To conduct large-scale U.S. trials of vaccines to prevent HIV infection, as well as other HIV prevention strategies, the National Institute of Allergy and Infectious Diseases of the National Institutes of Health in 1993 established a specialized clinical trials network called the HIV Network for Prevention Trials (HIVNET).  The HIVNET is a multi-center, collaborative research network whose mission is to carry out HIV prevention efficacy trials.  In most cases, the primary aim of these studies was to measure the effect of prevention interventions on reducing the number of new HIV infections. As HIVNET Domestic Master Contractor, Abt Global, coordinated, administered, and monitored a network of 11 U.S. field sites.  Enrollment of 255 volunteers at eight of these sites was completed in January 1998 for a Phase II trial of the safety and immune responses elicited by two candidate vaccines given together:  ALVAC vCP 205, manufactured by Pasteur-Merieux/Connaught Laboratories, and HIV-1 SF-2 rgp120, manufactured by Chiron vaccines.  Pending a decision on proceeding to a large-scale trial of these or similar products — involving thousands of volunteers in the U.S. (and possibly a parallel study in Brazil and the Caribbean basin) — Abt Global participated actively in protocol development, implementation, and analysis of other important prevention research projects, including:

• Initiation in February 1999 of the largest behavioral intevention trial for men who have sex with men ever conducted, in which 4,350 men were randomized to receive either a ten-session cognitive-behavioral intervention to reduce HIV risk behavior or standard semiannual HIV counseling and testing.  The major outcome was the extent to which a measure reduction in new HIV infections could be effected through the enhanced intervention.
• The first large-scale observational study to demonstrate high rates of incident HIV infections among U.S. women at risk through heterosexual exposure.
• Implementation of Phase I (safety) trials of microbicides — chemical barriers designed for vaginal, and possibly rectal, administration prior to sexual contact that would destroy HIV and other STDs before infection could occur.
• Development and successful randomized evaluation of a model procedure for assuring adequate informed consent for vaccine trials among populations at high risk with low literacy and minimal educational backgrounds.
• An evaluation establishing the superiority of audio-assisted computer interviewing over face-to-face interviews for measuring sensitive topics such as sexual and drug injection-related risk behaviors.
• A demonstration of the feasibility of having high risk study participants collect blood and saliva specimens at home for bimonthly HIV testing.