HIV Vaccine Trial Volunteers Asked To Undergo Testing
HIV Vaccine Trial
Researchers have asked more than 3,000 people who participated in a trial of Merck'sexperimental HIV vaccine that was halted last month to undergoadditional testing to determine if they are at an increased risk ofHIV, Reuters reports (Fox, Reuters, 10/25).
Mercklast month announced that it had ended its Phase II trial, which beganin late 2004 and involved 3,000 HIV-negative volunteers, after itsexperimental vaccine failed to prevent HIV infection in participants orprove effective in delaying the progression of the virus to AIDS. Thetrial was stopped by the Data and Safety Monitoring Board, anindependent overseer. Some researchers have theorized that becauseHIV-positive people who have stronger CD4+ T-cell responses tend tofight the virus better, a vaccine that simulated a T-cell responsemight be able to control HIV/AIDS. The Merck vaccine was made from aweakened version of a common cold virus that served as a mode forproviding three synthetically produced genes from HIV, known as gag,pol and nef (Kaiser Daily HIV/AIDS Report, 10/25).
Researcherssaid that they do not have enough information to determine whether theparticipants who received the vaccine are more susceptible to HIV butthat initial information is worrisome. Officials from Merck and NIH's National Institute of Allergy and Infectious Diseasesemphasized that the vaccine could not result in HIV infection becauseit contains three synthetically produced genes that have "no way" to"reconstitute an intact virus."
According to NIAID, whichco-sponsored the trial, researchers are "analyzing available data tobetter understand if there may be an increased susceptibility toacquiring HIV infection among those volunteers who received thevaccine." Mark Feinberg, Merck's vice president for medical affairs andpublic health, in an e-mail said that researchers are analyzing a"tremendous amount of data."
Mitchell Warren of the AIDS Vaccine Advocacy Coalition,who was not involved in the study, said the global health community is"still trying to figure out what the data mean," adding that he hopesthe investigation will not deter people from participating in futureHIV vaccine trials. "How people understand this information is going tobe critical for this research to continue," Warren said (Reuters, 10/25).
Reprinted with permission from kaisernetwork.org. You can view theentire Kaiser DailyHIV/AIDS Report, search the archives, and sign up for email delivery at kaisernetwork.org/email . The Kaiser Daily HIV/AIDS Report ispublished for kaisernetwork.org, a free service of The Henry J. Kaiser FamilyFoundation.