Comparative Efficacy, Safety and Tolerability of Olanzapine and Blonanserin in Patients with Schizophrenia: A Parallel Group Study

Abstract Background The antipsychotic olanzapine is a first-line drug in the treatment of schizophrenia while blonanserin is indicated in resistant cases of schizophrenia when the first line antipsychotics have failed. There are very limited studies available world-wide as well as in India that compare blonanserin with other antipsychotics in the setting of schizophrenia. Aims To study the efficacy, safety and tolerability of olanzapine and blonanserin in Schizophrenia. Settings and Design: The study was a prospective, observational, parallel group study done on schizophrenia patients aged between 18-50 years of both sexes at an outpatient Department of Psychiatry, in a tertiary medical college. The study was conducted from February 2015 to October 2016, with follow ups at weeks 4, 8 and 12. Materials and Methods The efficacy parameters were measured by the Brief Psychiatric Rating Scale (BPRS) and the Clinical Global Impression (CGI) rating. The safety parameters included the vital signs, haematological profile, lipid profile, blood sugar monitoring. Adverse drug reactions and compliance to therapy was observed through-out the study period. Appropriate statistical tests were applied to detect any significant within and between group differences using Microsoft Excel 2007 and SPSS version 17. Results There was significant decrease in the mean total score on the BPRS and CGI-S in the blonanserin arm at the 2nd and last follow up visit (p value < 0.001). Compliance was good in both groups (≤ 20% missed pills). Overall, 77 treatment-emergent adverse events were present from 56 patients. Twenty three subjects of the blonanserin arm and 33 subjects in the olanzapine arm at least experienced one adverse event (p = 0.006), metabolic adverse effects were more common with olanzapine, whereas insomnia, headache and somnolence were more often seen with blonanserin. Conclusions In the present study, blonanserin provided significantly better outcomes than olanzapine with respect to BPRS, CGI-S scores.