title: HIV sexual risk behavior over 36 months of follow-up in the world's first HIV vaccine efficacy trial.
abstract: Increased risk behavior among participants in HIV vaccine efficacy trials has been a concern. This study evaluated HIV sexual risk behavior among 5095 HIV-negative men who have sex with men (MSM) and 308 women enrolled in a randomized, double-blind, placebo-controlled efficacy trial of a bivalent rgp120 vaccine at 61 sites, primarily in North America. Sexual risk behavior data were collected at baseline and semiannually for 36 months. Overall, sexual risk behavior did not exceed baseline levels during the trial. Among MSM, younger age (< or =30 years), perceived assignment to vaccine, and nonblack race were associated with an increased probability of unprotected anal sex. Among women, unprotected vaginal sex initially decreased but was statistically equivalent to baseline by 24 months, whereas unprotected vaginal sex with HIV-infected partners decreased from baseline, where it remained throughout the trial. HIV sexual risk behavior did not increase among trial participants; however, it was substantial throughout the trial. Consistently high levels of risk behavior and the association of these behaviors to perceived assignment and demographic variables underscore the need for vigilant HIV risk reduction counseling, informed consent, and educational processes in the context of HIV vaccine efficacy trials.
authors.affiliation: Centers for Disease Control and Prevention, Atlanta, GA 30333, USA. bub1@cdc.gov
authors.forename: Bradford N
authors.initials: BN
authors.lastname: Bartholow
authors.forename: Susan
authors.initials: S
authors.lastname: Buchbinder
authors.forename: Connie
authors.initials: C
authors.lastname: Celum
authors.forename: Vamshidar
authors.initials: V
authors.lastname: Goli
authors.forename: Beryl
authors.initials: B
authors.lastname: Koblin
authors.forename: Michael
authors.initials: M
authors.lastname: Para
authors.forename: Michael
authors.initials: M
authors.lastname: Marmor
authors.forename: Richard M
authors.initials: RM
authors.lastname: Novak
authors.forename: Kenneth
authors.initials: K
authors.lastname: Mayer
authors.forename: Catherine
authors.initials: C
authors.lastname: Creticos
authors.forename: Patti
authors.initials: P
authors.lastname: Orozco-Cronin
authors.forename: Vladimir
authors.initials: V
authors.lastname: Popovic
authors.forename: Timothy D
authors.initials: TD
authors.lastname: Mastro
mesh_terms: D016915:AIDS Vaccines; D000328:Adult; D002170:Canada; D004522:Educational Status; D005260:Female; D005500:Follow-Up Studies; D015658:HIV Infections / Q000276:immunology* / Q000635:transmission*; D018451:Homosexuality, Male; D006801:Humans; D008297:Male; D009042:Motivation; D009426:Netherlands; D010919:Placebos; D044469:Racial Groups; D012309:Risk-Taking; D012725:Sexual Behavior; D011795:Surveys and Questionnaires; D014481:United States
chemical_list: D016915:AIDS Vaccines; D010919:Placebos