The US government began a major overhaul of its effort to produce an Aids vaccine today, stressing basic scientific research after the failure of a key clinical trial last year.
Government officials at a summit with Aids scientists pledged to prioritize spending on lab work and animal tests rather than expensive, and thus far disappointing, clinical vaccine trials on humans.
"We need to turn the nob in the direction of discovery. That is unambiguous," said Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases, who convened the meeting outside of Washington.
"We really do need new and novel ideas."
The vaccine summit follows the failure last year of an experimental HIV vaccine developed by Merck & Co which had been widely touted as one of the best hopes in the field.
Clinical trials, however, indicated that the vaccine candidate did not protect against infection with the AIDS virus and might even have made recipients more susceptible, although how is not exactly clear.
Scientists said the surprising outcome of the Merck trials demonstrated how little HIV is understood after more than two decades of intensive research.
"Despite hundreds and hundreds of millions of dollars, the reality is that in 2008 an effective HIV/AIDS vaccine is beyond our grasp," said Warner Greene, a co-chair of the summit and professor of medicine at the University of California-San Francisco.
"There is no question in my mind that the HIV vaccine effort is in need of a major mid-course correction."