Objective: Conduct a cost effectiveness analysis for the Paliperidone palmitate Research In Demonstrating Effectiveness (PRIDE) trial.
Research design and methods: PRIDE was a 15 month, prospective, randomized, open-label study in which once monthly paliperidone palmitate significantly delayed the time to first treatment failure (healthcare or criminal justice system [HC/CJS] events) versus oral antipsychotics in recently incarcerated adults with schizophrenia. The present analysis used a state government perspective and HC/CJS event data that were collected on a resource use questionnaire (RUQ) every 3 months.
Main outcome measures: Since cost information was not collected in the trial, cost estimates from published literature and an analysis of multistate Medicaid data for CJS and HC events, respectively, were applied to RUQ event data. Effectiveness and costs were adjusted to 456 days (trial duration). Incremental cost effectiveness was calculated as the adjusted cost difference divided by the adjusted effectiveness difference.
Results: Adjusted costs (in US dollars) in the paliperidone palmitate group (n = 198) and the oral antipsychotic group (n = 193), respectively, were: non-drug costs $22,331 and $25,027; drug costs $18,592 and $7833; and total costs $40,923 and $32,860. Adjusted effectiveness differences and corresponding incremental cost effectiveness per event avoided (in parentheses) for paliperidone palmitate versus oral antipsychotics were as follows: 0.33 fewer CJS events ($24,409), 0.13 fewer psychiatric hospitalizations ($60,484), 0.46 fewer psychiatric hospitalizations or CJS events combined ($17,391), and 0.30 fewer incarcerations ($26,754).
Conclusions: Costs for HC/CJS events avoided offset 25% of the greater drug cost for the paliperidone palmitate versus oral antipsychotic treatment group in this vulnerable population. Use of a recall-dependent RUQ for event rates and cost estimates instead of actual costs are potential limitations and may make the results conservative from a state government perspective. Indirect costs are likely to be substantial for this population, but were not considered in the analysis.
Keywords: Cost effectiveness; Criminal justice system; Oral antipsychotics; Paliperidone palmitate; Schizophrenia.