Naturalistic effectiveness trials of atypical antipsychotics are needed to provide broader information on efficacy, safety, and tolerability in patients with schizophrenia treated in a community practice setting.

In this 26-week, open-label, multicentre study, patients with schizophrenia requiring a switch in antipsychotic medication because current medication was not well tolerated and/or clinical symptoms were not well controlled were randomized to receive aripiprazole or an atypical antipsychotic standard of care (SOC) treatment (i.e., olanzapine, quetiapine, or risperidone based on the investigator's judgment of the optimal treatment for the individual patient and the patient's prior response to antipsychotic medication). The primary objective was to compare the effectiveness of a 26-week treatment of aripiprazole versus SOC, as measured by the Investigator Assessment Questionnaire (IAQ) total score at Week 26 last observation carried forward (LOCF) (primary endpoint), a validated measure that monitors relief or worsening of 10 key symptoms associated with the psychopathology of schizophrenia and side effects of antipsychotic treatment. Secondary objectives were to further assess effectiveness using the Clinical Global Impression - Global Improvement (CGI-I) and Clinical Global Impression - Severity of Illness scale, to assess time to treatment discontinuation, patient preference of medication, quality of life, and the tolerability of aripiprazole compared with SOC.

Aripiprazole treatment (n=268) resulted in significantly better effectiveness than SOC treatment (n=254; P<0.001; Week 26 LOCF) as evidenced by the IAQ total score beginning at Week 4 (the first assessment point) and sustained through Week 26. A similar relationship was demonstrated among patients who completed the study (observed cases analysis); aripiprazole was associated with significantly better effectiveness at all time points with a greater differential effect from SOC over time. Patients treated with aripiprazole also demonstrated significantly greater improvements on the CGI-I scale (responder rate, P=0.009 at Week 26 LOCF), as well as on quality of life (Quality of Life scale total score; P<0.001 at Week 26). Furthermore, a significantly higher proportion of patients receiving aripiprazole rated their study medication as “much better” on the Preference of Medication Questionnaire (POM) scale than their pre-study medication compared with SOC patients (P<0.001; Week 26). Time to treatment discontinuation and rates of discontinuation due to adverse events were similar in both treatment groups. The incidence of patients with one or more extrapyramidal symptom (e.g., akathisia, dystonia, parkinsonian events, and residual events) was higher in patients receiving aripiprazole compared with patients treated with SOC (13.5% vs. 5.6%); however, a higher proportion of patients in the SOC-treated group had clinically significant weight gain (21.2% vs. 7.3% for aripiprazole) and potentially clinically relevant elevated fasting levels of total cholesterol, low-density lipoprotein cholesterol, triglycerides, and serum prolactin compared with patients receiving aripiprazole.

Aripiprazole is an effective atypical antipsychotic for the treatment of schizophrenia, demonstrating better effectiveness than SOC agents used in this study in patients for whom a switch in antipsychotic medication was warranted.