A recent study showing that a two-drug antiretroviral (ARV) regimen maintains viral suppression as well as a standard three-drug cocktail throws weight behind research into long-acting ARVs. 
Nearly 250 participants in this Phase IIb trial were randomly assigned to begin taking two nucleoside/nucleotide reverse transcriptase inhibitors (NRTIs) plus either the integrase inhibitor cabotegravir or Sustiva (efavirenz). 
After 24 weeks, the 87 percent (160 people) of those on cabotegravir who had stable viral suppression swapped Edurant (rilpivirine) for their NRTIs. Forty-seven people taking Sustiva stayed on their same regimen into this next phase of the trial. 
Viral suppression rates were similar between the two groups 96 weeks into the study. Meanwhile, research is under way into long-acting, injectable versions of cabotegravir and Edurant that could be taken only every four or eight weeks.