China is seeking up to 500 volunteers for the second trial of a vaccine to
protect humans against the deadly bird flu virus after first-phase tests
indicated it was safe, state media said.
The second round of clinical tests would mainly aim to see for how long the
vaccine could protect the human body against the H5N1 virus, the Beijing Youth
Daily said, citing a doctor at the Sino-Japanese Friendship Hospital where the
trial would take place.
Results from the first round of trials, which ended in June, showed that the
120 people who were vaccinated had no serious adverse reactions, company
officials said this week.
The pool of volunteers for the second round was nearly four times the size of
that for the initial trials, but officials did not explain why.
As with last time, the volunteers needed to be healthy people aged between 18
and 65, hospital officials were quoted as saying. No children, people older than
65, or pregnant women would be accepted, they said.
The vaccine must undergo three phases of clinical trials before being allowed
on the market, Xinhua said.
The vaccine's manufacturer, Sinovac Biotech Limited, announced earlier this
week that it planned to produce 20 million vaccines annually within the next few
years, the Xinhua news agency said.
The company jointly developed the inoculation with China's Ministry of
Science and Technology and the Center for Disease Control and Prevention.
About a dozen companies were conducting clinical trials on bird flu vaccines
worldwide, Xinhua said.
The H5N1 bird flu virus is mainly spread among poultry and occasionally from
poultry to humans. But experts fear it could mutate into a form easily
transmitted between humans.
The bird flu virus has killed about 140 people, mostly in Asia, since 2003.
It has infected 21 people in China since then, killing 14, according to official
figures.
