Objective: To compare virological and immunological responsiveness of efavirenz (EFV)-based highly active
anti retroviral therapy (HAART) between patients with baseline CD4 < 100 and CD4 > 100 cells/mm3.
Material and Method: A prospective cohort study in antiretroviral-naive HIV-infected patients was conducted
between February and April 2002. Donated HAART regimen, consisting of stavudine, didanosine, and
EFV was initiated. The primary outcome was time to undetectable HIV RNA, < 50 copies/mL. Patients were
followed up every 12 weeks until 48 weeks (the end of the study).
Results: Forty-six patients were included, 21 patients for CD4 < 100 cells/mm3 and 25 patients for CD4 >100
cells/mm3. Median CD4 cell counts of these corresponding groups were 26.5 and 177 cells/mm3. Patients’
characteristics were similar between the two groups except CD4. The probability of undetectable HIV RNA at
12, 24, 36, and 48 weeks were 57.1% (95%CI, 37.7-78.1%), 76.2% (95%CI, 56.9-91.3%), 80.9% (95%CI,
62.3-94.0%), and 90.5% (95%CI, 68.9-99.1%) for the former group; and 64.0% (95%CI, 45.8-81.8%), 92.0%
(95%CI, 77.5-98.6%), 96.0% (95%CI, 83.0-99.7%), and 96.0% (95%CI, 83.0-99.7%) for the latter group.
Median time to undetectable HIV RNA was 12 weeks for both groups. Median CD4 change at 48 weeks was
171 and 132 cells/mm3, respectively (p = 0.232). The adverse events were similar between the two groups.
Conclusion: Initiation of EFV-based HAART regimen in HIV-infected patients at CD4 < 100 and > 100 cells/
mm3 gains similar immunological and virological response.

Keywords: AIDS, CD4, Efavirenz, Highly active antiretroviral therapy, HIV