Thought Theater

HIV Vaccine Update genre: Little Red Ribbon-Hood

The following HIV vaccine information is reprinted from Kaiser Netwrok which can be found here. More and more experimental vaccines are in the testing and trials pipeline. An available vaccine is still a number of years away even if one of the many candidates were to be found effective.

The Wall Street Journal on Monday examined a procedure developed by a research team from Harvard Medical School and the Dutch biotechnology company Crucell that might deliver experimental HIV/AIDS vaccines using a modified common cold virus. NIH and Merck have developed two experimental AIDS vaccines, currently in trials, that attempt to use a modified version of the cold virus Adenovirus 5 "like a shuttle rocket carrying a payload of AIDS genes to spark an immune defense," according to the Journal.

About 40% to 50% of people in developed countries and 90% of people in Africa have been exposed and are immune to the Ad5 virus, which could hinder the vaccine's effectiveness by "blocking the virus before it delivers its payload," the Journal reports. To circumvent this, researchers used a procedure that modifies Ad5 to resemble a similar virus, Adenovirus 48, to which few people are immune. The Harvard and Crucell team in a letter published in the April 16 online version of the journal Nature reported that the procedure led to positive immune responses in monkeys, according to study author Dan Barouch of Harvard Medical School and Beth Israel Deaconess Medical Center.

Crucell Chief Scientific Officer Jaap Goudsmit said the vaccine procedure could begin human trials by late 2007, adding that the procedure potentially could be modified for vaccines for other diseases such as malaria and tuberculosis. "The proof of the pudding is always what happens in humans, but this is a promising start in the attempt to get around the problem of pre-existing immunity," Anthony Fauci, director of NIH's National Institute of Allergy and Infectious Diseases, said. The research on the procedure is funded by a $19.2 million NIH grant (Chase, Wall Street Journal, 4/17).