title: Minority HIV-1 resistant variants in recent infection and in patients who failed first-line antiretroviral therapy with no detectable resistance-associated mutations in Thailand.
abstract: Through the Thai National AIDS Program, approximately 200,000 patients infected with HIV are on antiretroviral (ARV) therapy. Although studies have shown low prevalence of primary HIV-1 resistance transmission in Thailand and in Southeast Asia where subtype CRF01_AE is predominant, minority HIV-1 drug resistance has not been studied. Two groups of patients, whose conventional genotyping results showed no drug resistance-associated mutations, were investigated: 104 homosexual men recently infected with HIV-1, naïve to ARV treatment and 22 first-line non-nucleoside reverse transcriptase inhibitor (NNRTI)-based failure patients. Pyrosequencing (PSQ) assay was developed to detect and quantify minority Y181C and M184V variants from the patients' plasma samples. The sensitivity of PSQ to detect minority Y181C and M184V variants was approximately 1%. 1/104 (0.5%) and 3/101 (3%) samples were found harboring Y181C and M184V in the group of homosexual men recently infected with HIV-1. In patients with first-line treatment failure, one had a minority M184V mutation (4.5%). The prevalence of Y181C and M184V minority variants in homosexual men recently infected and naïve to treatment was low in Thailand. Systematic monitoring of primary resistance transmission in Thailand and this region is essential to guide whether genotypic resistance test is required prior to commencing the first-line highly active antiretroviral therapy (HAART).
authors.affiliation: Vaccine and Cellular Immunology Laboratory, Vaccine Research Center, Chulalongkorn University, Bangkok, Thailand.
authors.forename: Hai
authors.initials: H
authors.lastname: Le Nguyen
authors.forename: Patrawadee
authors.initials: P
authors.lastname: Pitakpolrat
authors.forename: Sunee
authors.initials: S
authors.lastname: Sirivichayakul
authors.forename: Constance
authors.initials: C
authors.lastname: Delaugerre
authors.forename: Kiat
authors.initials: K
authors.lastname: Ruxrungtham
mesh_terms: D000328:Adult; D019380:Anti-HIV Agents / Q000494:pharmacology / Q000627:therapeutic use; D023241:Antiretroviral Therapy, Highly Active; D024882:Drug Resistance, Viral / Q000235:genetics*; D014644:Genetic Variation; D005838:Genotype; D015658:HIV Infections / Q000188:drug therapy* / Q000453:epidemiology*; D015497:HIV-1 / Q000145:classification / Q000187:drug effects* / Q000235:genetics; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D009154:Mutation; D015995:Prevalence; D018894:Reverse Transcriptase Inhibitors / Q000494:pharmacology / Q000627:therapeutic use; D017422:Sequence Analysis, DNA / Q000379:methods; D013785:Thailand / Q000453:epidemiology; D017211:Treatment Failure; D055815:Young Adult
chemical_list: D019380:Anti-HIV Agents; D018894:Reverse Transcriptase Inhibitors