PMH3 Olanzapine Long-Acting Injection for Schizophrenia: an Evaluation of Patient Functioning During 24 Weeks of Maintenance Therapy

This study aimed to describe the functional level of patients treated with olanzapine long-acting injection (OLZ-LAI) during maintenance treatment of schizophrenia for up to 24 weeks. A secondary objective was to compare OLZ-LAI with oral olanzapine on these functional measures. We present a secondary analysis of a multicenter, randomized, double-blind, study comparing the safety and efficacy of OLZ-LAI (405mg/4weeks, 300mg/2weeks, 150 mgs/2weeks, active depot groups) with oral olanzapine and OLZ-LAI 45mg/4weeks (very low dose/pseudo-placebo group) for maintenance treatment of clinically stable patients with schizophrenia (n=1064). Heinrichs and Carpenter's Quality of Life Scale (QLS) mean total scores were calculated for each of the three active OLZ-LAI treatment groups and for their pooled group. Patients' functional status was also classified - at baseline and endpoint, per QLS - as “good,” “moderate” or “poor” using a recent data-driven approach to defining levels of functioning in schizophrenia. Over the 24-week treatment period, the OLZ-LAI-treated patients improved their level of functioning - per QLS total score - from a mean (±SD) of 66.4 (±18.9) to 72.0(±19.1) (p<0.001). At baseline, 16.8% of the OLZ-LAI-treated patients were identified as having a “good” level of functioning, which increased to 27.5% following up to 24 weeks of therapy (p<0.001). There was a decrease both in the proportion of patients with a “moderate” level of functioning (from 66.8 to 61.8%; p=0.002) and patients with a “poor” level of functioning (from 16.3% to 10.7%; p=0.06). Results were not significantly different between oral olanzapine and the three OLZ-LAI active dosing groups or the pooled OLZ-LAI treatment group. In this 24-week study, clinically stable patients treated with OLZ-LAI maintained their favorable baseline level of functioning or further improved it over time. Results did not significantly differ between OLZ-LAI and oral olanzapine.