenapine versus placebo and risperidone in patients with acute schizophrenia (DSM-IV criteria).

Method: In a study conducted from August 2001 to May 2002, patients were randomly assigned to receive sublingual asenapine 5 mg b.i.d., placebo b.i.d., or oral risperidone 3 mg b.i.d. The primary outcome measure was improvement from baseline in Positive and Negative Syndrome Scale (PANSS) total score. Secondary outcomes included changes in Clinical Global Impressions-Severity of Illness (CGI-S) score and scores on PANSS positive, negative, and general psychopathology subscales.

Results: The intent-to-treat population comprised 174 patients who received >= 1 dose of study drug and >= 1 postbaseline assessment. At study end or last observation, mean improvements on PANSS total, negative subscale, and general psychopathology subscale scores were all significantly greater with asenapine than with placebo (p < .005, p = .01, and p < .005, respectively). Compared with placebo, improvements on CGI-S and PANSS positive subscale scores were significantly greater with both asenapine (p < .01 and p = .01) and risperidone (p < .005 and p < .05). Overall incidence rates of adverse events were comparable for asenapine and placebo, whereas risperidone was associated with substantial weight gain and prolactin elevation.

Conclusion: Asenapine was effective and well tolerated in patients with acute schizophrenia and may provide a new option for control of negative symptoms.