LONDON -- A British company reported yesterday it had achieved the best results ever seen on an experimental human vaccine for bird flu and said mass production might be possible by 2007.
A global health official called GlaxoSmithKline's early results ``an exciting piece of science." If further tests are as promising, it would be a major step in the frustrating campaign to protect people from a possible deadly flu pandemic.
The US government's chief infectious disease scientist also was very optimistic.
``The data are really very impressive," said Dr. Anthony Fauci, director of the National Institute of Allergy and Infectious Diseases. ``It changes the whole complexion of the issue that we have to face of getting enough vaccine for people who might need it in a pandemic."
Glaxo's results came from tests on 400 people in Belgium, most of whom developed strong immune responses from very low doses of the prototype vaccine.
Success from wider tests of the vaccine could intensify competition with Sanofi-Aventis SA, whose vaccine unit, Sanofi Pasteur, reported disappointing results in March on its experimental product. It protected only about half of those who got two shots with a very high dose -- 90 micrograms of the key ingredient.
Glaxo said two shots of its vaccine provoked strong responses in more than 80 percent of people tested at lower doses than other experimental bird flu vaccines use. Some received as little as 3.8 micrograms, said Fauci, who has seen the test results.
The Glaxo vaccine includes an immune-system booster that allows it to use less of the main active ingredient, meaning that greater quantities could be produced if the H5N1 bird virus mutates into a form that spreads easily among people and causes a global epidemic. The vaccine uses an inactive version of the newer strain of H5N1, which was isolated in Indonesia last year.