Genotypic resistance tests for the management of patients at simplification of highly active antiretroviral therapy.

Witness for the prosecution: There is a growing interest in exploring simpler protease inhibitor (PI)-sparing regimens that could improve patients' quality of life and adherence, provide relief from adverse events and, at the same time, preserve virological and immunological success. Simplified maintenance studies have used switch regimens with equivalent antiretroviral efficacy to PI-containing highly active antiretroviral therapy (HAART), replacing the PI with non-nucleoside reverse transcriptase inhibitors (NNRTI) such as efavirenz and nevirapine or with a 3 nucleoside-based maintenance regimen. As simplification strategies apply to patients with undetectable viral load, the conventional methods to measure viral resistance on plasma RNA cannot be applied. The only possibility relies on the determination of mutations within the integrated HIV-DNA in peripheral blood mononuclear cells. A careful anamnestic examination is therefore the only tool the caregiver has to direct his choices. In this respect and in our opinion it would be wise not to simplify treatment with abacavir in those patients who underwent a previous suboptimal therapy with lamivudine or thymidine analogues. Witness for the defence: The antiretroviral therapy that includes PI and 2 nucleoside analogue reverse transcriptase inhibitors (NRTI) was the first HAART in HIV infection: this combination results in a reduction of the risk of progression to AIDS and death, but it shows many problems caused by high tablet volume, dietary restrictions, multiple daily dosing and development of toxicity. Simplifying antiretroviral treatment regimens would increase patients' adherence and minimize toxicity.