A Pilot, 15-month, randomised effectiveness trial of Risperidone long-acting injection (RLAI) versus oral atypical antipsychotic agents (AAP) in persons with bipolar disorder

Objective: Long-acting injectible antipsychotic agents are rarely considered in the treatment of bipolar patients [bipolar disorder (BPD)]. We posited that BPD patients receiving risperidone long-acting injections [Risperidone long-acting injections (RLAIs)] would experience fewer negative clinical events than those receiving oral atypical antipsychotic agents (AAP). Methods: Adult BPD patients in a hypomanic, manic or mixed episode were randomised to either oral risperdone followed by RLAI (n = 23) or an AAP (n = 25) for 15 months. Any mood stabilizers were continued. An independent clinician board declared any clinical events that occurred but the treatment assignment was concealed. Results: Nine of the 48 patients who participated in this study did not improve, leaving 39 patients in 1-year extension. RLAI patients received the following bi-weekly dosages: 25 mg (n = 9), 37.5 mg (n = 8), and 50 mg (n = 6). The AAP group included aripiprazole (n = 11, 15-30 mg/day), quetiapine (n = 8, 300-700 mg/day), olanzapine (n = 5, 15-25 mg/day), and ziprasidone, (n = 1, 160 mg/day). In total, 47 clinical events were declared. The RLAI-treated group experienced significantly fewer clinical events (mean: 0.86 +/- 0.73) compared with the AAP group (1.61 +/- 1.29), t = 2.29, d.f. = 37, p = 0.028 (95% CI = 0.087-1.421). Of all, 50% of the AAP subjects gained >= 7% of their baseline body weight as did 38% of the RLAI-treated patients. Conclusions: RLAI-treated patients experienced significantly fewer negative clinical events. Further exploration should focus on which subtypes of BPD patients might benefit from RLAI treatment. Weight gain in BPD subjects requires clinical attention. Limitations include an open design, small sample size and the inability to conclude on whether this strategy is useful for depressive episodes.