Reports say that China granted approval to the country's first homegrown swine flu vaccine, which producer Sinovac says is effective after only one dose.
The decision could signal a major breakthrough in the global fight against A(H1N1) influenza, as most experts had assumed that two doses per person would be needed to provide adequate protection.
"The Sinovac H1N1 vaccine is officially approved," the head of the State Food and Drug Administration's registration department, Zhang Wei, told reporters.
"The completion of trials for Beijing Sinovac's vaccine has shown this vaccine to be very safe," the regulatory agency said in a brief statement ahead of a news conference.
Zhang said the SFDA was looking at applications from nine other companies developing vaccines against the A(H1N1) virus, with a decision expected by mid-September.
The World Health Organization (WHO) says at least 2,185 people have died after contracting swine flu, which has become the most prevalent strain of influenza. The virus has been detected in nearly every country in the world.
The UN health body has warned of a possible A(H1N1) vaccine shortage as the winter and the regular flu season approaches in the northern hemisphere.
"We know that supplies will be extremely limited for some months to come," WHO chief Margaret Chan said last month.
Countries in the northern hemisphere have so far ordered more than one billion doses of swine flu vaccine, according to the WHO.
More than two dozen pharmaceutical companies around the world are racing to test, produce and ship vaccines before the global pandemic enters an expected second wave.
Five of those firms will account for more than 80 percent of production: Sanofi-Pasteur in France, AstraZeneca and GlaxoSmithKline (GSK) in Britain, Baxter in the United States, and the Swiss group Novartis.
But Sinovac announced after clinical trials in mid-August that its one-dose formula had proven effective a major advantage as the vaccine would be easier to administer and available to more people.
"We have not found any negative side-effects it is safe and reliable," Sinovac president Yin Weidong told AFP in a recent interview at the company's Beijing headquarters.
Hans Troedsson, the outgoing WHO representative in China, said a one-dose vaccine would be "very important as it means we can vaccinate twice as many."
The Chinese government plans to vaccinate 65 million people, or five percent of the total population of 1.3 billion, before year's end.
Britain and France received their first batches of swine flu vaccine in late August.