Swiss pharmaceutical giant Novartis said on Thursday that it has tested a new swine flu vaccine that may work after one dose while health chiefs hailed another one-dose drug developed in China.
Novartis said it was ready to produce one million doses of the vaccine before the end of the year in a bid to blunt the spread of swine flu which has already claimed at least 2,185 lives.
The drug giant said it was in talks to supply 35 countries with the new vaccine and had signed deals worth 979 millions dollars (685.4 million euros) to supply the US government.
China earlier Thursday granted approval to its first homegrown vaccine, which producer Sinovac says is effective after only one dose.
"The Sinovac (A)H1N1 vaccine is officially approved," said the head of the State Food and Drug Administration's drug registration department, Zhang Wei. Nine other Chinese companies were developing swine flu vaccines, he said.
The World Health Organisation praised China's research and said it could become the first country to protect its population against the pandemic.
Until now experts had maintained that two doses of vaccine would be necessary to protect against the A(H1N1) infection, straining limited vaccine supplies.
But clinical trials of the Novartis drug and of the Chinese vaccine showed that single doses could work, easing fears raised by the World Health Organisation (WHO) of a dangerous shortage of flu vaccine in the coming months.