Sinovac Amends Shareholder Rights Plan

Sinovac Biotech Ltd. ("Sinovac" or the "Company") (NASDAQ: SVA), a leading provider of biopharmaceutical products in China, today announced that its board of directors has amended its shareholder rights plan. The amendment extends the expiration date of the plan from February 22, 2024 to February 22, 2025.

About SINOVAC

Sinovac Biotech Ltd. (SINOVAC) is a China-based biopharmaceutical company that focuses on the R&D, manufacturing, and commercialization of biomedical products that protect against human infectious diseases.

SINOVAC's product portfolio includes vaccines against COVID-19, enterovirus 71 (EV71) infected hand-foot-mouth disease (HFMD), hepatitis A, varicella, influenza, poliomyelitis, pneumococcal disease, mumps, etc.

The COVID-19 vaccine, CoronaVac^®, has been approved for use in more than 60 countries and regions worldwide. The hepatitis A vaccine, Healive^®, passed WHO prequalification requirements in 2017. The EV71 vaccine, Inlive^®, is an innovative vaccine under "Category 1 Preventative Biological Products" and commercialized in China in 2016. In 2022, SINOVAC's Sabin-strain inactivated polio vaccine (sIPV) and varicella vaccine were prequalified by the WHO.

SINOVAC was the first company to be granted approval for its H1N1 influenza vaccine Panflu.1^®, which has supplied the Chinese government's vaccination campaign and stockpiling program. The Company is also the only supplier of the H5N1 pandemic influenza vaccine, Panflu^®, to the Chinese government stockpiling program.

SINOVAC continually dedicates itself to pipeline development including but not limited to new technology, new vaccines as well as other biomedical products. We will constantly explore global opportunities of strategic expansion.

For more information, please visit the Company's website at www.sinovac.com.