A phase-one clinical trial for China's first recombinant subunit novel coronavirus vaccine completed recruiting participants on June 23, in the run-up to the testing of volunteers in Southwest China's Chongqing, according to local media reports.

Total of 30 volunteers signed up for the clinical trials at the Second Affiliated Hospital of Chongqing Medical University, hospital officials said.

As the second recombinant subunit COVID-19 vaccine to enter clinical trials worldwide, the vaccine was developed by Chongqing Zhifei Biological Products Co Ltd and the Institute of Microbiology at the Chinese Academy of Sciences.

On June 19, the vaccine was approved by the National Medical Products Administration to go into clinical trials.

The phase-one clinical trials were conducted in the Second Affiliated Hospital of Chongqing Medical University and the Beijing Chaoyang Hospital of Capital Medical University.

According to Ren Hong, president of the Chongqing hospital, a phase-one clinical trial is mainly to observe the safety of and tolerance of volunteers to the vaccine and data can be obtained within one month.

Thereafter, phase two and three clinical trials will be conducted according to the relevant situation and data.

Hospital officials said that after the vaccinations, the medical team will regularly follow up with the volunteers to see if they have any adverse reactions and whether antibodies can be produced in their bodies.

According to local media reports, in order to carry out the clinical trials smoothly, the hospital implemented strict reviews and preparations to ensure the rights and interests of all volunteers.