Differential CD4 T-cell response in HIV-1-infected patients using protease inhibitor-based or nevirapine-based highly active antiretroviral therapy

Objectives To study the dynamics of CD4 T-lymphocyte counts (CD4 counts) after the initiation of either protease inhibitor (PI)-based or nevirapine (NVP)-based first-line highly active antiretroviral therapy (HAART). Design and methods A retrospective cohort study of 1029 HIV-infected antiretroviral therapy-naive patients initiating either PI-based or NVP-based HAART was carried out. Patients were censored as soon as they experienced virological failure, or changed their original antiretroviral regimen for any reason. Results In total, 920 and 109 patients initiated PI- and NVP-based HAART, respectively. The patients in the PI group more often had AIDS (15 vs. 6% in the NVP group), had a lower median baseline CD4 count (234 vs. 250 cells/muL in the NVP group) and had higher median baseline plasma HIV-1 RNA levels (pVL) (5.0 vs. 4.7 log(10) HIV-1 RNA copies/mL in the NVP group). After 96 weeks of follow-up, the mean increase from baseline in CD4 count, adjusted for baseline CD4 count, age, gender and baseline pVL, was 3 10 cells/muL in the PI group and 212 cells/muL in the NVP group (P = 0.003). This difference was mainly attributable to the patients in the NVP group initiating HAART with a baseline CD4 count below 200 cells/muL. There were no differences between the PI and NVP groups with respect to the change in the number of CD4 cells as a proportion of the total number of lymphocytes. Conclusion Patients successfully treated with NVP-based HAART have a smaller increase in absolute CD4 cells compared with those treated with PI-based HAART