• Percentage of patients who reach HIV-1-RNA ≤ 50 copies/mL at 48 weeks
  

• plasma Viral Load change from baseline
  
• Clinical symptoms
  
• CD4 counts
  
• Safety
  
• Tolerability
  
• Discontinuations
  

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.