Competing antibodies may have limited the protection achieved in HIV vaccine trial in Thailand

Tuesday, May 6, 2014

DURHAM, N.C. – Continuing analysis of an HIV vaccine trial undertaken in Thailand is yielding additional information about how immune responses were triggered and why the vaccine did not protect more people.
 
In a study appearing May 6, 2013, in the journal Proceedings of the National Academy of Sciences, an international team of researchers led by the Duke Human Vaccine Institute describe a previously unknown interaction between antibodies that worked to block the vaccine’s protective powers.
 
The vaccine trial, known as RV144, used two investigational vaccines in combination, resulting in an unprecedented 31 percent protection rate among participants. While encouraging, that rate fell short of the minimum needed for public health use. However, additional analyses of the trial’s data are yielding a trove of information about the virus and its potential vulnerabilities.
 
Last year, Duke researchers published a study in the New England Journal of Medicine that detailed clues to why the vaccine tested in the RV144 trial protected some volunteers. 
 
In the current analysis, study authors, led by Georgia D. Tomaras, PhD, director of the Laboratory of Immune Responses and Virology at DHVI, explored the inverse relationship that helps explain why the vaccine may have failed to protect more of the participants ...

Read the full story: http://corporate.dukemedicine.org/news_and_publications/news_office/news/competing-antibodies-may-have-limited-the-protection-achieved-in-hiv-vaccine-trial-in-thailand