Etravirine is a next generation nonnucleoside reverse transcriptase inhibitor with activity against nonnucleoside reverse transcriptase inhibitor resistant HIV-1 virus. Susceptibility and virological response to etravirine is dependent on the type and number of nonnucleoside reverse transcriptase inhibitor resistance-associated mutations. We examined the predicted susceptibility of etravirine in patients experiencing virological failure secondary to nonnucleoside reverse transcriptase inhibitor resistance in our patient cohort.