Last November, HHS gave Sanofi-Aventis $120 million dollars to produce 3.7 million doses for the U.S. Strategic National Stockpile, which is on top of the $100 million they granted them in 2005 to develop a bird flu vaccine.
In March of 2006, an interim analysis of this vaccine published in the New England Journal of Medicine (NEJM) indicated that it required two shots, of 90 ug of antigen each, to produce an acceptable immune response in 54% of the test subjects. That is roughly 12 x's the antigen required for a standard flu shot, and considerably less effective as well.
Today, the FDA revealed that further study had reduced that number to only 45%.
Research is ongoing to see if an immune booster, an adjuvant, could be added to the vaccine to stretch the supplies, but right now, this has to be a bit disappointing to Sanofi and the FDA.
Tomorrow an advisory panel will vote on whether this vaccine is both `safe and effective'. A negative vote would not make the vaccine dead in the water, but later, when the FDA decides whether to license this vaccine, that vote will be taken into account as `expert advice'.
This from the AP.
The Associated Press
Published: February 26, 2007
WASHINGTON: The nation's first vaccine against bird flu is even less effective than previously thought, according to Food and Drug Administration documents released Monday.
In clinical trials, the two-shot series appears to provide protection to just 45 percent of adults who received the highest dosage of the Sanofi Aventis SA vaccine.
An earlier, interim analysis of the same study of the vaccine suggested it sparked a protective immune response in 54 percent of patients, when measured 28 days after getting the second shot. The New England Journal of Medicine published those results in March 2006.
The FDA released the more recent results, contained in company and agency documents, ahead of a Tuesday meeting where it will ask a panel of outside experts to review the vaccine. The agency is not required to follow the advice of its advisory committees, but usually does. The vaccine is the first against the H5N1 influenza strain to seek FDA approval.
The FDA said the 452-person study showed the vaccine against the potentially deadly bird-flu strain called H5N1 is safe, but it remained unclear whether it would be effective. Seasonal flu vaccines, for example, protect 75 percent to 90 percent of vaccinated adults younger than 65.