Comparison of Relapse Prevention with 3 Different Paliperidone Formulations in Patients with Schizophrenia Continuing versus Discontinuing Active Antipsychotic Treatment: A Post-Hoc Analysis of 3 Similarly Designed Randomized Studies.

BACKGROUND: Sudden discontinuation from antipsychotic treatment is a common occurrence in patients with schizophrenia. Lower rates of relapse could be expected for patients discontinuing treatment from longer-acting formulations vs their shorter-acting equivalents. OBJECTIVE: To compare relapse rates and time-to-relapse between the active (analogous to adherent patients) and placebo (analogous to non-adherent patients in the real-world) arms of three different formulations of paliperidone (oral paliperidone extended release [paliperidone ER], paliperidone palmitate once monthly [PP1M], and paliperidone palmitate three monthly [PP3M] long-acting injectables). METHODS: Data from three similarly designed, randomized relapse prevention studies in adult patients with schizophrenia were analyzed. RESULTS: In total, 922 patients were included (active treatment: 473, placebo: 449). Lowest percentage of patients experienced relapse with PP3M PP1M (172 days [134-222 days])> paliperidone ER (58 days [42-114 days]) and was "not-estimable" in the active treatment group due to low relapse rates. Hazard ratios (HR) of the three paliperidone formulations relative to their respective placebos were PP3M ([HR: 3.81; 95% CI: 2.08, 6.99; P< 0.0001]> PP1M [HR: 3.60; 95% CI: 2.45, 5.28; P<0.0001]> paliperidone ER [HR: 2.83; 95% CI: 1.73, 4.63; P<0.001]). CONCLUSION: The lower percentage of relapse during active treatment and longer time to relapse after discontinuing active treatment with longer-duration antipsychotic formulations suggests the benefit of longer-acting over shorter-acting formulations, especially in patients susceptible to poor adherence.Clinical trial registration: paliperidone ER (NCT00086320), PP1M (NCT00111189), and PP3M (NCT01529515).

Efficacy and safety of paliperidone palmitate 3-month formulation in Latin American patients with schizophrenia: A subgroup analysis of data from two large phase 3 randomized, double-blind studies

Objective: To analyze the efficacy and safety of paliperidone palmitate 3-monthly (PP3M) in Latin American patients with schizophrenia vs. rest-of-world (ROW). Methods: We analyzed data from two multinational, double-blind (DB), randomized, controlled phase 3 studies including patients with schizophrenia (DSM-IV-TR) previously stabilized on PP1M/PP3M (open-label [OL] phase). Patients were randomized to PP3M or PP1M (noninferiority study A) and PP3M or placebo (study B) in DB phase. The subgroup analysis included Latin American (Argentina, Brazil, Colombia, Mexico) patients. Primary efficacy endpoints were relapse-free rates (study A) and time-to-relapse (study B). Results: In study A, 63/71 (88.7%) and in study B 38/43 (88.4%) Latin American patients completed the DB phase. In study A, relapse-free percentage was similar in Latin America (PP3M: 97%, PP1M: 100%) and ROW (PP3M: 91%, PP1M: 89%). In study B, median time-to-relapse was not estimable in the Latin American subgroup for either placebo or PP3M groups, nor for the ROW PP3M group; the median time-to-relapse in the ROW placebo group was 395 days. Caregiver burden improved in patients switching from oral antipsychotics (OL baseline) to PP3M/PP1M in DB phase (Involvement Evaluation Questionnaire score mean ± SD change, -9.4±15.16; p < 0.001). Treatment emergent adverse events with PP3M during DB phase were similar in Latin America (study A: 24/34 [70.6%]; study B: 15/21 [71.4%]) and ROW (study A: 318/470 [67.7%]; study B: 84/139 [60.4%]) subgroups. Conclusion: PP3M was efficacious and showed no new safety concerns in patients with schizophrenia from Latin America, corroborating ROW findings. Clinical trial registration: NCT01515423, NCT01529515

Efficacy and safety of paliperidone palmitate three-monthly formulation in East Asian patients with schizophrenia: subgroup analysis of a global, randomized, double-blind, Phase III, noninferiority study.

OBJECTIVE: To demonstrate the efficacy and safety of paliperidone palmitate three-monthly (PP3M) formulation in an East Asian population with schizophrenia by subgroup analysis of a double-blind (DB), multicenter, noninferiority study. PATIENTS AND METHODS: Of 1,429 patients who entered the open-label (OL) phase, 510 were East Asian (China: 296 [58%], Japan: 175 [34%], South Korea: 19 [4%] and Taiwan: 20 [4%]). In the 17-week OL phase, patients received paliperidone palmitate once-monthly (PP1M) formulation on day 1 (150 mg eq.), day 8 (100 mg eq.) and once-monthly thereafter (50-150 mg eq., flexible). Following the OL phase, patients (n=344 East Asian) entered DB phase and were randomized (1:1) to PP1M (n=174) or PP3M (n=170). Primary efficacy endpoint was the percentage of patients who remained relapse free at the end of the 48-week DB phase, using Kaplan-Meier cumulative survival estimate. Secondary efficacy endpoints included change from DB baseline to endpoint in Positive and Negative Syndrome Scale, Clinical Global Impression Severity, Personal and Social Performance scores and symptomatic remission. Additional assessments included caregiver burden and safety. RESULTS: A total of 285/344 (83%) randomized East Asian patients completed the DB phase. The percentage of patients who had a relapse event was similar on comparing PP3M (17 [10.2%]) to PP1M (20 [11.8%]), and also for Japan (PP3M: 9 [17.6%], PP1M: 13 [23.2%]) and China (PP3M: 6 [5.9%], PP1M: 7 [6.9%]). Mean change from baseline in secondary efficacy parameters was similar to the global population, regardless of treatment. Symptomatic remission was attained by 50% of the treated patients. Caregiver burden was significantly reduced (P<0.001) following treatment with PP3M/PP1M. Frequency of treatment-emergent adverse events in PP3M group during DB phase was greater in the East Asian subgroup (81%) than the global population (68%) and was higher in Japan (92%) than China (75%). CONCLUSION: Results suggest that PP3M is efficacious in the East Asian subgroup. Although treatment-emergent adverse events were slightly higher in the East Asian subgroup versus the global population, no new safety signals were identified.