In BMS Study 045, once-daily (QD) atazanavir/ritonavir (ATV/RTV) demonstrated comparable efficacy and safety to twice-daily (BID) lopinavir/ritonavir (LPV/RTV) over 48 weeks in treatment-experienced patients. Results of extended follow-up to 96 weeks are presented in the March 21 issue of AIDS.

BMS Study 045 was an open-label, randomized, multi-national trial in HIV patients who had failed on two or more HAART regimens. The aim of the study was to assess the effectiveness and safety of boosted atazanavir (ATV/RTV) 300/100 mg once daily and lopinavir ritonavir (LPV/RTV) 400/100 mg twice daily, each with tenofovir 300 mg once daily and one NRTI.

The primary efficacy measure was the time-averaged difference (TAD) in reduction in HIV RNA from baseline.

Results:

·         Over 96 weeks, the ATV/RTV regimen demonstrated similar virologic efficacy to the LPV/RTV regimen.

·         Mean reductions from baseline in HIV RNA were -2.29 and -2.08 log10 copies/ml, respectively.

·         The LPV/RTV regimen resulted in significant increases in total cholesterol (+9%) and fasting triglycerides (+30%) in comparison with the ATV/RTV regimen, which demonstrated decreases in these parameters.

·         Grade 2-4 diarrhea occurred less frequently in ATV/RTV patients (3%) in comparison with LPV/RTV patients (13%) (P < 0.01).

·         Grade 3-4 elevations in bilirubin were more common in ATV/RTV patients (53%) than LPV/RTV patients (< 1%) (P < 0.0001), with no resulting discontinuations.

In conclusion, the authors write, “Regimens containing once-daily ATV/RTV demonstrated comparable efficacy and safety, with significant reductions in total cholesterol and fasting triglycerides and improved gastrointestinal-tolerability in comparison with twice-daily regimens containing LPV/RTV over 96 weeks in treatment-experienced patients.”

03/07/06

Reference
M Johnson and others.96-week comparison of once-daily atazanavir/ritonavir and twice-daily lopinavir/ritonavir in patients with multiple virologic failures. AIDS 20(5): 711-718, March 21, 2006.