A potential HIV vaccine that recently failed a clinical trial in the United States may increase some people's chance of catching the virus that causes AIDS.
Top government and drug industry scientists are currently reviewing data from the trial, which unexpectedly found more HIV infections among study participants who had previously been exposed to a common virus called adenovirus, The Washington Times reported Monday.
"We're trying very hard to understand the data more fully and completely," says Nalini Saligram, a spokeswoman for Merck, co-sponsor of the STEP vaccine trial.
Dr. Anthony S. Fauci, director of the National Institute of Allergy and Infectious Disease, called the trial results "both disappointing and puzzling."
The trial involved 3,000 participants between the ages of 18 and 45 who were at risk of HIV infection based on their behavior.
It ended in September after researchers determined the vaccine failed to decrease either the chance of HIV infection or the amount of virus in people who became infected while taking it.
Copyright 2007 by United Press International
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