Editorial comment: a plethora or options in multidrug-resistant HIV-1 infection.

Although more than 20 years of antiretroviral therapy use has resulted in the selection of multidrug-resistant (MDR) HIV-1, new drugs in the traditional and newer antiretroviral drug classes provide an increasing range of options for the effective treatment of HIV-1 infection. While the protease inhibitor (PI) darunavir combined with low-dose ritonavir (DRV/r) appears to be the basis for a very active boosted PI regimen, the best way to combine the additional drugs and classes in treatment regimens for PIand NNRTI-experienced patients remains poorly defined. The knowledge base of pharmacological interactions between drugs from the NNRTI class and DVR/r is scant. Further analysis of the DUET studies was recently presented at this year's International AIDS Conference.1,2 The latest results from these pivotal trials continue to demonstrate that an antiretroviral regimen of boosted darunavir given with an optimized background and the second-generation NNRTI etravirine provides new options in the treatment of MDR HIV-1 infection.