, VIENNA, Austria, Jul 20 – Scientists attending the International Aids conference have expressed optimism that a new HIV vaccine could be discovered soon.
United States National Institute of Allergy and Infectious Diseases Director Dr Anthony Fauci said on Monday that they were using specimens from a trial that was concluded in Thailand last year to find out the immune responses that made the vaccine dubbed RV144 protect some people from acquiring HIV infection.
“One of our key priorities right now is to build on the modest success announced last year from the Thai RV 144 trial. If we are able to find correlate from those studies then by mid next year, the path to a future vaccine improvement will be very clear,” he said.
The research in Thailand began in September 2003 when the screening started and then the first vaccination took place in October of the same year. About 16,400 Thai citizens received at least one dose of the vaccine or placebo, which is a simulated medical intervention that depends on the use of controlled and measured deception.
The study was sponsored by the US Army and showed that an investigational HIV vaccine regimen was safe and modestly effective with at least 31.2 percent efficacy at reducing the rate of HIV infection.
Results suggest that the vaccine regimen protected people at lower risk of infection and the protection appeared to decrease over time.
“If there is no correlate and it is likely that there will not be a clear correlate then we can still move the strategy into higher risk populations and potentially give vaccine more frequently. In the RV144 trial there was a hint that the efficacy early in the trial was higher than in the trial overall and certainly that is something we want to explore,” Dr Fauci said.
RV144 tested a prime-boost vaccine strategy that combined two vaccines based on strains of HIV that circulate in Thailand.
Billionaire philanthropist Bill Gates noted that the Thai trials were an indicator of “exciting developments in the field of vaccine.”
“We need to develop a range of prevention products because people have different needs and we also need to act fast when we get positive results,” he said.