Dosing patterns in Europe: Efficacy and safety of risperidone long-acting injectable in doses of 25, 37.5 and 50 mg

Objective. To assess the dose prescription patterns for risperidone long-acting injectable (RLAI) in patients with schizophrenia who participated in the 6-month, open-label Switch to Risperidone Microspheres (StoRMi) trial. Methods. Clinically stable patients requiring a change in medication were converted to RLAI prescribed using clinically-appropriate doses, as determined by treating clinicians. RLAI 25 mg was recommended as the starting dose, although higher initiation doses were permitted if deemed necessary. RLAI was administered intramuscularly every 2 weeks, with dosage adjustments permitted, and continued for a total of 6 months. Efficacy outcomes included Positive and Negative Syndrome Scale (PANSS) and Clinical Global Impression-Severity (CGI-S). Treatment-emergent adverse events (AEs) were monitored. Results. A total of 1,849 patients were included. Modal dose was 25 mg for 52.9% of patients. At baseline, patients treated with lower RLAI doses were more likely to be female, have shorter disease duration, milder symptoms, and be using less polypharmacy. The strongest predictors that a patient would remain on 25 mg RLAI were baseline PANSS hallucinatory behaviour item score (odds ratio [OR]=0.78), baseline CGI-S score (OR=0.69), female gender (OR=1.56), and country of residence (P