Does Olanzapine Have Advantage Over Iloperidone in Early Amelioration of Symptoms in Schizophrenia? A Randomised Parallel Group Trial

Abstract

BACKGROUND The development of more effective and safer drugs for the optimal treatment of schizophrenia has become quite essential in the present era. We find limited literature directly comparing the efficacy of the two 'atypical' antipsychotics, i.e. olanzapine and iloperidone. MATERIALS AND METHODS The study participants were persons diagnosed with schizophrenia between the age of 18-65 years who were randomised to treatment with olanzapine or iloperidone and analysed for symptoms on the basis of Positive and Negative Symptom Scores (PANSS) at 4 and 8 weeks. Statistical Analysis-Mean changes in the PANSS were analysed by paired and independent t-tests. RESULTS There was statistically significant and similar reduction in clinical symptoms at eight weeks in both olanzapine (PANSS score of 92.22 (±17.03) at baseline to 78.63 (±15.30) at 8 weeks; p<0.001) and iloperidone (PANSS score of 93.75 (±19.70) at baseline to 74.88 (±30.52) at 8 weeks; p<0.001) groups (p<0.001). Olanzapine showed significantly higher reduction (p<0.01) in PANSS as compared to iloperidone at four weeks particularly in the PANSS negative symptom score. The two groups did not differ in the treatment completion rates. CONCLUSION Though both the study drugs significantly improve the symptoms in schizophrenia, but olanzapine seems to cause an early amelioration of negative symptoms as compared to iloperidone.