Antiretroviral Therapy: Regimens, Predictors of Response, and Clinical Outcomes
Thursday, 1:30 - 3:30 pm
Background: Assesment of of multiple immunovirologic parameters may be useful in determining optimal combinations of antiretrovirals.
Methods: We enrolled 76 HIV-infected naive patients (66
male, 9 female; 28 injecting drug users [IDU]; 15 men who have sex with men [MSM],
33 heterosexual) in a study to compare different antiviriral regimens (zidovudine
[AZT]/didanosine [ddI]/abacavir [ABC]; AZT/lamivudine [3TC]/ABC; AZT/ddI/efavirenz
[EFV]; AZT/3TC/EFV; AZT/ddI/indinavir+ritonavir [IDVr], and AZT/3TC/IDVr).
Median CD4 count and viremia at baseline were 217/mm3 and 238,301
copies/mL, respectively. Quantitative (CD4 counts) and qualitative (
Results: All regimens resulted in increases in CD4
counts and suppression of HIV plasma viremia. Median CD4 count at 6 months was
significantly better in ABC-treated patients than in all other groups, and was
also significantly more solid in 3- vs 4-drugs-treated patients (median CD4
count: 3 drugs = 373 CD4/mm3;
4 drugs = 246 CD4/mm3; p =
0.01). The best suppression of HIV viremia (all patients with > 50 copies/mL)
was observed in AZT/3TC/ABC patients.
Conclusions: These results suggest that ABC-containing regimens are associated with the highest CD4 counts and the strongest suppression of HIV plasma viremia, whereas boosted PI-containing regimens have a more robust effect on functional immune parameters after 6 months from starting thepaphy in drug-naive patients.
Keywords: antiretroviral therapy; immunology; cliniclal benefit