Changes in schizophrenia-related hospitalization and ER use among patients receiving paliperidone palmitate: results from a clinical trial with a 52-week open-label extension (OLE)

Abstract

Background:Schizophrenia affects ∼1.1% of the United States population, resulting in substantial direct, indirect and societal costs.Objective:To evaluate hospitalization rates associated with use of paliperidone palmitate (PP).Methods:Data were from a variable-duration double-blind (DB), randomized, relapse-prevention comparison (NCT00111189) of PP vs. placebo (Pbo), followed by a 1-year open-label extension (OLE). Between-phase change in schizophrenia-related hospitalizations was evaluated using data from an investigator-completed questionnaire. Change in hospitalizations using patients before enrollment who participated in the OLE phase was also analyzed. Poisson regression was used to evaluate changes in incidence density within exposure category and by schizophrenia duration.Results:A total of 160 patients in the PP-PP group and 153 in the Pbo-PP group from the DB to the OLE phase were included. Mean age (standard deviation [SD]), gender, and duration of schizophrenia were similar at the start of the DB phase (Pbo: 38.5 years [10.6], 51.0% male, 68.0% ≥5 years’ duration; PP: 37.3 years [11.4] (p = 0.342); 51.9% male (p = 0.874); 70.0% ≥5 years’ duration (p = 0.698), respectively. From the DB to the end of the OLE phase, the number of hospitalizations per person-year for patients treated during the DB phase with Pbo significantly declined from 0.27 to 0.06 (78% reduction; p = 0.005). A statistically nonsignificant difference was observed for PP patients treated during the DB phase with PP (0.11–0.04; 63.6% reduction; p = 0.076), compared with the OLE phase. Change from before enrollment to the end of the OLE phase (n = 381) produced similar results (0.35–0.04; 88.6% reduction; p < 0.001). Patients who enroll in a clinical trial may be different from the general population and this may affect the generalizability of results.Conclusion:From the double-blind to the open-label phase and from prior to the trial until the end of the open-label phase, hospitalizations significantly decreased for patients with schizophrenia treated with PP.