Sinovac Reports Positive Preliminary Phase II Clinical Trial Results for EV71 Vaccine Against Hand, Foot and Mouth Disease

BEIJING, November 9, 2011 /PRNewswire-Asia/ -- Sinovac Biotech Ltd. (NASDAQ: SVA), a leading provider of biopharmaceutical products in China, announced today the positive top-line results from its phase II clinical trial for its proprietary inactivated vaccine against human enterovirus 71 (EV71), which causes hand, foot and mouth disease (HFMD). The preliminary Phase II results for the EV71 vaccine showed a good immunogenicity and a favorable safety profile with no vaccine-related serious adverse event.

The phase II trial was designed as a single center, randomization, double blinded, and placebo controlled study and enrolled 540 healthy volunteers, comprised of infants from six months to thirty-five months old. OnNovember 8, 2011, the unblinding conference for the phase II clinical data was held under the supervision from the Data Safety and Monitoring Committee (DSMC), and was attended by experts from the China State Food and Drug Administration (SFDA) and the China CDC. The phase II clinical results have provided the reference data for phase III clinical trial, including the vaccination schedule and dosage selection, based on which the proper dosage can be selected to enter into the phase III clinical trial. The purpose for the phase III clinical trial is to evaluate the efficacy of protection against HFMD caused by EV71 and is designed as a multi-center, randomized, double-blinded and control study.

Dr. Weidong Yin, Chairman and CEO, remarked, "The positive phase II results are the significant milestone in the development of our EV71 vaccine to address a significant unmet medical need in those area, where the young children are under the high risk of infection. Based on the phase II results, the proper dosage level can be selected to be utilized in the phase III clinical trial. We have started the preparation work for the phase III clinical trial, including determining the phase III clinical trial proposal, selecting the clinical sites and preparing for the vaccines to be used in phase III clinical trial. We anticipate commencing the phase III clinical trial in the coming months, and aim to complete it in one year."

In parallel to the clinical development, Sinovac's engineering team is working on setting up a dedicated manufacturing facility for its EV71 vaccine and aims to complete the construction and GMP Certification in 2013.

About EV71

Enterovirus 71, or EV71, causes Hand, Foot, and Mouth Disease (or HFMD). More than 90% of the reported cases occur in children under five years old. HFMD is a common and usually mild childhood disease. Since 1997, the number of reported HFMD cases associated with severe neurological symptoms caused by EV71 and fatalities has increased significantly across the Asia-Pacific region. Outbreaks have been reported inVietnam (2011) Malaysia (1997), Taiwan (1998, 2000 & 2001), mainland China (1998-2008), Australia (1999) and Singapore (2000). No specific treatment for this enterovirus infection and no vaccine are currently available.

HFMD represent a very serious problem in China, some other Asian countries and other areas in recent years given that no vaccine and specific treatment is currently available to protect against this disease. EV71 represents a significant health threat to children as a growing number of HFMD cases have been reported in parts of Asia, including mainland China, Vietnam, Hong Kong, Singapore, South Korea, and Taiwan. According to the Chinese Ministry of Health's data available for the period from January 1 to September 30, 2011, the disease caused 399 deaths in China and over 1.2 million HFMD infection cases during the nine-month period, as reported by health authorities. In 2010, there were over 1.7 million reported EV71 infectious cases with over 800 fatal cases. In August of 2011, over 32,000 HFMD infectious cases were reported inVietnam with 81 deaths. HFMD is common among infants and children, as most of the recently reported cases have occurred in children under five years of age.

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 including hepatitis A, seasonal influenza, H5N1 (bird flu) pandemic influenza and H1N1 influenza. In 2009, Sinovac was the first company worldwide to receive approval for its H1N1 influenza vaccine, PANFLU.1, and has received orders from the Chinese Central Government pursuit to the government stockpiling program. The Company is developing a number of new vaccine products, including vaccines for pneumococcal conjugate, enterovirus 71 (EV71) (against Hand, Foot & Mouth Disease), pneumococcal polysaccharides, human rabies, HIB, rotavirus and epidemic meningitis, chickenpox and mumps & rubella. Its wholly owned subsidiary, Tangshan Yian, is focusing on the research, development, manufacturing and commercialization of animal vaccines, and has launched its internally developed inactivated rabies vaccine in China.

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 Yang/Chris Lee
Sinovac Biotech Ltd.
Tel: +86-10-8279-9871/9659
Fax: +86-10-6296-6910
Email: ir@sinovac.com

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The Ruth Group
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Email: scarrington@theruthgroup.com 
aglynn@theruthgroup.com

Media
Victoria Aguiar
The Ruth Group
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