Background: We assessed a once-daily combination to simplify therapy in patients infected with human immunodeficiency virus type 1 (HIV-1).
Methods: A total of 355 adults with plasma HIV-1 RNA levels <400 copies/mL were randomly assigned to either switch to once-daily emtricitabine, didanosine, and efavirenz (n=178) or maintain their protease inhibitor (PI)-based regimens (n=177). The primary end point was sustained suppression of plasma HIV-1 RNA levels to <400 copies/mL.
Results: At week 48, the proportion of patients meeting the end point was 87.6% in the PI group and 90.5% in the once-daily group, with a treatment difference of -2.9% (upper bound of the 1-tailed 95% confidence interval, 2.6%). The proportion of patients with HIV-1 RNA levels <50 copies/mL was higher in the once-daily group (87%) than in the PI group (79%) (P<.05). Resistance mutations to efavirenz and emtricitabine were detected in all patients in the once-daily group who experienced virologic failure while receiving study medication. The proportion of patients discontinuing study medication because of adverse events was similar between the once-daily group (9%) and the PI group (10%) (P=.8).
Conclusions: Substituting a convenient once-daily combination of emtricitabine, didanosine, and efavirenz for a PI-based regimen was well tolerated and associated with sustained virologic suppression.