Through extensive study of the characteristics of HIV-1 subtypes in Africa, especially HIV-1C, and the genetics of immunity in African populations, HAI researchers are making critical findings that will assist in the development of vaccine designs for Africa.
Vaccine Models for Southern Africa
Several vaccines that use different pieces of HIV-1C are in various stages of development at HAI. There are three vaccine designs that are in consideration for safety trials. The naked DNA plasmid vaccine involves putting HIV genes into plasmids, tiny circles of DNA that bacteria use to swap genetic material among themselves. The vaccinia vector design involves using a harmless pox virus vector that is a modified version of a vaccine used for smallpox vaccination. The modified bacterial toxoid vaccine uses a piece of bacterial toxin that is particularly effective at inserting small proteins into human cells.
Maiteko a Tshireletso HIV Vaccine Initiative
Along with the laboratory investigations dedicated to developing a safe and effective HIV vaccine for southern Africa, the Botswana–HAI Partnership is currently collaborating with local, regional and international institutions and organizations to develop the necessary infrastructure and community awareness to conduct vaccine trials in Botswana. This effort, called "Maiteko a Tshireletso" means "protection effort" in Setswana. A community advisory board has been established to advise the researchers, as well as to educate the community and individuals who are considering volunteering for vaccine trials.
This initiative involves various collaborations. In-country partnerships exist with the Government of Botswana through the Ministry of Health, National AIDS Council, National AIDS Coordinating Agency, the AIDS/STD Unit, and the Vaccine Committee of the Ministry of Health, as well as the Maiteko a Tshireletso Community Advisory Board. The Botswana–HAI Partnership has international partnerships with the HIV Vaccine Trials Network, the National Institutes of Health, and the African AIDS Vaccine Program.
No HIV vaccine design will be evaluated in large-scale efficacy trials until it had been fully approved for safety, and such designs will be concurrently tried for safety in southern Africa and in the United States.
Maiteko a Tshireletso HIV Vaccine Research Studies
Vaccine Preparedness Study
This vaccine initiative will include a number of vaccine studies, beginning with a vaccine preparedness study (VPS). The VPS is designed to evaluate the site’s ability to recruit and retain individuals at risk for HIV infection, provide responsible and comprehensive HIV counseling and testing for study volunteers, evaluate changes in HIV risk behaviors over time, and assess HIV incidence over time. Results from the VPS will guide investigators in the appropriate design of future vaccine trials and other preventive interventions, and will provide researchers and public health officials with valuable information about the demographic characteristics and HIV risk behaviors of the sample population, in addition to important data on the incidence of HIV and the prevalence of other sexually transmitted infections in Botswana. Such information can inform efforts to improve health care and health education in Botswana and to allocate resources where most needed.
Substudies of the VPS will include an assessment of the impact of alcohol use on HIV risk behaviors. There are also plans to develop and test a prototype informed consent process for vaccine efficacy trials. For more information, visit http://www.bhp.org.bw.
Phase I Vaccine Trial
Another forthcoming study of this initiative will be a phase I trial of an HIV vaccine. This trial will be conducted among a small group of volunteers as a first step in evaluating a product that is being considered for larger-scale efficacy trials in the future.
China Initiative
The vaccine efforts of HAI’s China Initiative involve ongoing research from laboratories in China and the United States. In 2000, Principle Research Scientist Yichen Lu of HAI and Ruan Li, Director of the Institute of Virology, Chinese Academy of Preventive Medicine, established joint laboratories working on AIDS vaccine research and development for China and Africa. HAI similarly partners with Nankai University Vaccine Laboratory through researcher exchange and joint laboratory efforts. The China Initiative is currently considering two subtype-C vaccine candidates for further development.
For information on other China Initiative efforts, click here.
HIV Vaccine Trials Network (HTVN)
The Botswana–HAI Partnership in Gaborone is an official site of the HIV Vaccine Trials Network. This provides the Partnership access to additional experimental HIV vaccines that are not developed by HAI researchers. The HIV Vaccine Trials Network, which is funded by the United States National Institutes of Health, conducts all phases of clinical trials, from evaluating candidate vaccines for safety and the ability to stimulate immune responses, to testing vaccine efficacy. For more information about the HVTN, visit http://www.hvtn.org. The Botswana–HAI Partnership plans to begin safety evaluations of a candidate HIV vaccine by late 2002/early 2003 as part of the HVTN.
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