Efficacy and safety of risperidone long-acting injectable in stable psychotic patients previously treated with oral risperidone.

This subgroup analysis of symptomatically stable patients with schizophrenia or other psychotic disorders in the StoRMi trial determined the efficacy and tolerability of risperidone long-acting injectable in patients changed from oral risperidone monotherapy. Risperidone long-acting injectable was administered open-label (dosage 25/37.5/50 mg every 2 weeks for 6 months). In total, 568 patients (60% men, mean age 36-40 years) were included and grouped according to pre-trial oral risperidone dosage (56°/o ≤, 4 mg; 30% >4 to ≤ 6 mg; 14% >6 mg). Most patients (71-85% across groups) were diagnosed with schizophrenia. At endpoint, risperidone long-acting injectable dosages partly correlated with the previous oral risperidone dosage. Some patients previously on high dosages of oral risperidone responded well to lower risperidone long-acting injectable dosages. Efficacy significantly improved from baseline to endpoint in all groups; total Positive and Negative Syndrome Scale score improved by ≥ 20% in 39% of all patients. Clinical global impression symptoms, global assessment of function scores, and the SF-36 mental component score significantly improved in all groups. Hospitalizations were reduced by 74-80%. Extrapyramidal symptom rating scale scores were significantly better at endpoint (P ≤ 0.001). These results indicate that further improvement in symptom control can be seen after a change to risperidone long-acting injectable in clinically stable patients previously treated with oral risperidone.