Sinovac Submits Clinical Trial Application for Mumps Vaccine to SFDA

BEIJING, May 5 /PRNewswire-Asia/ — Sinovac Biotech Ltd. (Nasdaq: SVA), a
leading China-based vaccine manufacturer, announced today that its 30%-owned
joint venture, Sinovac Dalian, has submitted an application to China’s State
Food and Drug Administration (SFDA) to commence human clinical trials for its
mumps vaccine. The proprietary mumps vaccine developed by Sinovac Dalian
represents not only the first live attenuated vaccine for which Sinovac has
filed a clinical trial application, but also the first candidate from the
joint venture’s pipeline for which a clinical trial application has been
submitted to and accepted by the SFDA since the formation of the joint venture
in January 2010.

Currently, the R&D process for the rubella vaccine is progressing on
schedule and the development plan for measles vaccine is underway.
Post-approval of a mumps vaccine, the Company plans to commercialize a
combination measles, mumps and rubella (MMR) vaccine that will be eligible for
the government purchasing program. In February 2008, the Chinese government
included the MMR vaccine in its national expanded program for immunization.
Based on the number of children within the target age group of this program,
the annual market demand in China for the MMR vaccine is estimated to be
approximately 30 million doses. This projected market demand exceeds the 12.5
million doses of the MMR vaccine that were approved and released in China in
2009.

Mr. Weidong Yin, Chairman, President and CEO of Sinovac, commented, “This
submission to the SFDA for approval to commence clinical trials for the mumps
vaccine is a major milestone for us as it is the first live attenuated vaccine
that our company has brought to this point. In addition, the mumps vaccine is
the first candidate from Sinovac Dalian’s development pipeline to be submitted
for human clinical trials. Sinovac Dalian will continue to bring strategic
value to our company and its stakeholders as this program moves toward
commercialization given that the manufacturing facility for the mumps vaccine
is already in place and we are prepared to commence manufacturing upon receipt
of the production license from the SFDA. After we receive approval for the
clinical trial application from the SFDA, we look forward to commencing the
clinical trials for the mumps vaccine and moving towards the commercialization
of a mumps vaccine as the first step and then a MMR combination vaccine in the
coming years.”

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
commercialized vaccine products include Healive(R) (hepatitis A), Bilive(R)
(combined hepatitis A and B), Anflu(R) (seasonal influenza), Panflu(TM)
(pandemic influenza (H5N1)), and Panflu.1(TM) (pandemic influenza A (H1N1)).
Sinovac is developing vaccines for enterovirus 71, universal pandemic
influenza, pneumococcal infection, Japanese encephalitis, and human rabies.
Its wholly owned subsidiary, Tangshan Yian, is conducting field trials for
independently developed inactivated animal rabies vaccines. Its 30%-owned
joint venture, Sinovac Dalian, focuses on the research, development,
manufacturing and commercialization of vaccines, such as rabies, chickenpox,
mumps and rubella vaccines for human use.

About Mumps Vaccine in China

According to the batch release data furnished by China’s National
Institute for the Control of Pharmaceutical Biological Products (NICPBP), the
total released quantity in 2009 for mumps related vaccines, inclusive of the
MMR, MM(measles and mumps combined), single measles, single mumps and single
rubella vaccines, was 115 million doses. According to NICPBP batch lot
release records, 12.5 million doses of MMR were approved and released in China
in 2009, compared to 7.0 million doses in 2008.

Safe Harbor Statement

This announcement contains forward-looking statements. These statements
are made under the “safe harbor” provisions of the U.S. Private Securities
Litigation Reform Act of 1995. These forward-looking statements can be
identified by words or phrases such as “will,” “expects,” “anticipates,”
“future,” “intends,” “plans,” “believes,” “estimates” and similar statements.
Among other things, the business outlook and quotations from management in
this press release contain forward-looking statements. Statements that are not
historical facts, including statements about Sinovac’s beliefs and
expectations, are forward-looking statements. Forward-looking statements
involve inherent risks and uncertainties. A number of important factors could
cause actual results to differ materially from those contained in any
forward-looking statement. Sinovac does not undertake any obligation to update
any forward-looking statement, except as required under applicable law.

    For more information, please contact:

    Helen G. Yang
     Sinovac Biotech Ltd.
     Tel:  +86-10-8289-0088 x9871
     Fax:  +86-10-6296-6910
     Email: info@sinovac.com

    Investors:
     Amy Glynn/Stephanie Carrington
     The Ruth Group
     Tel:   +1-646-536-7023/7017
     Email: aglynn@theruthgroup.com
            scarrington@theruthgroup.com

    Media
     Janine McCargo
     The Ruth Group
     Tel:   +1-646-536-7033
     Email: jmccargo@theruthgroup.com

SOURCE Sinovac Biotech Ltd.