Virus, som var resistente over for zidovudin, zalcitabin, didanosin og NNRTIs, beholdt deres følsomhed over for emtricitabin (IC50=0, 002 µmol/ l- 0, 08 µmol/ l).
Viruses resistant to zidovudine, zalcitabine, didanosine and NNRTIs retained their sensitivity to emtricitabine (IC50=0.002 µmol/ l to 0.08 µmol/ l).