A Double-Blind, Randomized Comparative Study of Aripiprazole and Olanzapine in Patients with Schizophrenia

Background Few studies have directly compared the efficacy and tolerability of atypical agents. Methods This multicenter, randomized, double-blind study compared the efficacy and tolerability of aripiprazole ( n = 355) with olanzapine ( n = 348) in patients with schizophrenia experiencing acute relapse. After a 6-week acute treatment phase, patients with Clinical Global Impression—Improvement = 1–3 or ≥ 20% reduction in the Positive and Negative Symptom Scale (PANSS) Total score could progress to the 46-week outpatient extension phase. Co-primary study objectives were to compare efficacy at Week 6 and weight gain liability from baseline to Week 26. Results The mean olanzapine dose was 15.4 mg/day compared with a mean aripiprazole dose of 23.0 mg/day. More patients treated with olanzapine (47%) completed the 52-week study than those treated with aripiprazole (39%); time to discontinuation was significantly in favor of olanzapine ( p p Conclusions Olanzapine had a statistically significant efficacy advantage over aripiprazole, whereas aripiprazole was associated with significantly less weight gain.