China has approved three COVID-19 vaccine candidates for clinical trials, said an official with the Ministry of Science and Technology (MOST) on Tuesday reports Xinhua.

An adenovirus vector vaccine, developed by a research team led by Chen Wei, an academician with the Chinese Academy of Engineering and a researcher at the Institute of Military Medicine under the Academy of Military Sciences, was the first to be approved to enter clinical trials, said Wu Yuanbin, director-general of science and technology for social development with the MOST, at a press conference.

China says its scientists have moved a step closer toward developing a vaccine against the coronavirus.

Wu Yuanbin, a senior official at China's Ministry of Science and Technology, said at a news conference on Tuesday that a vaccine developed by a Chinese research team cleared the safety screening phase of its clinical trial in March.

Wu said it is the world's first coronavirus vaccine to move to the second phase of a three-phase clinical trial. In the second phase, the vaccine will be examined mainly for its effectiveness.

According to Xinhua, the team is led by Chen Wei, a researcher at the Institute of Military Medicine under the Academy of Military Sciences.

The vaccine is designed to use another virus to carry genetic material. The academy is now inviting people who wish to become volunteers for conducting the new phase.

Two Chinese firms, state-run Wuhan Institute of Biological Products, and privately run Sinovac Research and Development are also each developing vaccines.

The Chinese government reportedly approved their vaccines for clinical trials this month.

Wu said others are also preparing to file for government approvals through next month.