September 22, 2007

Back to the Drawing Board with Merck AIDS Vaccine

Merck’s experimental AIDS vaccine fails

In a disappointing setback, a promising experimental AIDS vaccine failed to work in a large international test, leading the developer to halt the study. Merck & Co. said Friday that it is ending enrollment and vaccination of volunteers in the study, which was partly funded by the National Institutes of Health.

It was a high-profile failure in the daunting quest to develop a vaccine to prevent AIDS. Merck’s vaccine was the farthest along and was closely watched by experts in the field.

Officials at the company, based in Whitehouse Station, N.J., said 24 of 741 volunteers who got the vaccine in one segment of the experiment later became infected with HIV, the virus that causes AIDS. In a comparison group of volunteers who got dummy shots, 21 of 762 participants also became infected.

“It’s very disappointing news,” said Keith Gottesdiener, head of Merck’s clinical infectious disease and vaccine research group. “A major effort to develop a vaccine for HIV really did not deliver on the promise.”

Michael Zwick, an HIV researcher at Scripps Research Institute, said the vaccine’s failure is unfortunate. But he said it’s too soon to know if other vaccines using the same strategy would also fail. “It’s par for the course in the HIV field,” he said of the Merck result.

Damn.