A person in Britain became the first to get the swine flu vaccine about 10 days ago, he said.

Sanofi-Pasteur, which makes about 40 percent of the world's flu vaccines, expects to start testing its swine flu vaccine within days in the U.S. and Europe, according to spokesman Benoit Rungeard. Sanofi-Pasteur is a unit of Paris-based Sanofi-Aventis SA.

Since swine flu was declared to be a pandemic, or global outbreak, by the World Health Organization in June, pharmaceuticals have been racing to get their vaccines ready. Last month, Australian drugmaker CSL became the first vaccine maker to start testing its vaccine in humans in Australia.

"We initiated clinical trials about 10 days ago," Althoff said.

Half of Novartis' vaccines being tested are grown in chicken eggs, the traditional way of making flu vaccines, while the other half use a new cell-based technology.

The trial will test the vaccine's safety and whether one or two shots are necessary.

"Our assumption is that two doses will be required," Althoff said.

The vaccines being tested in Europe have an adjuvant, an ingredient used to boost the body's immune response. In the U.S., Althoff said Novartis will be testing both vaccines with and without adjuvants.