650
ART Resistance, HIV-1 Tropism, and HIV-1 Subtype among Men Who Have Sex with Men Recently Infected with HIV-1 in the US: The EXPLORE Study
Susan H. Eshleman*1, M Husnik2, S Hudelson1, D Donnell2, Y Huang3, W Huang4, J Jackson1, T Coates5, M Chesney6, and B Koblin7
1Johns Hopkins Univ Sch of Med, Baltimore, MD, US; 2Fred Hutchinson Cancer Res Ctr, Seattle, WA, US; 3Emory Univ, Atlanta, GA, US; 4Monogram Biosci, South San Francisco, CA, US; 5Univ of California, Los Angeles, US; 6NIH, Bethesda, MD, US; and 7New York Blood Ctr, New York, NY, US
Background: ART may be complicated in individuals
infected with ART-resistant or non-subtype B HIV-1 strains. HIV-1 tropism may
also affect disease progression. We analyzed ART resistance, HIV-1 subtype, and
HIV-1 tropism among 195 men who have sex with men (MSM) from 6 major cities in
the United States,
using samples collected within 6 months of HIV-1 seroconversion
(1999 to 2003).
Methods: HIV-1 genotyping was performed using the ViroSeq HIV-1 Genotyping System. HIV tropism was analyzed
using a commercial co-receptor tropism assay, Trofile™
(Monogram Biosciences). HIV-1 subtyping was performed
by phylogenetic analysis of pol region sequences.
Results: Of the 195 men, 31 (15.9%) had evidence of ART
resistance, and 7 (3.6%) had multi-class resistance, including 3 (1.5%) with
resistance to all 3 ART classes. We found no statistically significant
association of ART resistance with demographic factors, sexual practices,
self-reported sexually transmitted infections, use of recreational drugs, or
use of ART post-exposure prophylaxis. All samples were HIV-1 subtype B; 4 men
had CXCR4-using HIV-1 strains, 1 of whom also had ART resistance.
Conclusions: ART resistance is relatively common among
recently infected MSM in the United
States. CXCR4-using strains were detected in
a small number of these infections, which were all subtype B HIV-1.
|
