HIV vaccine 'years off'
2008-08-05 13:04
Special Report
The South African government has announced a joint venture to reduce the cost of anti-retroviral drugs with a Swiss company.
Mexico City - Leaders in the quest for a vaccine against HIV acknowledged on Monday that their mission was dogged by many problems and cautioned that any breakthrough lay years in the future.
In a workshop at the International Aids Conference, they said the Aids pandemic would only be defeated by a preventative vaccine, rather than treating people who are already infected.
But they admitted there have been many setbacks in crafting such a shield, and some advocated a return to fundamentals, and said it is time to draw lessons from failure.
"Vaccine science is still more of an art than a science," said Tachi Yamada, executive director of the Bill and Melinda Gates Foundation's Global Health Programme, a major donor to the vaccine effort.
Gaps in knowledge, tools
Yamada pointed to fundamental gaps in knowledge about how the stealthy human immunodeficiency virus (HIV) subverts the immune system.
There also is a lack of key lab tools, including the right animal models for testing a candidate vaccine. Researchers had to rethink their approach on selecting which candidate should then be submitted to the long, exhausting three-phase trials on humans.
Meanwhile, Yamada said funding, collaboration and cooperation urgently had to be stepped up to avoid wasted or duplicated effort.
He said the arena must be opened up to smart, revolutionary ideas, and a new generation of vaccine researchers must be groomed.
"We need big investments for the future ... not only in the basic science of HIV prevention, but also in clinical trials for an HIV vaccine," Yamada said.
"We have to be unafraid to fail. ... The road to success begins with setbacks."
'At a critical crossroads'
Alan Bernstein, director of the Global HIV Vaccine Initiative, said the hunt was "at a critical crossroads" and any success could only be viewed as "long term."
"We have to be unafraid of failure. Science is not a straight line," said Bernstein.
Aids first emerged in 1981. Swift progress in identifying the virus that caused it unleashed early optimism that, like polio, measles and other viral threats of the past, a vaccine would quickly emerge.
To date, more than 25 million lives have been claimed by Aids and 33 million people are estimated to have HIV.
A safe, effective primer of the body's defences - the frontline antibody troops and the heavy artillery of the immune cells - remains far out of reach, however. Out of the 50 candidates that have been evaluated among humans, only two vaccines have made it through all three phases of trials, and both were rejected as quite ineffective.
- AFP