A comparison of two doses of melperone, an atypical antipsychotic drug, in the treatment of schizophrenia.

Melperone at a dose of 300 mg/day has been reported to be as effective as thiothixene and superior to placebo in the treatment of schizophrenia. Limited ability to cause extrapyramidal side effects (EPS) and absence of an effect on plasma prolactin (pPRL) levels suggests that it is an atypical antipsychotic drug. The goal of this pilot study was to determine: (1). the ability of melperone 400 mg/day to produce greater improvement in psychopathology than melperone 100 mg/day; and (2). to compare side effects of these two doses of melperone. Melperone, 100 or 400 mg/day, was administered to 34 acutely hospitalized patients with schizophrenia for 6 weeks in a randomized, double-blind manner. Psychopathology, EPS, pPRL levels, and body mass index (BMI) were evaluated at baseline and 6 weeks. Twenty-seven completed the 6-week treatment. A last carried forward analysis revealed no significant difference in the ability of the two doses of melperone to improve psychopathology as measured by the Brief Psychiatric Rating Scale (BPRS)-Total and Positive subscale, the Scale for the Assessment of Negative Symptoms (SANS), the Schedule for Affective Disorders and Schizophrenia-Disorganization subscale, and the Global Assessment Scale (GAS). Treatment with melperone was not associated with exacerbation of EPS, or an increase in pPRL levels or BMI. The Abnormal Involuntary Movement Scale (AIMS) was not significantly changed by treatment with melperone. These results suggest that melperone was equally effective at doses 100 and 400 mg/day, for ameliorating psychopathology and improving overall psychiatric status in patients with schizophrenia. However, the lack of difference and a placebo control group, as well as modest degrees of change in psychopathology, require caution about assuming efficacy of either dose. The lack of significant side effects such as exacerbation of EPS, pPRL elevation, and weight gain indicates melperone is well tolerated.