• atypical antipsychotics;
  • bipolar disorder;
  • long acting injectable risperidone;
  • mania

Objective:  To determine the safety and effectiveness of long-acting injectable risperidone (LAI-ris) add-on in bipolar patients.

Method:  A 6-month, open-label, randomized, pilot trial enrolled 49 bipolar out-patients who were taking a mood stabilizer and an atypical antipsychotic (AAP). Patients were maintained on a mood stabilizer and were randomized to continuation of their current AAP or switched to LAI-ris treatment. Safety outcomes included adverse events and changes in vital signs, laboratory tests and extrapyramidal symptoms (EPS). Effectiveness measures included Clinical Global Impression-Severity, scales assessing mania, depression, anxiety, resource utilization, quality of life, subject satisfaction with treatment, and time to intervention.

Results:  Twenty-three subjects were randomized to LAI-ris and 26 to oral AAP. There were no significant differences between the groups in adverse events, EPS change scores, weight or other safety measures. LAI-ris group had significant reductions in symptoms as measured by changes in Clinical Global Impression-Severity scores and Young Mania Rating Scale at endpoint relative to baseline and oral AAP group had reductions in Hamilton Anxiety Rating Scale scores relative to baseline but no significant differences were noted between the groups on any of the efficacy measures.

Conclusion:  LAI-ris demonstrated similar effectiveness, safety and tolerability compared to oral AAP in this 6 month pilot trial.