Genotypic evolution of integrase and phenotypic sensitivity to raltegravir and elvitegravir in 3 patients failing on raltegravir-containing regimens.

Abbreviations: Time on RAL: duration of raltegravir–based therapy (months); *: raltegravir has been removed from therapy after month 6 for patient 1; RAL FC: raltegravir sensitivity fold-change; EVG FC: elvitegravir sensitivity fold-change; TDF: tenofovir diphospho fumarate; ETR: etravirine; DRV/r: darunavir boosted with ritonavir; ENF: enfuvirtide; FTC: emtricitabine; n.d.: not determined.