Healthcare Resource Utilization and Costs Among Patients With Schizophrenia Switching From Oral Risperidone/Paliperidone to Once-Monthly Paliperidone Palmitate: A Veterans Health Administration Claims Analysis

BACKGROUND: Schizophrenia is associated with high health care resource utilization and treatment costs. OBJECTIVE: This study compared treatment patterns, health care resource utilization, and medical costs before and after a switch from oral antipsychotic drug (risperidone or paliperidone [RIS/PALI]) therapy to the long-acting injectable once-monthly paliperidone palmitate (PP1M) in patients with schizophrenia. METHODS: Data for adult patients (aged ≥18 years) with at least 1 diagnosis of schizophrenia who initiated treatment with oral RIS/PALI ≥6 months before switching and had continuous health plan enrollment during the study period before and after the switch were extracted from the Veterans Health Administration database. Treatment patterns, health care resource utilization, and costs were compared between the period 6 or 12 months before and after switching directly from oral RIS/PALI to PP1M. RESULTS: The analysis included 676 and 493 patients in the 6-month and 12-month cohorts, respectively. Adherence to oral RIS/PALI during the 12 months preswitch was 11.0% and 22.1% as measured by proportion of days covered and medication possession ratio ≥80%, respectively. During the 12 months postswitch, adherence to PP1M was 27.0% and 35.9%, respectively. Among patients treated with oral RIS/PALI, from 12 months pre- to 12 months post-PP1M switch, fewer all-cause inpatient stays (2.2 vs 1.1, respectively; P < 0.05) and a shorter mean length of inpatient stay (28.1 and 14.0 days, respectively; P < 0.05) were observed. This pattern was similar for both the number of mental health– and schizophrenia-related inpatient stays and length of stay. Compared with 12 months pre-PP1M switch, significantly higher mean numbers of all-cause outpatient visits and pharmacy visits were observed at 12 months postswitch. In line with health care resource utilization findings, at 12 months pre- versus 12 months post-PP1M switch we observed decreases in all-cause inpatient stay costs ($41,886 vs $20,489; P < 0.05) and increases in outpatient visit costs ($22,005 vs $29,069; P < 0.05). Findings for the 6-month cohort followed a similar pattern. CONCLUSIONS: Post-PP1M switch, a decrease in total medical costs fully offset an increase in pharmacy costs, resulting in similar total costs. The findings suggest potential economic benefits of switching patients with schizophrenia from oral RIS/PALI to PP1M in the Veterans Health Administration.