Long-term efficacy and safety of paliperidone palmitate once-monthly in Chinese patients with recent-onset schizophrenia.

The subgroup analysis of a primary study (NCT01051531) evaluated the effect of long-term paliperidone palmitate once-monthly (PP1M) therapy in Chinese patients with recent-onset schizophrenia responding unsatisfactorily to previous oral antipsychotics. This 18-month, open-label study consisted of 3 phases - screening (7 days), treatment (18 months) and end-of-study/withdrawal visit. All enrolled patients (18-50 years) received PP1M: 150 mg eq. (day 1), 100 mg eq. (day 8) followed by a once-monthly flexible dose (50, 75, 100 or 150 mg eq.). Efficacy and safety were assessed. Among the 118 enrolled Chinese patients, 68 completed the treatment (mean age: 25.6 years; male: 54.7%). A clinically meaningful change from baseline to day 548 was observed in Positive and Negative Syndrome scale (primary endpoint, mean [SD]: -15.3 [20.76]), Personal and Social Performance scale (15.9 [19.65]), Clinician Global Impression-schizophrenia score (-1.2 [1.54]) and Medication Satisfaction Questionnaire score (0.9 [1.73]). Commonly reported treatment-emergent adverse events (TEAEs) included insomnia (13.9%), injection-site pain (13.9%), upper respiratory tract infection (13.0%), restlessness (13.0%) and akathisia (13.0%). Serious TEAEs were reported in 9.3% patients with schizophrenia being most common (6.5%) and one death (suicide) was observed. Efficacy of PP1M corroborate findings from earlier studies and no new safety concerns emerged in this Chinese subgroup of patients with schizophrenia.