FDA Okays Avian Flu Vaccine and Will Stockpile It, for Now

ROCKVILLE, Md., April 17 -- A vaccine against the H5N1 avian flu has been approved by the FDA.

With the approval, the FDA will buy the vaccine from its manufacturer, sanofi-pasteur, and stockpile it, the agency said. The will not be sold publicly.

In a clinical trial a year ago, the vaccine produced what investigators called a "neutralizing antibody responses typically associated with protection against influenza" in 54% of volunteers who were given two intramuscular doses of 90 mcg 28 days apart. (Avian Flu Vaccine Protective but Only at High Doses)

"The threat of an influenza pandemic is, at present, one of the most significant public health issues our nation and world faces," FDA Commissioner Andrew von Eschenbach, M.D., said in a statement.

"The approval of this vaccine is an important step forward in our protection against a pandemic," Dr. von Eschenbach said.

The H5N1 avian flu has only limited ability to infect humans, but it is regarded as a serious threat because it is widespread in birds and found in almost all areas of the world, except the Americas.

If it acquires the ability pass easily from person to person, experts think it could cause a new influenza pandemic. Indeed, as of April 11, there have been 291 human cases of H5N1 infections reported to the World Health Organization, 172 of them fatal.