In order to adjust for possible clinical differences (i.e. different proportion of patients with AIDS between groups) and for the non-randomized attribution of treatment, a multivariable logistic regression model that used immunovirological success as dependent outcome and age (≥ 50 vs. < 50), type of regimen (PI-based vs. NNRTI-based), route of transmission, AIDS status, baseline CD4+ T cells (≥ 100/μL vs. < 100 μL) and HIV-1 RNA levels (≥ 5 log10 vs. < 5 log10 copies/mL) as covariates was constructed. This evidence concerns the gene CD4 and AIDS.