An estimated 5 million new HIV infections occurred worldwide in the year 2001, or 15,000 new infections each day.1 Deaths from HIV/AIDS-related illnesses in the same year numbered approximately 3 million people, most being in developing countries.1 With these staggering statistics in mind, researchers are working fervently in their search for an HIV vaccine. A vaccine is the best tool for halting the spread of HIV infections throughout the world, which is why the National Institute of Allergy and Infectious Diseases (NIAID) regards the discovery and development of a preventive HIV vaccine a top priority in its research agenda. In an effort to advance this initiative, NIAID created the HIV Vaccine Trials Network (HVTN).
The HVTN is a network of clinical sites in the United States and abroad that is dedicated to the development of an HIV vaccine through testing and evaluating candidate vaccines in clinical trials. The network includes 18 sites in the United States and 11 international sites, including sites in Africa, Asia, South America and the Caribbean. The HVTN's global capacity will allow for rapid expansion as more vaccine candidates enter the pipeline for testing and development, and for carrying out larger scale studies of suitable vaccines.
The HVTN is built on the previous work and accomplishments of NIAID's AIDS Vaccine Evaluation Group (AVEG) and the HIV Network for Prevention Trials (HIVNET). The AVEG conducted early-stage testing of vaccine candidates, while HIVNET conducted U.S. and international clinical trials of HIV prevention strategies, including experimental vaccines. Many AVEG and HIVNET investigators have since joined the HVTN. The new network will conduct all phases of clinical research, following a scientific agenda established by a scientific steering committee composed of HVTN investigators, community representatives, NIAID's staff and some ad hoc members. The scientific steering committee will set research priorities and monitor the results of the ongoing activities. The HVTN infrastructure is composed of an operations center, which provides administrative, technical and operational support to the network; a Statistical and Data Management Center; and a Central Laboratory.
Phase I Trials - Phase I studies of HIV vaccine candidates will be carried out at domestic and international sites in people who have a low risk of becoming infected with HIV. These studies will test vaccines for safety and ability to stimulate an immune response, and will provide data that will assist in determining which vaccines should be advanced into larger Phase II trials.
Phase II Trials - Phase II studies will be conducted at a larger number of U.S. and international sites, and will expand upon testing in Phase I trials to include people who engage in behaviors that put them at high risk for acquiring HIV. These studies may include injection drug users and people who have unprotected sex and/or multiple sex partners.
Phase III Trials - Phase III efficacy studies will be conducted on a large scale at all HVTN sites in people who engage in high-risk behaviors. It is expected that each of these trials will require enrollment of several thousand volunteers.
The participation of international sites and the involvement of ethnically diverse populations in the HVTN are critical components of NIAID's HIV vaccine effort. They allow for studies that examine differences in genetic background, nutritional status, effects of other infections, and access to health care, all of which are factors that are crucial to developing an effective vaccine for use around the world. The international capacity of the network also facilitates studies of various HIV subtypes that may affect only a minority of the population, but nonetheless may be important to the development of a vaccine that will protect people from different circulating strains of the virus.
In addition to conducting clinical studies, the HVTN will initiate community outreach programs to educate people about HIV and vaccine research, and to encourage participation in clinical trials. Through this initiative, the HVTN hopes to enroll a diversified population in its clinical trials, with an emphasis on recruiting minorities and women.
The network also collaborates with and supports vaccine research conducted by private industry, academia and other government agencies. NIAID also supports the National HIV Vaccine Communications Steering Group, which is composed of representatives from community-based organizations, HIV vaccine advocates and communications consultants. The steering group complements HVTN outreach and communications activities on a national scale, focusing specifically on stimulating communication about the issues surrounding HIV vaccine research and promoting a positive environment for conducting clinical trials.
The domestic and international clinical sites and their principal investigators are listed below.United States
NIAID is a component of the National Institutes of Health (NIH). NIAID supports basic and applied research to prevent, diagnose, and treat infectious and immune-mediated illnesses, including HIV/AIDS and other sexually transmitted diseases, illness from potential agents of bioterrorism, tuberculosis, malaria, autoimmune disorders, asthma and allergies.