The efficacy and safety of lower doses of aripiprazole for the treatment of patients with acute exacerbation of schizophrenia. Intramuscular aripiprazole for the treatment of acute agitation in patients with schizophrenia or schizoaffective disorder: a double-blind, placebo-controlled comparison with intramuscular haloperidol. Aripiprazole, an antipsychotic with a novel mechanism of action, and risperidone vs placebo in patients with schizophrenia and schizoaffective disorder.
Efficacy and safety of aripiprazole administered at doses lower than those previously studied systematically were investigated in patients with acute exacerbation of schizophrenia.
                In this double-blind, multicenter study, 367 patients requiring inpatient hospitalization for acute relapse of schizophrenia were randomized to one of three fixed doses of aripiprazole (2, 5, or 10 mg/day) or placebo for 6 weeks. Efficacy and safety parameters were assessed weekly. Primary outcome measure was mean change from baseline in Positive and Negative Syndrome Scale (PANSS) Total score at endpoint.
                Aripiprazole 10 mg/day produced statistically significantly greater improvements from baseline compared with placebo for PANSS Total at endpoint (-11.3 vs -5.3; P=.03) and at weeks 2-5. Aripiprazole 5 mg/day did not produce significantly greater improvement in PANSS Total compared with placebo at endpoint, although significant differences were seen at weeks 3-5. No statistically significant improvements compared with placebo were achieved with aripiprazole 2 mg/day at any time points. All aripiprazole doses were well tolerated. Aripiprazole was not associated with significant extrapyramidal symptoms.
                While aripiprazole 5 mg/day warrants further study, the 10 mg/day dose provides effective and well-tolerated therapy for management of acute psychosis in patients with schizophrenia. This double-blind, placebo-controlled study investigated the efficacy and safety of intramuscular (IM) aripiprazole and IM haloperidol for the treatment of acute agitation in patients with schizophrenia or schizoaffective disorder.
                Four-hundred and forty-eight patients were randomized (2:2:1 ratio) to IM aripiprazole 9.75 mg, IM haloperidol 6.5 mg, or IM placebo. Patients could receive up to three injections over the first 24 h, with second and third injections administered > or =2 and > or =4 h, respectively, after the first if deemed clinically necessary. Primary efficacy measure was mean change in Positive and Negative Syndrome Scale Excited Component (PEC) score from baseline to 2 h.
                Mean improvement in PEC at 2 h was significantly greater for IM aripiprazole (-7.27) vs placebo (-4.78; p<0.001); IM aripiprazole was noninferior to IM haloperidol (-7.75) on PEC. All secondary efficacy measures showed significantly greater improvements at 2 h for IM aripiprazole and IM haloperidol over placebo. Mean number of injections/patient and percentage of patients requiring benzodiazepines were significantly lower for IM aripiprazole vs placebo (p<0.01). IM aripiprazole was well tolerated. Extrapyramidal symptom-related adverse events were similar for aripiprazole (1.7%) and placebo (2.3%) and lower than with haloperidol (12.6%).
                These results show that IM aripiprazole is an effective treatment, comparable to IM haloperidol, and well-tolerated for acute agitation in patients with schizophrenia. Aripiprazole is a dopamine D2 receptor partial agonist with partial agonist activity at serotonin 5HT1A receptors and antagonist activity at 5HT2A receptors. This multicenter trial examined the efficacy, safety, and tolerability of aripiprazole in patients with acute exacerbation of schizophrenia or schizoaffective disorder.
                In this 4-week double-blind study, 404 patients were randomized to 20 mg/d (n = 101) or 30 mg/d (n = 101) of aripiprazole, placebo (n = 103), or 6 mg/d of risperidone (n = 99). Efficacy assessments included Positive and Negative Syndrome Scale (PANSS) scores and Clinical Global Impression scores. Safety and tolerability evaluations included extrapyramidal symptoms and effects on weight, prolactin, and corrected QT (QTc) interval.
                Aripiprazole (20 and 30 mg/d) and risperidone (6 mg/d) were significantly better than placebo on all efficacy measures. Separation from placebo occurred at week 1 for PANSS total and positive scores with aripiprazole and risperidone and for PANSS negative scores with aripiprazole. There were no significant differences between aripiprazole and placebo in mean change from baseline in the extrapyramidal symptom rating scales. Mean prolactin levels decreased with aripiprazole but significantly increased 5-fold with risperidone. Mean change in QTc interval did not differ significantly from placebo with any active treatment group. Aripiprazole and risperidone groups showed a similar low incidence of clinically significant weight gain.
                Aripiprazole is effective, safe, and well tolerated for the positive and negative symptoms in schizophrenia and schizoaffective disorder. It is the first non-D2 receptor antagonist with clear antipsychotic effects and represents a novel treatment development for psychotic disorders.
Aripiprazole may be effective for the treatment of schizophrenia. Aripiprazole has a lower risk of raised prolactin and prolongation of the QTc interval. Clearly reported pragmatic short-, medium- and long-term randomised controlled trials should be undertaken to determine its position in everyday clinical practice.