[Temporal evolution of antiretroviral therapy (2017-2021): analysis of treatment change and its economic impact].

Objective: To analyze the modifications of antiretroviral therapy (ART) and their economic impact on daily clinical practice.

Methods: Observational, retrospective study of patients who started ART between 01/2017-12/2021 (follow-up until 12/2022). Variables collected: prescribed ART, duration, the reason for the change, and treatment costs.

Results: A total of 280 patients initiated ART therapy. The median durability of 1st line was: 19.9 months in 2017 (95%CI 13.9-25.9), 12.2 months in 2018 (95%CI 4.7-19.7), 27.4 months in 2019 (95%CI 6.8-48.1) and the median was not reached for the years 2020 and 2021 (p<0.001). Triple therapy with protease inhibitors was changed in 63.8% (81/127) of cases, followed by integrase inhibitors 52.1% (159/305), while dual therapy (DTG/3TC) only in 8.3% (7/84). The main cause of discontinuation was simplification/optimization 47.5% (124/261), followed by adverse effects 21.8% (57/261), with 2017 being the only year where simplification/optimization was at the same level as adverse effects. The economic impact of ART changes resulted in an average cost reduction of 34.0€ [-391.4 to +431.4] per month per patient. The year 2019 stands out as the only year where these changes were associated with an increase in mean additional cost (23.4€ [-358.3 to +431.4]).

Conclusions: Optimization/simplification accounts for almost half of the reasons for TAR change, with an economic impact that, despite the inflection point of 2019, each year manages to exceed the previous one, achieving a progressive cost reduction maintained over time.