Dr. Anthony S. Fauci said the government is ready to move ahead with ordering significantly more than the 2 million doses it acquired from a French vaccine maker before testing began earlier this year to jump start the U.S. vaccine stockpile in case the tests were successful.
Additional tests of the vaccine are being conducted on the elderly and children.
Preliminary data from the first 115 of the initial tests on 450 healthy adults showed an immune response that scientists believe is strong enough to protect against the avian influenza that's spreading among birds in Asia and Russia. Fauci said he expects analysis of data from the other 300 tests will show similar results.
"We're now, given these results, going to move ahead with ordering from the company additional dozes," Fauci said in a telephone interview. "I can't tell you exactly how many; that's going to depend on the production capability, but certainly it will be significantly more than the 2 million doses."
For the past year, government health officials have been hurrying to develop the vaccine because of fears that the avian influenza strain could change into one that could spread rapidly among humans throughout the world. While the strain has killed millions of birds, only about 50 humans have died from it and so far there has been no widespread transmission of the virus from one human to another.
Fauci predicted that the Food and Drug Administration could approve the new vaccine fairly quickly, since it's similar to prior seasonal flu vaccines the agency approves each year. The bigger problem is the lack of manufacturing capacity to produce the number of doses that may be needed.