Symptomatic and Functional Remission with Paliperidone Palmitate 3-month and 6- month Formulations in Adult Patients with Schizophrenia: A 3-Year Analysis

Background: Paliperidone palmitate (PP), available as 1-month (PP1M), 3-month (PP3M) and 6-month (PP6M) formulations, has demonstrated efficacy in reducing the risk of relapse and delaying time to relapse in patients with schizophrenia. In this post hoc analysis, symptomatic and functional remission were assessed over a 3-year period in patients who transitioned from PP3M to PP6M (PP3M/PP6M) or continued PP6M (PP6M/PP6M) from a 1-year double-blind (DB) trial through a 2-year open-label extension (OLE) study.
Methods: Clinically stable adult patients with schizophrenia received PP3M or PP6M during a 1-year DB phase of a phase-3, randomized, noninferiority trial (NCT03345342). Patients who completed the DB-phase without relapse could choose to continue PP6M in a 2-year, single-arm OLE study (NCT04072575). Symptomatic remission: defined as Andreasen criteria (Positive and Negative Syndrome Scale symptoms [P1,G9,P3,P2,G5,N1,N4,N6] score of ≤3 for ≥6 months); functional remission: defined as Personal and Social Performance score >70.
Results: A total of 178 patients transitioned to PP6M (PP3M/PP6M=57) or continued PP6M (PP6M/PP6M=121) from the DB to the OLE study. Of these patients, at the DB endpoint, 47/57 (82.5%) PP3M/PP6M patients and 103/121 (85.1%) PP6M/PP6M patients achieved symptomatic remission, while 30/57 (52.6%) and 67/121 (55.4%) achieved functional remission, respectively. At the OLE endpoint (year 3), the rates of symptomatic (PP3M/PP6M:43/53 [81.1%]; PP6M/PP6M:87/101 [86.1%]) and functional remission (PP3M/PP6M:31/53 [58.5%]; PP6M/PP6M:60/102 [58.8%]) were sustained in both groups.
Conclusion: Patients who transitioned from PP3M to PP6M or continued PP6M treatment for up to 3 years had sustained functional and symptomatic remission, suggesting long-term efficacy of these treatments.