Intramuscular aripiprazole for the treatment of acute agitation in patients with schizophrenia or schizoaffective disorder: a double-blind, placebo-controlled comparison with intramuscular haloperidol

Introduction 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. Materials and methods 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 >= 2 and >= 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. Results 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%). Conclusion These results show that IM aripiprazole is an effective treatment, comparable to IM haloperidol, and well-tolerated for acute agitation in patients with schizophrenia.