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SINOVAC Quadrivalent Influenza Vaccine Approved for Expanded Use From 6 Months of Age
BEIJING, Oct. 10, 2025 – SINOVAC's quadrivalent influenza vaccine, produced by its subsidiary Beijing Sinovac Biological Products Co., Ltd., has received approval from the National Medical Products Administration (NMPA) for an age expansion to include infants and young children aged 6 to 35 months. With this approval，the vaccine is now approved for all populations aged six months and older, providing a standardized 0.5ml dose across all age groups to simplify administration and improve vaccination accessibility in China.
Infants and young children aged 6–35 months are recognized as a higher-risk group for influenza-related complications. Vaccination is a widely accepted preventive measure to reduce the risk of influenza and associated complications. Household transmission is also considered an important contributor to influenza spread, and vaccination of eligible household members and caregivers is commonly recommended within public health guidance.
A Phase III clinical study evaluating the quadrivalent vaccine in infants aged 6 to 35 months demonstrated that a two-dose schedule (Days 0 and 28) of the 0.5mL formulation induced a superior immune response compared to two 0.25mL doses of a trivalent influenza vaccine. The study reported no significant difference in adverse reaction rates between the quadrivalent and trivalent groups, indicating that the increased antigen dosage did not elevate safety risks. Additionally, the incidence of adverse reactions after the second dose was lower than that of the first, suggesting favorable tolerability.
To date, SINOVAC's seasonal influenza vaccines have been widely used in nearly 20 countries and regions globally. The Company maintains international standards in manufacturing and quality control to ensure high immunogenicity and a favorable safety profile for its global vaccine supply.
About SINOVAC
Sinovac Biotech Ltd. (SINOVAC) is a China-based global biopharmaceutical company, with a mission of "supply vaccines to eliminate human diseases", the company specializes in the research, development, manufacturing and commercialization of vaccines and related biological products that protect against human infectious diseases.
The company's diversified portfolio includes vaccines for influenza, viral hepatitis, varicella, Hand-Foot-Mouth disease (HFMD), poliomyelitis, pneumococcal disease, etc., of which 3 vaccines have been prequalified by WHO, including inactivated hepatitis A vaccine Healive®, Sabin-strain inactivated polio vaccine (sIPV), and varicella vaccine.
SINOVAC has a leading edge in developing vaccines to combat infectious disease outbreaks and was among the first to initiate R&D during major public health emergencies, including SARS, H5N1, H1N1, and COVID-19. The company developed the world's first inactivated SARS vaccine (Phase I completed), China's first H5N1 influenza vaccine (Panflu®), the world's first H1N1 influenza vaccine (Panflu.1®), and CoronaVac®, the most widely used inactivated COVID-19 vaccine globally.
Beyond its marketed portfolio, the company is advancing a robust pipeline that includes combination vaccines,recombinant protein vaccines and next-generation platforms such as mRNA technologies and antibodies.
With a long-standing commitment to innovation and global health, SINOVAC is expanding its global footprint by strengthening partnerships with research institutions, international organizations, and local partners. Through broader market presence, technological cooperation, and localized production, the company aims to accelerate vaccine development and supply, enhance regional access to high-quality products, and better address unmet medical needs while improving preparedness for future pandemics.
For more information, please see the Company’s website at www.sinovac.com.