Comparative study of clozapine versus risperidone in treatment-naive, first-episode schizophrenia: A pilot study

Background & objectives: Clozapine may be more useful in treatment-naive patients with first-episode schizophrenia for better symptoms control and improving quality of life. The current study was carried out to compare the efficacy and tolerability of clozapine versus risperidone in treatment-naive, first-episode patients of schizophrenia. Methods: This was a comparative, open-label, six months prospective study of treatment-naive, first-episode patients with schizophrenia between the age group of 18 and 40 yr diagnosed as per the International Classification of Diseases-10 (ICD-10) criteria. A total of 63 patients were recruited and randomly assigned to clozapine group or risperidone group using computer-generated random number tables. Eight patients were lost to follow up. The dosages of the respective drugs were kept in therapeutic range of 200-600 mg/day and 4-8 mg/day orally for clozapine and risperidone, respectively. Results: On general psychopathology score, after six months of intervention, clozapine led to 60.32 per cent mean reduction in Positive and Negative Syndrome Scale (PANSS) for Schizophrenia total score while risperidone led to 56.35 per cent mean reduction in PANSS total score, which meant more improvement with clozapine. Clozapine group was found to have significant improvement in quality of life (P = 0.04339). On Glasgow Antipsychotic Side-effect Scale, clozapine was superior to risperidone. The most common side effects observed in clozapine group were oversedation (78.96%) and dizziness (55.23%), and in risperidone group, common side effects were rigidity (62.36%), sedation (38.69%), tremors (65.69%) and menstrual irregularities in 80.25 per cent of female patients. Interpretation & conclusions: The findings of this preliminary study showed clozapine as a better choice than risperidone in terms of efficacy, tolerability and better quality of life in treatment-naive, first-episode schizophrenia. However, further studies need to be done on a larger group of patients to confirm the findings.