Generic-based antiretroviral therapy may be cost-effective, mathematical simulation model indicates

Three-pill generic-based antiretroviral therapy (ART) is cost-effective and could offer cost savings compared with a branded single-pill regimen, a new study indicates.

Current U.S. guidelines for first-line treatment of HIV infection recommend a once-daily regimen of a branded pill containing efavirenz, emtricitabine, and tenofovir. However, because a generic version of efavirenz is expected to be approved soon, researchers performed a mathematical simulation to compare the clinical effect, costs and cost-effectiveness of standard therapy and a once-daily three-pill regimen containing generic efavirenz, generic lamivudine and tenofovir. The latter regimen would be less expensive but could decrease adherence and virologic suppression.

Three regimens were compared: no ART, three-pill generic-based ART (generic efavirenz and lamivudine plus branded tenofovir) and one-pill branded ART (efavirenz, emtricitabine and tenofovir). The main outcome measures were quality-adjusted life expectancy, costs, and incremental cost-effectiveness ratios (ICERs) in dollars per quality-adjusted life-year (QALY). The hypothetical cohort entered into the mathematical model was similar to patients newly diagnosed with HIV infection in the U.S. in 2009. Eighty-four percent were assumed to be men, and mean CD4 cell count at presentation was assumed to be 0.317 × 10⁹ cells/L. Study results were published in the Jan. 15 Annals of Internal Medicine.

Generic-based ART had an ICER of $21,000/QALY compared with no ART. Branded ART versus generic-based ART increased lifetime costs by $42,500 and increased survival gains per person by 0.37/QALY, leading to an ICER of $114,800/QALY. The authors estimated that if all eligible U.S. patients started or switched to generic-based ART, $920 million would be saved in the first year of treatment. Branded ART consistently showed an ICER greater than $100,000/QALY.

The authors noted that the efficacy of and price reduction with generic drugs are unknown, and that their estimates were conservative. They also noted that the tradeoff between cost savings and health benefits may be controversial and that higher willingness-to-pay thresholds could make the higher cost of branded regimens more acceptable. However, they concluded that the generic-based regimen offered substantial cost savings compared with the branded regimen, although it was slightly less effective clinically. “Starting or switching to generic-based regimens would initially yield annual savings approaching $1 billion for programs that fund HIV treatment in the United States,” the authors wrote.

The author of an accompanying editorial pointed out that recent changes related to the Affordable Care Act may make generic antiretroviral drugs more attractive to some stakeholders. “HIV advocates and caregivers might more readily embrace generic antiretrovirals if…the savings were diverted to address other funding needs within the field of HIV medicine,” he wrote. Regardless, he concluded, “The era of generic antiretrovirals in the United States has come.”