[show abstract][hide abstract] ABSTRACT: We compared biological outcomes in antiretroviral-naive patients with viral load (VL) > 5,000 copies/ml starting combivir-based, three-drug highly active antiretroviral therapy regimens in 2001-2002 according to the third component, namely abacavir (ABC), nelfinavir (NFV), indinavir/ritonavir (IDV/r), lopinavir/ritonavir (LPV/r), nevirapine (NVP) or efavirenz (EFV).
We evaluated virological response (HIV RNA < 500 copies/ml) and immunological response (increase of > or = 50 CD4+ T-cells/microl) separately in patients with baseline VL < 100,000 copies/ml (n = 992) and a100,000 copies/ml (n = 1,048). Hazard ratios (HR) were calculated with Cox models stratified for quintiles of propensity scores, estimated by multinomial regression from baseline characteristics.
Median follow up was 19 months. EFV had better virological efficacy than NFV and IDV/r among patients with baseline VL < 100,000 copies/ml, with respective HRs of 0.71 and 0.72, compared with 0.81 for NVP, 0.89 for ABC and 0.99 for LPV/r. The immunological efficacy of EFV was lower than that of LPV/r (1.37) and similar to that of NFV (0.96), IDV/r (0.81), NVP (1.08) and ABC (1.04). Among patients with baseline VL > or = 100,000 copies/ml, the virological efficacy of EFV was similar to that of NVP (0.90) and LPV/r (0.97) and better than that of NFV (0.62), ABC (0.75) and IDV/r (0.78). The immunological results found in these patients were similar to those observed in patients with baseline VL < 100,000 copies/ml.
For first-line therapy, in this observational setting, EFV, LPV/r and NVP, when added to the combivir backbone, were more likely to drive viral load < 500 copies/ml. LPV/r showed the best immunological effectiveness.