A randomized, 13-week study assessing the efficacy and metabolic effects of paliperidone palmitate injection and olanzapine in first-episode schizophrenia patients

This study was conducted to evaluate the efficacy and metabolic effects of paliperidone palmitate (PP) injections against oral olanzapine in first-episode schizophrenia (FES) patients. Eligible patients were randomized to receive PP or olanzapine. Efficacy assessments and weight-related parameters were assessed at baseline, weeks 1, 5, 9, and endpoint or at early withdrawal. Lipid, glucose, insulin and prolactin were evaluated at baseline and endpoint or at early withdrawal. The Positive And Negative Syndrome Scale (PANSS) scores declined significantly after treatment in both groups. Significant increases in weight-related parameters from baseline to endpoint were shown in both groups. Although there was no significant difference in PANSS scores and weight-related parameters between the two groups through the whole 13-week study. The increased level of triglyceride and HOMA-IR at endpoint from baseline in the olanzapine group was higher than the PP group. There was a stronger elevation of prolactin level in the PP group. In summary, PP and olanzapine showed similar improvement in the treatment of FES patients. This study also reinforced the necessity for regular monitoring of metabolic parameters in schizophrenia patients prescribed atypical antipsychotics. Clinical trial registration numbers: ChiCTR-IOR-14005304. Date of registration: 2014-10-11.