Current guidelines for initial therapy in HIV infection recommend 2 NRTIs plus either a ritonavir boosted protease inhibitor or a non-nucleoside reverse transcriptase inhibitor (NNRTI). Recent data suggests that the rate of response to PI based therapy may be slightly compromised if the baseline CD4 count is ≤ 200/mm3 and the plasma HIV-1-RNA ≥ 100,000 copies/mL. This may not be equally apparent if ritonavir boosted protease inhibitors are used. The effect of baseline CD4 count and HIV-1-RNA levels on the antiviral efficacy of NNRTI based regimens has been less well characterized. A significant number of patients currently initiate therapy at late stages of progression, typically with baseline CD4 count is ≤ 200/mm3. In Mexico approximately 60% of patients who initiate therapy are within this range of CD4 cell counts. Currently, the two combinations recommended as preferred are with two NRTIs and either Efavirenz or Lopinavir/ritonavir, while other combinations of PIs and ritonavir are considered alternative.~Comparison: The efficacy of ritonavir boosted protease inhibitor based therapy versus NNRTI based therapy in patients who are antiretroviral therapy naïve and initiate therapy with a CD4 count ≤ 200/mm3.
Ritonavir boosted protease inhibitor based therapy will have equivalent antiviral efficacy over 48 weeks compared to NNRTI based therapy in patients who are antiretroviral therapy naïve and initiate therapy with CD4 counts ≤ 200/mm3.