For a randomized, double-blind (DB), parallel-group research, researchers sought to compare the effectiveness and safety of paliperidone palmitate 6-month (PP6M) formulation to paliperidone palmitate 3-month (PP3M) formulation in patients with schizophrenia. Following the screening, participants started an open-label (OL) maintenance phase and received 1 injectable cycle of paliperidone palmitate (PP1M; 100 or 150 mg eq.) or PP3M per month (350 or 525 mg eq.). In a 12-month DB phase, clinically stable patients were randomized (2:1) to receive PP6M (700 or 1000 mg eq., gluteal injections) or PP3M (350 or 525 mg eq.); two PP6M dosages (equivalent to PP1M and PP3M doses) were chosen.
Overall, 1,036 individuals were assessed, 838 entered the OL phase, and 702 (mean age: 40.8) were randomized (PP6M: 478; PP3M: 224), with 618 (88.0%) completing the DB phase (PP6M: 416 [87.0% ]; PP3M: 202 [90.2% ]). Relapse rates were 7.5% (n=36) for PP6M and 4.9% (n=11) for PP3M. The Kaplan-Meier estimate of the difference (95% CI) in the percentages of patients who remained relapse-free between treatment groups (PP6M PP3M) was 2.9% (6.8%, 1.1%), meeting noninferiority criteria (the 95% CI lower bound is greater than the prespecified noninferiority margin of 10%). The primary analysis was supported by secondary efficacy outcomes. The rates of treatment-emergent adverse events were comparable for PP6M (62.1%) and PP3M. (58.5%). There were no new safety issues. In patients with schizophrenia who had been satisfactorily treated with PP1M or PP3M, a twice-yearly dosage schedule of PP6M was non-inferior to that of PP3M in avoiding recurrence.
Reference:academic.oup.com/ijnp/article/25/3/238/6427395
