Hundreds of thousands of people have taken experimental vaccines in China before clinical trials are completed, thanks to an emergency use programme launched in July to protect essential workers and limited groups of people facing high infection risk, raising safety concern among experts.

The 200,000 shots of a vaccine developed by CNBG's Wuhan unit, enough to inoculate 100,000 people, will be used to protect medical workers in the city, CNBG said in a social media post.

CNBG has two experimental coronavirus vaccines in the final-stage of clinical trials and both are included in the emergency use programme.

A CNBG executive said on Tuesday it was hoped that the two candidate vaccines get conditional regulatory approval for general public use this year.

CNBG is a subsidiary of state-owned China National Pharmaceutical Group (Sinopharm)..

(Reporting by Roxanne Liu and Tony Munroe in Beijing)