Current concepts in antiretroviral therapy failure.

Currently, the goal for the first and second, possibly the third, antiretroviral regimen is the suppression of HIV replication to plasma levels below assay detection (ie, <50 HIV-1 RNA copies/mL). In patients with advanced treatment failure and resistance to numerous drugs, the goal of therapy has been to reduce viral load as much as possible and to maintain immunologic and clinical integrity. With the recent availability of new drugs and new classes of drugs, complete suppression of viral replication may be possible even in late salvage. When designing a regimen for a patient for whom antiretroviral therapy has failed, the regimen should contain at least 3 active drugs, and regimens are best selected with assistance from genotypic and phenotypic drug resistance testing. The selection should also be guided by knowledge of potential pharmacokinetic interactions among drugs. This article summarizes a presentation on antiretroviral failure by Carlos del Rio, MD, at the 8th Annual clinical meeting for Ryan White CARE Act clinicians in New Orleans in June 2005, sponsored by the International AIDS Society-USA and includes more recent data presented at the 13th Conference on Retroviruses and Opportunistic Infections (CROI) in 2006.