Early virological failure in treatment-naive HIV-infected adults receiving didanosine and tenofovir plus efavirenz or nevirapine.

A 50% rate of early virological failure associated with the selection of resistance mutations was seen in a group of 14 antiretroviral-naive adults who initiated highly active antiretroviral therapy with tenofovir and didanosine plus efavirenz or nevirapine. At month 6, the mutations detected were K65R, L74V, L100I, K103N/R/T, Y181C and G190E/Q/S. These results argue against the use of tenofovir plus didanosine in HIV-infected antiretroviral-naive adults even when the third drug is a non-nucleoside reverse transcriptase inhibitor.