Cost-Minimisation Analysis of Paliperidone Palmitate Long-Acting Treatment versus Risperidone Long-Acting Treatment for Schizophrenia in Spain.

Background and Objective: Long-acting formulations for paliperidone (PPLAT) and risperidone (RLAT) are effective second-generation antipsychotics. This study aimed to compare treatment costs between PPLAT and RLAT in schizophrenia patients.
Methods: A cost-minimization analysis was performed from the perspective of the Spanish National Healthcare System (NHS), in line with the approach accepted by the Scottish Medicine Consortium evaluation. Only direct health costs (€, 2015) were included, i.e. medication (including oral antipsychotic drug supplementation), hospitalization and cost of administration in the community. Two time horizons were used: 1 year (to compare initiation treatment) and 2 years (to compare maintenance treatment). Base-case considered the following assumptions: setting for treatment initiation (50 % hospital and 50 % community); 50 % of patients initiating from a long-acting treatment and 50 % from an oral antipsychotic; no reduction in the length of stay. One-way sensitivity analyses (SA) were performed.
Results: The estimated costs/patient were €7698 (PPLAT) and €8168 (RLAT) for the first year, and €4314 (PPLAT) and €5003 (RLAT) for the second year. Cost savings related to PPLAT therapy were €470 and €689 for first and second year, respectively. SA results confirmed the robustness of the model results, even in the most conservative scenarios: (1) if 100 % of patients initiate treatment in hospital, the savings could be €454 per patient; (2) if 100 % of patients initiate treatment from an oral antipsychotic, the savings could be €277 per patient/year; and (3) if PPLAT could not reduce the length of stay by approximately one-third, as some studies indicate, the savings could be €470 per patient/year.
Conclusions: The use of PPLAT instead of RLAT could be a cost-saving strategy for the Spanish NHS.