Chinese vaccine maker Sinovac Biotech Ltd put its H1N1
vaccine through its first clinical trial last week, as pharmaceutical firms
race to put vaccines for the new flu virus into commercial production.
A total of 1,600 volunteers, aged from three to 60 years old, were
given their first shot. They will get a second one in 21 days.
Three types of H1N1 vaccine -- split virus vaccine, split virus vaccine
with adjuvant, and whole virus vaccine with adjuvant -- with antigen dosage
ranging from 5 to 30 microgrammes per dose were being tested.
Adjuvants are substances that help boost the immune response to a
vaccine.
The human body's clinical response and the amount of antibody each type
of vaccine triggers will be recorded during the testing process.
Yin Weidong, general manager of Sinovac, said the purpose of the trial
was to work out the right dosage.
Sinovac will use as little antigen, or active ingredient, as possible
to reduce the cost of the vaccine so as to make sure it can be used on more
people in China.
"Through the clinical trial, we can work out the right dosage to
use. We want to use as little antigen as possible. Of course, we must make
sure of the safety of the vaccine first. Low dosages of antigen must be based
on safety. There is no other way. First you must ensure the safety of the
vaccine, then you can think about using as little antigen as possible to
produce as many doses of vaccine as possible," said Yin.
He expected the cost of each dose to be around 30 RMB (4.30 US
dollars), which is half the price of vaccines produced in developed
countries.
The company will be able to kickstart mass production of the vaccine
once the clinical trials finish in mid September, Yin said.
China has recorded about 2,295 cases of H1N1, although there have been
no deaths, and is eager to prevent the disease from spreading among the wider
population.
Experts worry that if the disease becomes prevalent in China, with its
huge population and uneven health services, it could mutate into something
easily transmissible and far more deadly.
"If we are not sure about how the pandemic happened and in which
pattern it will develop, it is very difficult to develop and use vaccines. We
don't know which part of the population and which part of the country needs to
be vaccinated. That is what I am concerned about," said Yin.
The company has received an order for five million doses from the
Chinese government, according to Yin.
Sinovac applied the techniques it used in designing a vaccine against
the more lethal H5N1 bird flu virus to produce its H1N1 vaccine, after it
received a H1N1 strain from the U.S. Centers for Disease Control and
Prevention.
The clinical trial was supervised by the Beijing Municipal Centers for
Disease and Prevention.
Another Chinese pharmaceutical company Hualan Biological Engineering
Inc. also began a clinical test for its H1N1 vaccine on over 2,000
volunteers.
H1N1 pandemic flu has spread to some 160 countries and killed about 800
people since it first broke out in March, and needs to be watched carefully in
case it mutates and becomes more severe in winter, the World Health
Organisation said last week.
ENDS."
http://rtv.rtrlondon.co.uk/2009-07-28/33...
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