Identification of HIV-1 Genotypic Resistance in Patients on First-line Antiretroviral Therapy Using Polymerase Chain Reaction and Sequencing

Abstract

Abstract Objective The aim of the study was to evaluate the characteristics of HIV drug-genotypic resistance among patients taking first-line ARV regimens using polymerase chain reaction and sequencing, and guide to design optimal ARV regimens for these patients. Methods HIV reverse transcriptase-encoded gene was amplified with RT-PCR and amplified PCR products were aligned and comparatively analyzed with HIV resistance database to find drug-resistance mutations. Results Twenty-eight PCR products were amplified and sequenced successfully in 30 serum samples of recruited HIV-infected patients with virologic failure. The resistance rate was 96%, mutations in NRT region were found in 26 patients (93%), while mutations in NNRT region were found in 27 patients (96%). M184V was the most common mutation (86%), K65R was selected in 14% of recruited individuals and TAMs occurred in 50% of patients, which resulted in resistance to NRTIs. Y181C and V179D were the most common mutations in NNRTIs and prevalence was 43% (12/28) and 36% (10/28), respectively, which resulted in cross-resistance to NNRTIs due to low-genetic barrier. Conclusions Virologic failure may occur in long-term administration of first-line ARV regimens, and drugresistance mutations can be found in these patients, which resulted in resistance to first-line ARV regimens. We emphasized that HIV viral load assay and resistance assay were important tools to guide healthcare workers to design an optimal second-line ARV regimens for HAART-experienced individuals with virologic failure.