Safety and efficacy of once-daily didanosine, tenofovir and nevirapine as a simplification antiretroviral approach

Objective: To assess the efficacy and safety of a oncedaily antiretroviral regimen in HAART-experienced subjects with long-lasting viral suppression. Methods: One-hundred-and-sixty-nine patients with chronically suppressed viral load (limit of detection < 50 copies/ml) were recruited. Based on patient willingness to simplify treatment, 84 of them continued receiving their usual treatment (BID Group) and 85 switched to once-daily diclanosine/tenofovir/nevirapine (QD Group) in a non-randomized fashion. Results: At week 48, the proportion of patients with viral suppression in the QD and in the BID Group, respectively, was 97 vs 100% in the per-protocol analysis (P=0.497), and 76 vs 86% for the intention-to-treat analysis (P=0.176). Nevertheless, CD4 count decreased in the QD Group, with a mean decline of 95 cells/mm(3) (95% CI: 45-145). Twelve subjects in the OD Group (14%) discontinued treatment due to adverse events, mainly nevirapine-related hepatitis (6%). No significant differences regarding the rate of acute pancreatitis or peripheral neuropathy were observed between both groups. A significant improvement in the lipid profile was only seen in the QD Group. High levels of adherence were observed in both groups during follow-up, as well as a good quality of life. At week 48, a reduction in effort to take medication (P <= 0.001) and an increment in the satisfaction with the treatment (P < 0.001) was only seen in the QD group. No differences were observed in median nevirapine-trough levels between patients on twice-daily nevirapine at baseline (4820 ng/ml) and subjects in the QD Group (6090 ng/ml, P=0.30). Conclusion: Treatment simplification to a once-daily antiretroviral regimen based on didanosine, tenofovir and nevirapine may be a valid approach in HIV-infected subjects with long-lasting viral suppression. Combination of standard doses of didanosine and tenofovir may have contributed to the CD4 cell decline observed with this QD regimen.