AEGiS-14IAC: Prevalence of HIV-1 genotypic mutations in the protease and reverse transcriptase genes from infected individuals in Taiwan: Treatment challenges.

14th International AIDS Conference

Barcelona, Spain - July 7-12, 2002

Prevalence of HIV-1 genotypic mutations in the protease and reverse transcriptase genes from infected individuals in Taiwan: Treatment challenges.

Int Conf AIDS 2002 Jul 7-12; 14:(abstract no. B10203)

Elbeik T, Lan YC, Dileanis J, Marlowe N, Ng V, Chen YM
University of California, San Francisco and San Francisco General Hospital, San Francisco, United States

BACKGROUND: Increasing prevalence of HIV-1 genotypic resistant strains in newly infected presents a challenge to treatment strategies. We investigate the prevalence of HIV-1 genotypic mutations in retrospective samples collected between 1996-2000 from cohorts of recently infected subjects in Taiwan.

METHODS: Cohort studied: Heterosexual male (Ct1) n=34, Homosexual male (Ct2) n=66, Bisexual male (Ct3) n=34, Female (Ct4) n=8, Intravenous Drug Users (Ct5) n=8. Plasma from recently infected subjects (n=150), 90% without treatment, 10% with < 3 months treatment, was analyzed using Applied Biosystems' ViroSeq é « HIV-1 Genotyping System, Version 2 for resistance mutations. Subtype and phylogenetic tree determined from reverse transcriptase (RT) and protease (PRO) sequences.

RESULTS: Primary mutations: 6/150 (4%); Ct2 in 2/66 (3%) M184V (RT) each, and Ct5 in 4/8 (50%), two with M184V (RT), one with T69D (RT) and one with L90M (PRO), V75T (RT), Y181C (RT). Secondary mutations: 131/150 (87%): PRO: 119/150 (79%), RT 2/150 (1%), PRO and RT: 9/150 (6%). No resistance mutations: 19/150 (13%); Ct1: 4/34 (12%), Ct2: 9/66 (14%), Ct3: 5/34 (15%), Ct4: 1/8 (13%) and Ct5: 0/8 (0%). Subtypes: Ct1: 30B, 4A/E; Ct2: All B; Ct3: All B, Ct4: 2B, 1C, 5A/E; Ct5: 7B, 1A/E

CONCLUSION: Primary mutation in 4% of all samples confined to 50% Ct5 with resistance to reverse transcriptase inhibitors (rti) and protease inhibitors (pi) and 3% of Ct2 with resistance to rti. While secondary mutations were frequently detected (87%), most individuals had only 1 to 2 which is insufficient to confer resistance. However, 2 subjects in Ct2 and 1 subject in Ct3 each had 3 secondary mutations sufficient for resistance to pi. Cluster analysis shows viral spread within and between cohorts, and subtype most heterogeneous for Ct4. While overall genotypic resistance is low it is unclear if the preponderance of secondary mutations may impact on treatment; longitudinal studies are planned.

Keywords: AEGIS, RNA-Directed DNA Polymerase, HIV-1, Prevalence, Reverse Transcriptase Inhibitors, Mutation, Endopeptidases, Antiretroviral Therapy, Highly Active, Substance Abuse, Intravenous, Protease Inhibitors, Genotype, Drug Therapy, Combination, Longitudinal Studies, Retrospective Studies, Taiwan, Female, Male, therapy, epidemiology, genetics, drug therapy

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B10203