Intramuscular aripiprazole in the control of agitation

To evaluate response to intramuscular (IM) aripiprazole injections using secondary analyses from clinical trials.

Data from one trial in patients with bipolar I disorder and two trials in patients with schizophrenia were assembled and used for three secondary analyses. Analysis 1 looked at data from "nonsedated" patients (i.e., patients with scores < 8 [deep sleep] or 9 [unarousable] on the Agitation-Calmness Evaluation Scale [ACES]). In analysis 2, patients were subdivided into "higher" and "lower" agitation groups according to a median split on the baseline score for the Positive and Negative Syndrome Scale (PANSS) Excited Component (PEC) (median = 18). Analysis 3 looked at the patients who received a second injection within the 24-hour study period. In each analysis, the mean change from baseline in PEC scores was re-evaluated.

Analysis 1 found that nonsedated patients with bipolar I disorder and schizophrenia showed significant decreases in PEC scores following treatment with aripiprazole IM (p < 0.005). Analysis 2 found that aripiprazole IM significantly reduced agitation compared with placebo in patients with bipolar I disorder who had lower baseline agitation (p < 0.01), while patients with bipolar I disorder who had higher baseline agitation showed similarly large PEC decreases with aripiprazole (-9.9) and placebo (-7.9). Patients with schizophrenia showed significant reductions in PEC scores compared with placebo regardless of baseline level of agitation (p < 0.01). Analysis 3 found that a second injection of aripiprazole IM significantly reduced agitation in patients with bipolar I disorder or schizophrenia (p < 0.05); repeated injections were safe and well tolerated.

Improvements with aripiprazole IM appeared to be specific to core agitation symptoms, as opposed to nonspecific sedation, and to be independent of baseline level of agitation. Furthermore, patients benefited from a repeated aripiprazole injection when clinically warranted. These results address important clinical issues regarding use of aripiprazole IM in treating agitation.