Recombinant protein subunit COVID-19 vaccine products. [Photo/Institute of Microbiology of the Chinese Academy of Sciences]

Over 100 million people around the world have received a recombinant protein subunit COVID-19 vaccine developed by Anhui Zhifei Longcom Biopharmaceutical and the Chinese Academy of Sciences.

The vaccine is the world's first approved protein subunit vaccine. It uses purified pieces of the virus' protein to trigger an immune response, which can elicit stronger immune system protection in humans.

In response to the virus' continuous mutation, Anhui Zhifei Longcom Biopharmaceutical, the Hefei-based vaccine developer, has continued to increase its investment in the research and development of the second-generation vaccine that mainly targets the Delta and Omicron variants.

The cell bank for the company's second-generation recombinant protein subunit COVID-19 vaccine has been finished, and clinical application is planned to begin in July.