Efficacy and safety of abacavir plus lamivudine versus didanosine plus stavudine when combined with a protease inhibitor, a nonnucleoside reverse transcriptase inhibitor, or both in HIV-1 positive antiretroviral-naive persons.

Purpose: The combination of abacavir + lamivudine (ABC+3TC) versus didanosine + stavudine (ddl+d4T), each combined with other classes of antiretrovirals (ARVs) in ARV-naive patients, was compared for the combined endpoint of time to plasma HIV RNA > 50 copies/mL (at or after the 8-month visit) or death (primary endpoint) in a nested substudy of an ongoing multicenter randomized trial. Method: The substudy enrolled 182 patients; mean HIV RNA and CD4+ cell counts at baseline were 5.1 log(10) copies/mL and 212 cells/mm(3), respectively. Results: After a median follow-up of 28 months, rates of primary endpoint were 57.2 and 67.8 per 100 person-years for the ABC+3TC and ddl+d4T groups (hazard ratio [HR] = 0.81, 95% confidence interval [CI] 0.58-1.14, p = .23). Conclusion: There was a trend for treatments containing ABC+3TC to be better than treatments containing ddI+d4T with respect to HIV RNA decreases, CD4+ cell count increases, and tolerability.