Background: Aripiprazole is a novel antipsychotic for the management of schizophrenia. This study investigated the efficacy, safety, and tolerability of aripiprazole in preventing relapse in adult chronic schizophrenia patients experiencing ongoing stable symptomatology.

Method: In this 26-week, randomized, double-blind, placebo-controlled, parallel-group, multicenter study, 310 patients with DSM-IV schizophrenia (mean Positive and Negative Syndrome Scale [PANSS] total score = 82) were randomly assigned to receive a once-daily fixed dose of aripiprazole, 15 mg, or placebo. The primary outcome measure was time to relapse following randomization. Secondary objectives were to assess the efficacy, safety, and tolerability of aripiprazole, 15 mg, compared with placebo, in the study population. The study was conducted between Dec. 21, 2000, and Aug. 20, 2001.

Results: The time to relapse following randomization was significantly (p < .001) longer for aripiprazole compared with placebo. More patients relapsed with placebo (N = 85; 57%) than aripiprazole (N = 50; 34%); the relative risk of relapse for the aripiprazole group was 0.59 (p < .001). Aripiprazole was significantly superior to placebo from baseline to endpoint in PANSS total, PANSS positive, PANSS-derived Brief Psychiatric Rating Scale, and Clinical Global Impressions-Severity of Illness scale (CGI-S) scores and demonstrated significantly better mean Clinical Global Impressions-Global Improvement scale scores (p <= .01 for all comparisons except CGI-S: .01 < p <= .05). Aripiprazole was well tolerated, with no evidence of marked sedation and no evidence of hyperprolactinemia or prolonged heart rate-corrected QT interval (QTc). Extrapyramidal symptoms were comparable in the aripiprazole and placebo groups. Modest mean weight loss at endpoint was evident in both groups.

Conclusion: Aripiprazole, 15 mg once daily, is an effective, well-tolerated treatment for prevention of relapse in patients with chronic, stable schizophrenia.