Guardian Profiles Ugandan HIV Vaccine Studies; Different Vaccine To Be Tested in Botswana
An HIV vaccine that is currently in clinical trials in Uganda is "widely seen as the most promising of a global crop of trial vaccines," the Guardian reports in the latest installment of its occasional series on HIV/AIDS. The trials, which began recently in Entebbe, Uganda, are using the DNA-MVA HIV vaccine (Carroll, Guardian, 5/20). The vaccine will be administered to 50 volunteers who are considered to be at low risk for HIV infection in order to determine whether the vaccine is safe. The vaccine was developed by scientists from the U.K. Medical Research Council's Human Immunology Unit at the University of Oxford and Kenya's University of Nairobi, with funding from the International AIDS Vaccine Initiative. The two-part vaccine is made from "copies of a selection of HIV genes which are incapable of forming the fully functional virus." In both vaccine components, genetic information from the virus is delivered to the body; the first component delivers HIV genetic material via "naked" DNA, while the second, known as MVA, or modified vaccinia Ankara, uses a weakened pox virus to deliver HIV genetic material (Kaiser Daily HIV/AIDS Report, 2/13). Phase II trials of the vaccine are under way in Britain and Kenya.
HIV-Resistant Population Found
Researchers at the Uganda Virus Research Institute have also identified near Lake Victoria a group of "discordant couples," in which one of the partners remains HIV-negative despite having unprotected sex with their HIV-positive partner, the Guardian reports (Guardian, 5/20). Researchers are "most excited" about the minority of resistant partners who possess CD4+ T cells that kill cells infected with HIV "in a narrow, targeted attack," unlike their partners whose immune systems launch "wider, bigger -- and unsuccessful -- attacks." Some of the HIV-resistant individuals showed a lower measured immune response than their HIV-positive partners, but their immune systems responded to the virus more effectively, keeping them HIV-negative, the Guardian reports (Carroll, Guardian, 5/20). Research on this group is expected to be published later this year after it is submitted to a journal in June, the Guardian reports. Anthony Kebba, a co-author of the study, said, "Many more studies need to be done but I think this will be a step to an effective vaccine" (Guardian, 5/20).
Officials of the Botswana Harvard Institute Partnership for HIV Research and Education announced on Monday that researchers will begin trials of an HIV vaccine to determine healthy adults' immune response, the Associated Press reports. The vaccine, EP HIV-1090, which is made by San Diego, Calif.-based Epimmune, activates CD8+ T cells. The 18-month study will involve 42 HIV-negative volunteers from Botswana and the United States. Researchers will use participants with high levels of the protein human leukocyte antigen, or HLA, because it has been found to be the "most responsive" to the vaccine. Botswana, which has the highest HIV prevalence in the world, has said it plans to end new HIV infections in the country by 2016, the Associated Press reports (Motseta, Associated Press, 5/19).