To conduct successful trials, the ability of study sites to recruit, enroll, retain, and inform cohorts at risk for HIV infection is critical. Building a site's capacity for these functions is an essential component of overall preparedness for HIV vaccine trials. The design of Phase III HIV vaccine trials to be conducted in the HVTN will depend on the interplay of 4 parameters: the number of participants enrolled, the HIV incidence rate among enrollees, the duration of follow-up, and the number of participants retained in follow-up. Dramatically different study designs may be required depending on these parameters, and information must be obtained to characterize these parameters at HVTN sites. Based on previous work, many of the HVTN research sites have established effective standard operating procedures to recruit and retain high-risk populations in research studies and have characterized HIV incidence rates in these populations. Work is now required to establish a similar research infrastructure and knowledge base at potential expansion sites not previously represented in HIV vaccine research networks and to assess the potential for recruitment of new cohorts by existing HVTN sites. This HIV Vaccine Preparedness Study (VPS) serves that purpose.
Each study site targets 1 or more major risk groups (heterosexual men or women at high sexual risk, men who have sex with men (MSM), or injection drug users (IDU)) for enrollment. Within each group, 200 to 500 HIV-negative participants are enrolled. Potential study participants undergo a screening interview to identify persons at high-risk for HIV infection. Those who meet the study eligibility criteria (except for HIV testing), as well as any additional site-specific criteria, complete a Behavioral Risk Assessment, receive HIV pre-test and risk reduction counseling, and are tested for HIV antibody and syphilis. Women must provide a urine sample for pregnancy testing. Participants who test HIV-negative and meet all other eligibility criteria are enrolled in the study and maintained in follow-up over the next 12 months. Specifically, participants complete "locator contacts" at Months 3 and 9 and follow-up visits at Months 6 and 12. The Months 3 and 9 locator contacts serve the purpose of enhancing retention in the study by providing a mechanism to confirm or update participants' locator information; confirm or reschedule their next follow-up visit; and reinforce instructions to contact the study site to update locator information and/or, if needed, request HIV counseling and/or testing between scheduled visits. The follow-up visits at Months 6 and 12 will include assessments, counseling, and testing similar to those done at the screening visit.