CD4 and AIDS: In a multivariable Cox regression model that adjusted for age (≥ 50 vs. < 50), AIDS status, route of transmission, baseline CD4+ T cells (≥ 100/μL vs < 100 μL) and HIV-1 RNA values (≥ 5 log10 vs. < 5 log10 copies/mL), the AHRs for switch, compared to NNRTI-based regimens, were 4,21 (95%CI: 1.70-10.4, p = 0.002) for ritonavir-boosted PIs regimens and 3.88 (95%CI: 1.40-10.7, p = 0.009) for unboosted PIs regimens (Table 3).