OBJECTIVES: The aim of the study was to assess the cost-effectiveness of the four regimens studied in the AIDS Clinical Trials Group (ACTG) 5202 clinical trial, tenofovir/emtricitabine (TDF/FTC) or abacavir/lamivudine (ABC/3TC) in combination with efavirenz (EFV) or atazanavir/ritonavir (ATV/r), for treatment-naïve adults with HIV-1 infection in the UK.
METHODS: A Markov model with six health states based on CD4 cell count ranges was developed to predict long-term costs and health outcomes for individuals on first-line therapy. Head-to-head efficacy data comparing TDF/FTC + EFV, TDF/FTC + ATV/r, ABC/3TC + EFV, and ABC/3TC + ATV/r were obtained from ACTG 5202 for up to 192 weeks. Antiretroviral drug costs were based on current list prices. Other medical costs (2013 UK pounds sterling), utility values, and mortality rates were obtained from published sources. Base-case, sensitivity, and subgroup analyses (by baseline viral load) were conducted.
RESULTS: Individuals using TDF/FTC-based regimens were predicted to remain on first-line therapy longer and accrue more quality-adjusted life-years (QALYs) than individuals using ABC/3TC-based regimens. At a willingness-to-pay threshold of £30 000 per QALY gained, TDF/FTC-based regimens were predicted to be cost-effective compared with ABC/3TC-based regimens, with incremental cost-effectiveness ratios of £23 355 for TDF/FTC + EFV vs. ABC/3TC + EFV and £23 785 for TDF/FTC + ATV/r vs. ABC/3TC + ATV/r. Results were generally robust in subgroup, sensitivity, and scenario analyses.
CONCLUSIONS: In an analysis of the regimens studied in ACTG 5202 for treatment-naïve adults with HIV-1 infection in the UK, TDF/FTC-based regimens yielded more favourable health outcomes and were generally predicted to be cost-effective compared with ABC/3TC-based regimens. These results confirm that TDF/FTC-based regimens are not only clinically effective but also cost-effective.
