Adult ; Aged ; Antiretroviral Therapy, Highly Active* ; Biological Assay/methods ; Biological Assay/utilization ; Drug Resistance, Viral/genetics* ; Female ; HIV Infections/drug therapy* ; HIV Infections/genetics ; HIV-1/genetics* ; Humans ; Male ; Middle Aged ; Mutation* ; Treatment Outcome ; Viral Load ; Young Adult
Keywords
HIV-1 ; Treatment Failure ; Drug Resistance ; Genotype
Abstract
Resistance assays are useful in guiding decisions for patients experiencing virologic failure (VF) during highly-active antiretroviral therapy (HAART). We investigated antiretroviral resistance mutations in 41 Korean human immunodeficiency virus type 1 (HIV-1) infected patients with VF and observed immunologic/virologic response 6 months after HAART regimen change. Mean HAART duration prior to resistance assay was 45.3+/-27.5 months and commonly prescribed HAART regimens were zidovudine/lamivudine/nelfinavir (22.0%) and zidovudine/lamivudine/efavirenz (19.5%). Forty patients (97.6%) revealed intermediate to high-level resistance to equal or more than 2 antiretroviral drugs among prescribed HAART regimen. M184V/I mutation was observed in 36 patients (87.7%) followed by T215Y/F (41.5%) and M46I/L (34%). Six months after resistance assay and HAART regimen change, median CD4+ T cell count increased from 168 cells/microL (interquartile range [IQR], 62-253) to 276 cells/microL (IQR, 153-381) and log viral load decreased from 4.65 copies/mL (IQR, 4.18-5.00) to 1.91 copies/mL (IQR, 1.10-3.60) (P<0.001 for both values). the number of patients who accomplished viral load <400 copies/mL was 26 (63.4%) at 6 months follow-up. in conclusion, many Korean HIV-1 infected patients with VF are harboring strains with multiple resistance mutations and immunologic/virologic parameters are improved significantly after genotypic resistance assay and HAART regimen change.