Evaluating Cost-Effectiveness of Antiretroviral Therapy over Time: A Cohort and Cost-Effectiveness Study.

Objective: To estimate the costs and cost-effectiveness of introducing highly active antiretroviral therapy (HAART) in Denmark based on real-world evidence for the three treatment eras pre-HAART (1985-1995), early HAART (1996-2005), and late HAART (2006-2017).

Methods: We performed a cohort study using Danish clinical and administrative registries to estimate costs, quality-adjusted life-years (QALYs), and life-years (LY) gained per person living with human immunodeficiency virus (PLHIV) in three treatment eras. The study utilized Markov modeling for a health economic evaluation, which summarized inputs from real-world evidence and estimated the cost-effectiveness in 2017 prices of the introduction of HAART in Denmark. We performed deterministic and probabilistic sensitivity analyses to assess the robustness of the results.

Results: The total annual costs per PLHIV increased with the introduction of HAART for the index year but decreased in the incremental years and the last year of life. The total lifetime discounted (and undiscounted) cost for an average PLHIV was €91,010 (€128,981) in pre-HAART, €103,130 (€199,062) in early HAART, and €126,317 (€254,964) in late HAART. The estimated incremental cost-effectiveness ratios showed that early HAART was cost-effective compared with pre-HAART with an incremental cost-effectiveness ratio (ICER) of €1378 per QALY, and that late HAART was cost-effective compared with early HAART with an ICER of €7385 per QALY. Sensitivity analyses confirmed cost-effectiveness in all scenarios.

Conclusions: The introduction and implementation of HAART in Danish healthcare was cost-effective, and in some scenarios, even disruptive, i.e., led to both cheaper and more effective care of PLHIV.