Sinovac Commences Phase II Clinical Trials For Pandemic Influenza Vaccine (H5N1)

Sinovac Biotech Ltd. (Amex: SVA),
a leading provider of biopharmaceutical products in China, today announced
that the China State Food and Drug Administration (SFDA) recently granted
Sinovac approval to commence the Phase II clinical trial of Panflu(TM), a
human use vaccine against the H5N1 strain of pandemic influenza virus.
Panflu was jointly developed with China CDC.


Two types of the H5N1 vaccine were approved by the SFDA to commence
clinical trials. The first type is the H5N1 whole viron inactivated vaccine
for which the Phase I clinical trial was completed in 2006. The Phase Ib
and II clinical trials for the H5N1 whole viron inactivated vaccine will be
conducted to further test the tolerance, safety, and immunogenicity and to
determine the dosage and inoculation schedule. During the Phase Ib and II
trials, the age groups of the participants will be enlarged by adding
youths and the elderly. The second type of vaccine is the H5N1 split viron
vaccine, for which the Phase I and II clinical trials will be conducted
continuously. The trials will focus on the vaccine's tolerance, safety, and
immunogenicity. It is anticipated that the Phase II clinical trials will
commence simultaneously for the two types of vaccines in order to determine
the vaccination dosage and inoculation schedule for drafting the
registration standards and specifications for the vaccine.



Mr. Weidong Yin, Chairman, President and CEO, stated, "The
authorization by the SFDA is an important milestone for Sinovac as we
continue to advance our pipeline of vaccines against human infectious
diseases. We are developing Panflu to vaccinate humans against H5N1 given
the significant concern that it may evolve into a virus capable of
human-to-human transmission. The team at Sinovac has recently completed the
production and testing of the vaccine that will be utilized in the trial.
We look forward to commencing enrollment in June 2007."



Sinovac commenced development of Panflu in February 2004 as part of the
global united battle to fight against pandemic influenza. In June 2006, the
results of phase I clinical trial were unblinded and showed good
immunogenicity and safety. On September 7, 2006, the results were published
in "The Lancet," a global renowned medical periodical, that provided
worldwide recognition for the Phase I clinical trial results of the
pandemic influenza vaccine (H5N1) developed by Chinese scientists.



About Sinovac



Sinovac Biotech Ltd. is a China-based biopharmaceutical company that
focuses on the research, development, manufacture and commercialization of
vaccines that protect against human infectious diseases. Sinovac's vaccines
include Healive(TM) (hepatitis A), Bilive(TM) (combined hepatitis A and B)
and Anflu(TM) (influenza). Sinovac is currently developing human vaccines
against the H5N1 strain of pandemic influenza, Japanese encephalitis and
SARS. Additional information about Sinovac is available on its website,
sinovac.


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Forward-looking statements involve inherent risks and uncertainties. A
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