Pharmacoeconomic assessment of antipsychotic treatment in outpatients with schizophrenia

Abstract

The aim: to provide a comprehensive pharmacoeconomic evaluation of the antipsychotic maintenance therapy in outpatients diagnosed with schizophrenia. Materials and methods. The analysis was conducted in two mutually complementary stages: an epidemiological study on the management of outpatients with schizophrenia, and a subsequent pharmacoeconomic modeling. Two medical technologies were evaluated and compared: treatment with classical antipsychotics (CA) and treatment with atypical antipsychotics (AA). Based on a retrospective study of patients’ medical records, we selected the parameters to be used in the clinical and economic analysis of these treatments. Direct and indirect costs were taken into account to perform the cost-effectiveness analysis, incremental analysis, and «budget impact» analysis. Results . We determined the costs of managing of outpatients with schizophrenia in relation to the health budget and in relation to the social burdens; the appropriateness and effectiveness of the present costs was analyzed for different time intervals – 6, 12 and 24 months. As shown, the treatment strategies involving AA were more budget-consumptive than the CA treatments. If the treatments were switched to the reproduced AA (up to 100% replacement of reference medications), the costs would remain to be higher than those for the CA. The «costeffectiveness » analysis related to «the proportion of stable patients» for the horizons of 6 and 12 months indicated that the reproduced AA would be more economically effective than the CA. However, when the observation period is increased to 24 months, this economic advantage of AA disappears, and the CA drugs have a lower CER instead. For the «number of hospitalization-free days per year», the use of AA was more cost-effective only versus the 100% use of reproduced AA at the simulated horizon of 12 months. When estimated for the use of 100% reference AA or the combined reference + reproduced AA, the treatment with CA remained more economically effective, regardless of the simulated period. Conclusion . The pharmacoeconomic simulation of the antipsychotic therapy in outpatients with schizophrenia suggests the ways of treatment optimization. Among them, using AA for the treatment of at least 15.6% of patients (those who are employed); keeping the ≥60% use of CA to ensure the optimal resource-saving effect of the treatment; using reproduced AA at the level of ≥70% (instead of the reference AA similar in efficacy and safety) to keep the treatment economically justified.