Amisulpride versus olanzapine in the treatment of schizophrenia in Indian patients: randomized controlled trial

Objective: Atypical antipsychotics are increasingly drugs of first choice in schizophrenia. Amisulpride, a new atypical antipsychotic, is reported to be effective for both positive and negative symptoms of schizophrenia in Western countries but Indian experience is limited. The aim of the present study was therefore to conduct a trial of amisulpride versus olanzapine in Indian schizophrenia patients. Methods: Eighty adult patients of either sex were randomized to receive standard doses of the two drugs orally, in a single blind manner, for 12 weeks, with follow up at 4 and 8 weeks. Effectiveness was assessed by changes in scores on the Brief Psychiatric Rating Scale (BPRS), Scale for Assessment of Positive Symptoms (SAPS), Scale for Assessment of Negative Symptoms (SANS), and physician-administered Clinical Global Impression (CGI) scale. Tolerability was assessed by treatment-emergent adverse drug reactions (ADRs). Results: Evaluable were 39 patients on amisulpride and 38 on olanzapine. The groups were comparable at baseline with respect to demographics, illness duration and rating scores. Final BPRS score was lower for olanzapine (33.2 +/- 9.44) than for amisulpride (37.7 +/- 9.67). SAPS and SANS scores and CGI rating improved individually in both arms but remained comparable between groups throughout the study period, but olanzapine reduced SAPS score to a greater extent. ADRs were encountered in 67.5% and 47.5% of patients (p = 0.113) on amisulpride and olanzapine, respectively. Tremor and insomnia were more frequent with amisulpride, while olanzapine caused more weight gain and sedation. No serious ADRs occurred. Conclusions: Amisulpride, although comparable to olanzapine on some measures, did not match the improvement seen with the latter drug in BPRS and SAPS scores. Despite differences in ADR profiles, overall tolerability was satisfactory for both drugs. In Indian patients, amisulpride should therefore be an alternative to olanzapine to a limited extent, such as when weight gain and sedation are undesirable.