Voice of America News (10.03.11) - Wednesday, October 05,
An experimental HIV vaccine has produced a 90 percent immune
response in a small group of healthy human subjects,
researchers in Spain have reported.
The MVA-B vaccine is composed of bits of noninfectious HIV
genetic material, said the scientists from the Spanish
National Research Council's National Biotech Center. It is
designed to train the immune system to detect and fight
different components of HIV.
Mariano Esteban, lead scientist on the work, compared the
approach to showing a picture of HIV to the immune system's
"soldiers," who will then be ready to recognize and attack it
if it appears in the future.
In the clinical trial, the team worked with 30 HIV-negative
volunteers to determine whether a healthy immune system is
capable of reacting to the vaccine. Six subjects received a
placebo. Those who received the vaccine were in no danger of
contracting the virus because the four HIV genes used cannot
self-replicate. Eighty-five percent of those who got the
vaccine maintained a strong response to HIV for at least one
Esteban said the goal is for the vaccine to reduce HIV to "a
minor chronic infection."
The team's results are reported in two publications: in the
Journal of Virology, "The HIV/AIDS Vaccine Candidate MVA-B
Administered as a Single Immunogen in Humans Triggers Robust,
Polyfunctional and Selective Effector Memory T Cell Responses
to HIV-1 Antigens," (2011;doi:10.1128/JVI.05165-11); and in
Vaccine, "Safety and Immunogenicity of a Modified Pox Vector-
Based HIV/AIDS Vaccine Candidate Expressing Env, Gag, Pol and
Nef Proteins of HIV-1 Subtype B (MVA-B) in Healthy HIV-1-
Uninfected Volunteers: A Phase I Clinical Trial (RISVAC02),"