Background: The initial antiretroviral therapy (ART) regimens recommended
by most national treatment guidelines in resource-limited settings consist of two Nucleoside
Reverse-Transcriptase Inhibitors (NRTIs) and one Non-Nucleoside Reverse-
Transcriptase Inhibitor (NNRTI). The NRTIs are Zidovudine (AZT) or Stavudine (d4T)
with Lamivudine (3TC); the NNRTI components are either Nevirapine (NVP) or Efavirenz
(EFV). Existing data regarding the effectiveness of Vonavir compared to other
first-line ART regimens in increasing CD4+ T cell counts are unsatisfactory.
Methods: Immunological outcomes of 134 individuals who were on initial stage of antiretroviral
therapy with Vonavir or a combination of Zidovudine/Lamivudine and Efavirenz
were analyzed. The immunological response was then assessed during 28 weeks.
Results: Both groups demonstrated a significant increase in their CD4+ T cell count
which was greater in Zidovudine/Lamivudine and Efavirenz treated group. We observed
a noticeable increase in CD4+ T cells rates in the first three months of therapy;
however, our results indicated a greater increase of cell counts in individuals with
baseline CD4 lower than 100 cells/mm3 treated with Vonavir in first 12 weeks of
treatment compared to those with higher baseline CD4.
Conclusion: A rapid CD4+ Tcell increase occurred shortly after beginning ART
consisting either Vonavir or combination of Zidovudine, Lamivudine and Efavirenz.
Late increases in CD4+ T cell counts were more pronounced in therapy using Zidovudine/
Lamivudine and Efavirenz.