OBJECTIVES : Rapid HIV treatment initiation on the day of diagnosis in the absence of laboratory test data, known as immediate test and treat (T&T), is being increasingly employed as a treatment strategy in some communities and states. The 2-drug regimen of DTG/3TC is currently under regulatory review as a comparable alternative to traditional 3-drug regimens (3DRs). This analysis aims to provide an early estimate of the cost-effectiveness of DTG/3TC compared to three other commonly used T&T regimens: DTG+tenofovir alafenamide/emtricitabine (TAF/FTC); bictegravir (BIC)/TAF/FTC; and boosted darunavir (DRV/c)+TAF/FTC.

METHODS : A previously published hybrid decision tree and Markov cohort state transition model was utilized to estimate outcomes in treatment-naïve HIV-1 infected subjects over a lifetime horizon. Efficacy and safety assumptions for each regimen were derived from a network meta-analysis based on published clinical trials. Patients who may not be optimal for DTG/3TC, as defined by a baseline HIV-1 viral load >500k copies/mL, active hepatitis B, or M184V resistance, were assumed to switch therapies after the first month of treatment based on the receipt of laboratory test results; the likelihood of switching was derived from US population estimates. Monthly wholesale acquisition costs were assumed for each regimen. Modelled outcomes included: quality-adjusted-life-years (QALYs), total costs, and incremental cost-effectiveness ratios.

RESULTS : Few patients (~8.3%) required a switch from DTG/3TC within the first month of T&T. Across all comparisons, DTG/3TC was estimated to be dominant or highly cost-effective, with incremental QALYs of -0.037 to 0.038 and cost-savings ranging from $41,212 to $71,029. In univariate sensitivity analyses, drivers of cost-effectiveness were the proportion of patients requiring a switch in treatment, modelled time horizon, discounting, acquisition costs and treatment duration without response.

CONCLUSIONS : DTG/3TC has demonstrated non-inferior efficacy to conventional 3DRs and is highly likely to represent a cost-effective treatment option for treatment-naïve HIV-1 infected patients initiated on treatment through a T&T framework.