BEIJING -- A new COVID-19 vaccine developed by China's Sinopharm has recently been approved for clinical trials.

The new recombinant COVID-19 vaccine, developed by the National Vaccine & Serum Institute, a R&D center of Sinopharm's bioscience subsidiary the China National Biotec Group (CNBG), got approval from the National Medical Products Administration on April 9, the CNBG said on its official Weibo account on Saturday.

The vaccine is based on the structural features of the receptor binding domain (RBD) on the virus' spike protein (S-protein). It uses genetic engineering to grow harmless copies of the virus S-protein to induce neutralizing antibodies.

The company said that recombinant vaccine technology is mature and suitable for large-scale production. The production does not require facilities with high biosafety levels since the process does not involve live viruses.

The recombinant vaccine is the company's third COVID-19 vaccine. Last December, an inactivated vaccine developed by the Beijing Biological Products Institute Co., Ltd. under CNBG became the first Chinese COVID-19 vaccine to have conditional marketing authorization.

In February, another inactivated vaccine from the Wuhan Institute of Biological Products, a CNBG affiliate, was allowed to enter the market on a conditional basis.

More than 161.12 million doses of COVID-19 vaccines had been administered across China as of Friday, the National Health Commission said Saturday.