RESUMEN
OBJECTIVE: To compare the antiviral activity of once-daily didanosine (ddI) and twice-daily ddI in combination with stavudine (d4T). DESIGN: Randomized, double-blind, multicenter study. SETTING: Twenty-one sites in the United States. PATIENTS: Eighty-seven antiretroviral-naive, HIV-1-infected adults with baseline plasma HIV RNA counts of > or = 10,000 copies/ml and CD4 cell counts of > or = 100 cells/mm3 started study therapy. INTERVENTIONS: Patients received once-daily ddI or twice-daily ddI, each combined with twice-daily d4T. MAIN OUTCOME MEASURES: Plasma HIV-1 RNA levels, CD4 cell counts, and adverse events were regularly monitored. The primary efficacy analysis used was the time-averaged difference (TAD) between treatment regimens in change from baseline plasma HIV-1 RNA levels over the first 12 weeks of therapy. RESULTS: At week 12, median log10 HIV-1 RNA changes were -1.83 log10 copies/ml in the once-daily ddI/d4T group and -1.80 log10 copies/ml in the twice-daily ddI/d4T group, and 18 out of 44 patients (41%) and 17 out of 43 patients (40%), respectively, had HIV-1 RNA levels below 400 copies/ml. Similar results were seen at week 24. The TAD between the two treatment groups (once-daily ddI/d4T minus twice-daily ddI/d4T) in change from baseline plasma HIV RNA levels over the first 12 weeks was 0.14 log10 copies/ml (95% CI: -0.11, 0.40). At week 12, subjects averaged an increase in CD4 cell count of over 140 cells/mm3. The TAD between the two treatment groups in change from baseline CD4 cell counts over the first 12 weeks was 2 cells/mm3 (95% CI: -40, 45). CONCLUSION: Once-daily ddI plus d4T and twice-daily ddI plus d4T were similarly effective in reducing plasma HIV-1 RNA levels and increasing CD4 cell counts over 12-24 weeks of therapy.