An Immunological Comparison of Third Companion in Advanced Drug-Naive HIV-Infected Patients

AbstractAn immunological comparison of three different third companions (abacavir [ABC], efavirenz [EFV], ritonavir-boosted indinavir [IDVr]) on a backbone of either zidovudine plus didanosine (AZT/ddI) or zidovudine plus lamivudine (AZT/3TC) was performed in 76 HIV-infected, advanced-naive patients. Baseline median CD4 count and viremia were 217/μL and 238,301 copies/mL, respectively. Immunologic parameters were measured at baseline and after months of therapy. By the end of the study, 36 patients (mostly in the protease inhibitor [PI]-containing arms) had dropped out of the study; 22/36 cases of drop out were due to tolerability issues. All regimens resulted in increases in CD4 counts, with the most solid changes seen in patients using ABC as a third companion. Median HIV plasma viremia at month 12 was <50 copies/mL, and viremia was undetectable in 26/38 patients (68%). At the end of the study period, HIV antigen- and mitogen-stimulated proliferation overall was better in patients using either of the PI...