Sinovac Completes Construction of H1N1 Virus Seed Bank

Production of Seasonal Influenza Vaccine Is Nearly Completed

BEIJING, June 15 /PRNewswire-Asia/ — Sinovac Biotech Ltd. (NYSE Amex: SVA), a leading developer and provider of vaccines in China, announced today that it has completed construction of the H1N1 virus seed bank necessary to produce a virus antigen.

Sinovac received the seed virus from the US Center for Disease Control (CDC) on June 8, 2009 and started the H1N1 vaccine production on the same day. Sinovac expects to complete production of the first batch and initiate clinical trials of an H1N1 vaccine by the end of July 2009.

Mr. Weidong Yin, Chairman, President and CEO of Sinovac, commented, “On June 11, 2009, the World Health Organization declared the H1N1 virus a pandemic influenza outbreak. Having completed the construction of our virus seed bank, our H1N1 vaccine production remains on track and we look forward to initiating clinical trials by the end of next month. Sinovac’s rapid response to the newly emerged disease outbreak demonstrates the Company’s resources and capabilities for vaccine production and highlights our commitment to protect the public from virus transmission through the timely supply of vaccines.”

Sinovac’s production of Anflu for the 2009/2010 Northern Hemisphere influenza season is nearly completed. The production of H1N1 vaccine will not affect its production and launch of the seasonal flu vaccine for this coming flu season.

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 vaccine products include Healive(R) (hepatitis A), Bilive(R) (combined hepatitis A and B), and Anflu(R) (influenza). Panflu(TM), Sinovac’s pandemic influenza vaccine (H5N1), has already been approved for government stockpiling. Sinovac is developing vaccines for enterovirus 71, universal pandemic influenza, Japanese encephalitis vaccine, and human rabies vaccine. Its wholly owned subsidiary, Tangshan Yian, is conducting field trials for independently developed inactivated animal rabies vaccines.

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.

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

    Investors:
    Amy Glynn/Sara Pellegrino
    The Ruth Group
    Tel:  +1-646-536-7023/7002
    Email: aglynn@theruthgroup.com
    spellegrino@theruthgroup.com

    Media
    Janine McCargo
    The Ruth Group
    Tel:  656-536-7033
    Email:  jmccargo@theruthgroup.com

SOURCE Sinovac Biotech Ltd.