Partner-specific sexual behavioral differences between phase 3 HIV vaccine efficacy trial participants and controls: Project VISION.
OBJECTIVE
To assess and compare sexual behaviors using partner-specific data between HIV-negative men who have sex with men (MSM) recruited for an HIV vaccine efficacy trial and a control group.


METHODS
HIV-negative MSM from an HIV vaccine trial (n = 525) and controls (n = 732) were recruited by similar strategies and interviewed about behaviors with the 3 most recent partners in the past 6 months, obtained by audio computer-assisted self-interview (A-CASI).


RESULTS
Vaccine trial participants were more likely than controls to report an HIV-positive partner (24.7% and 14.1%, respectively) or an HIV-positive primary partner (16.1% and 6.8%, respectively) and were less likely to report occasional or single-time partners of unknown HIV status (51.6% and 63.2%, respectively; P < 0.05 for each comparison). Vaccine trial participants more often reported receptive unprotected anal intercourse (UAI) during their last sexual encounter with an HIV-positive partner (adjusted odds ratio [OR] = 2.7, 95% confidence interval [CI]: 1.0 to 7.9). Most believed their HIV-positive partners were receiving antiretroviral treatment (ART), however, and after adjustment for perceived ART use, the association between vaccine study participation and receptive UAI with an HIV-positive partner was not significant.


CONCLUSIONS
High-risk sexual behavior was reported by many VAX004 participants and controls. Differences between vaccine trial and control participants in the highest risk per contact behavior, receptive UAI with HIV-positive partners, was partly accounted for by perceived ART use. Partner level data are useful in refining risk assessment, which is important in the evaluation of HIV vaccine and other prevention trials.
Whittington
William L H
WL
Department of Medicine, University of Washington, Seattle, WA 98104, USA.
Morris
Martina
M
Buchbinder
Susan P
SP
McKirnan
David J
DJ
Mayer
Kenneth H
KH
Para
Michael F
MF
Bartholow
Bradford N
BN
Celum
Connie L
CL
D016915:AIDS Vaccines; D023241:Antiretroviral Therapy, Highly Active; D017326:Clinical Trials, Phase III as Topic; D005260:Female; D015658:HIV Infections / Q000188:drug therapy* / Q000517:prevention & control / Q000523:psychology* / Q000635:transmission; D006679:HIV Seropositivity; D006801:Humans; D008297:Male; D012309:Risk-Taking; D012725:Sexual Behavior / Q000706:statistics & numerical data*; D012747:Sexual Partners
D016915:AIDS Vaccines