To prospectively determine the virologic impact of switching treatment-experienced HIV-infected patients with virologic failure to a salvage regimen with or without a 12 week STI prior to the switch.~Hypothesis: By withdrawing ARV drug pressure, resistant HIV virus will revert to wild-type. In treatment-experienced HIV patients who experience virologic failure, a STI prior to starting a salvage regimen will result in an improved virologic response and more prolonged vral suppression compared to immediate switching to a new regime.~Interventions:~Immediate Switch to Salvage Therapy: Patients randomized to the control arm will be switched immediately to a salvage regimen using the information from the treatment history and genotype results.~Structured Treatment Interruption: Patients randomized to the STI arm will have their present regimen stopped for 12 weeks and will have a genotype repeated in the 12th week. A salvage regimen will be started at week 12 using the information from the treatment history and baseline genotype results.
The purpose of this study is to assess the virologic impact of switching treatment-experienced HIV-infected patients with virologic failure to a salvage regimen with or without a 12 week STI prior to the switch.~Hypothesis: A STI prior to starting a salvage regimen will result in an improved virologic response.