Early Treatment in HIV Patients: A Cost-Utility Analysis from the Italian Perspective

Abstract

Background and objective: Highly active antiretroviral therapy (HAART) has modified the clinical course of human immunodeficiency virus (HIV) infection, reducing the rate of disease progression, the incidence of opportunistic infections and mortality. Several recent studies show early antiretroviral therapy reduces the risk of AIDS and HIV-related disease. The aim of this study was to perform an economic analysis to estimate the cost-utility of early antiretroviral therapy in Italy for managing HIV-infected patients.

Methods: The incremental cost-utility analysis was carried out to quantify the benefits of the early-treatment approach in HIV subjects. A Markov simulation model including direct costs and health outcomes was developed from a third-party (Italian National Healthcare Service) payer's perspective for four CD4 strata. 5000 Monte Carlo simulations were performed on two distinct scenarios: Standard of care (SoC) in which 30% of patients started HAART with a CD4 count ≥500 cells/mm(3) versus the early-treatment scenario (ETS), where the number of patients starting HAART with a CD4 count ≥500 cells/mm(3) increased to 70%. A systematic literature review was carried out to identify epidemiological and economic data, which were subsequently used to inform the model. In addition, a one-way probabilistic sensitivity analysis was performed in order to measure the relationship between the effectiveness of the treatments and the number of patients to undergo early treatment.

Results: The model shows, in terms of the incremental cost-effectiveness ratio (ICER) per quality-adjusted life years (QALY) gained, that early treatment appeared to be the most cost-effective option compared to SoC (ICER = €13,625) over a time horizon of 10 years. The cost effectiveness of ETS is more sustainable as it extends the time horizon analysis (ICER = €7526 per QALY to 20 years and €8382 per QALY to 30 years). The one-way sensitivity analysis on the main variables confirmed the robustness of the model for the early-treatment approach.

Conclusion: Our model represents a tool for policy makers and health-care professionals to provide information on the cost effectiveness of the early-treatment approach in HIV-infected patients in Italy. Starting HAART earlier keeps HIV-infected patients in better health and reduces the incidence of AIDS- and non-AIDS-related events, generating a gain in terms of both patients' health and correct resource allocation.