Hos virologisk stabile, behandlingserfarne voksne viste det sig, at emtricitabin, i kombination med en NRTI (enten stavudin eller zidovudin) og proteasehæmmer (PI) eller en NNRTI ikke var mindre effektiv end lamivudin med hensyn til procentdelen af responderende (< 400 kopier/ ml) i 48 uger (77% emtricitabin, 82% lamivudin).
In virologically stable treatment-experienced adults, emtricitabine, in combination with an NRTI (either stavudine or zidovudine) and a protease inhibitor (PI) or an NNRTI was shown to be non-inferior to lamivudine with respect to the proportion of responders (< 400 copies/ ml) through 48 weeks (77% emtricitabine, 82% lamivudine).