Evolution of HIV-1 drug resistance in patients failing combination antiretroviral therapy

Abstract

This study aimed to evolution of genotypic drug resistance prevalence in treatment-failing patients in Shenzhen. Peripheral venous blood samples were collected from 41 AIDS patients whom failing combination antiretroviral therapy, and were amplified by nested PCR; then the amplified fragments were sequenced and analyzed. Partial pol sequences of 38 samples were successfully amplified, and 3 samples have not found any mutations in their pol sequences. K103N, G190A, Y181C, K101P, M184V, D67N, K70R, T215Y and K219 were most common mutations. According to the genotypic analysis, 100% of the patients (35/35) showed high and intermediate level resistance to nevirapine (NVP) and efavirenz (EFV); above 50% of the patients showed high and intermediate level resistance to zidovudine (AZT), lamivudine (3TC), stavudine (D4T) and didanosine (DDI); only a few patients showed intermediate and low level drug resistance to protease inhibitors (PIs). Patients whom take D4T + DDI + NVP regimens were most common to appear drug mutation. The high prevalence of drug resistance to NNRTIs and NRTIs among patients failing combination antiretroviral therapy in Shenzhen. That is the main reason for treatment failure in AIDS patients. Now most of mutations were detected against NNRTIs and NRTIs, only a few against PIs. Our finding suggested that a second-line antiretroviral therapy regimens is needed among the patients failing therapy and the boosted-PIs maybe are good choice.