Beijing: 

China's drug authority has approved for clinical trials an inhaled Covid-19 vaccine co-developed by domestic firm CanSino Biologics, the company said in a filing on Tuesday.

The move comes after the National Medical Products Administration gave another CanSino vaccine conditional approval last month, allowing it for public use.

China currently has five coronavirus vaccines that have been given conditional market approval or allowed for emergency use, but none of these are administered by inhalation.

CanSino said in its latest filing on the Hong Kong stock exchange that the vaccine for inhalation was jointly developed by the company and the Beijing Institute of Biotechnology, adding that their clinical trial application got the green light on Monday.

But it warned that the vaccine's safety and efficacy remain "subject to confirmation" in trials.

As of March 20, China had administered 74.96 million coronavirus vaccine doses, according to Our World in Data, a collaboration between Oxford University and a charity.

Chinese embassies in some countries including the United States, Australia and India have issued notices saying the country will open visa applications to select people who have taken a China-made jab.

The vaccine for inhalation was jointly developed by CanSino and Beijing Institute of Biotechnology.