A Phase IIIb Study Comparing Two Boosted Protease Inhibitor-based HAART Regimens in HIV-infected Patients Experiencing Their First Virologic Failure While Receiving an NNRTI-containing HAART Regimen

Inclusion Criteria: * Patients ≥ 18 years of age infected with HIV * Plasma HIV RNA ≥ 1000 copies/mL and CD4 cell count ≥ 50 cells/mm3 * Currently receiving a NNRTI-containing HAART regimen or not currently receiving a NNRTI-containing HAART regimen and have not been treated with an alternative regimen since the documented virologic failure (with genotype performed within 2 weeks of the discontinuation of the failing regimen and the genotype report is available) * The failing NNRTI-containing regimen must be the patient's first virologic failure on treatment and contain a NNRTI and at least 2 NRTIs. The regimen must have been administered for at least 24 weeks and the patient must have documented virologic response to the regimen (HIV RNA \< 400 c/mL) Exclusion Criteria: * Pregnancy or breastfeeding * Reported virologic failure to two or more antiretroviral regimens * Active AIDS-defined opportunistic infection or disease * Proven or suspected acute hepatitis within 30 days prior to study entry