Clinical Trial

US Drops Trial of AIDS Vaccine

US AIDS researchers are dropping plans to test one experimental vaccine in people, saying the high-profile failure of a Merck and Co. vaccine last year shows the need to do quicker, more focused studies. The National Institute of Allergy and Infectious Diseases (NIAID) part of the Government's National Institutes of Health, it was canceling the HIV vaccine study known as PAVE 100. However, NIAID believes the vaccine developed by its Vaccine Research Center (VRC) is scientifically intriguing and sufficiently different from previously tested HIV vaccines to consider testing it in a smaller, more focused clinical study.

It is the first demonstration of a new approach being taken by federal vaccine developers after a trial called STEP showed last year that Merck's vaccine may have raised the risk of infection among certain men- those who had pre-existing immune responses to the virus used in the vaccine and who were not circumcised.

The vaccine used a common virus known as an adenovirus to carry bits of the AIDS virus. The new vaccine being tested by the Partnership for AIDS Vaccine Evaluation, or PAVE, was designed to be given as three injections of HIV genetic material, followed with a final boost of adenovirus. Scientists had argued whether it was justified to go ahead with a large trial of a vaccine that could not be expected to protect people against infection in the hope of finding something in their biological responses that could help design a better vaccine down the road.

AIDS has killed 25 million people since it was first identified in the 1980s and it infects 33 million people globally. There is no cure although a cocktail of drugs can keep the infection suppressed.But while about 30 vaccines are being tested, none has come even close to preventing infection in people.

Reuters