Sinovac Biotech Ltd. was incorporated in Antigua and Barbuda on March 1, 1999. It is a bio-high-tech enterprise headquartered in Beijing. The company is principally engaged in the research, development, manufacture and protection of vaccines against infectious diseases. The company has also developed the world's first inactivated SARS coronavirus vaccine (completed Phase I clinical study), China's first pandemic influenza (H5N1) vaccine, and the world's first H1N1 influenza vaccine, contributing to disease prevention and control in China and the world. The company is developing a series of new products, including Sabin strain inactivated polio vaccine, 23-valent pneumococcal polysaccharide vaccine, new coronavirus inactivated vaccine and multiple combination vaccines.