Objective: Based on the short-term results of the AIDS Clinical Trials Group (ACTG) A5095 trial, zidovudine (ZDV)/lamivudine (3TC)/abacavir (ABC) is no longer recommended as a first-line antiretroviral regimen. Data on the efficacy of this triple nucleoside reverse transcriptase inhibitor (NRTI) combination compared with the gold-standard nonnucleoside reverse transcriptase inhibitor (NNRTI) regimen could provide important information.
Methods: Patients were selected from three prospective cohorts of patients who received first-line therapy with ZDV/3TC plus an NNRTI or ABC, started after January 1998. Immunovirological changes and the proportion of treatment discontinuations were compared between groups.
Results: Of the 380 patients, 190 started on ABC [the triple-NRTI group (3N)] and 190 on NNRTI. At baseline, there was no statistical difference between the NNRTI and 3N groups for age (mean=38 years), sex (66% male) or CD4 cell count (mean=305 cells/muL). Mean baseline plasma HIV-1 viral load (pVL) was higher in the 3N group (4.6 vs. 4.3 log10 HIV-1 RNA copies/mL: P<0.01). Lower and higher estimates of median pVL decrease at month 24 were 2.05 and 4.76 log10 copies/mL in the 3N group, and 1.73 and 4.31 log10 copies/mL in the NNRTI group (not significant). CD4 cell count evolution did not differ between groups. Treatment discontinuation occurred in 45% vs. 44% of patients in the NNRTI and 3N groups, respectively, after median durations of 9 and 4 months, respectively (P=0.02).
Conclusions: In this prospective cohort, 3N and NNRTI regimens as first-line therapy produced similar immunovirological responses.