China became the first country to approve a needle-free, inhaled version of a Covid-19 vaccine made by Tianjin-based CanSino Biologics, pushing the company’s shares up as much as 14.5 per cent Monday morning in Hong Kong.

China’s National Medical Products Administration approved CanSino’s Ad5-nCoV for emergency use as a booster vaccine, the company said in a statement to the Hong Kong Stock Exchange on Sunday.

The vaccine is a new version of CanSino’s one-shot Covid drug, the first in the world to undergo human testing in March 2020 and which has been used in China, Mexico, Pakistan, Malaysia and Hungary after being rolled out in February 2021.

The inhaled version can stimulate cellular immunity and induce mucosal immunity to boost protection without intramuscular injection, CanSino said.

Companies are looking into developing inhaled versions of vaccines to stimulate antibodies in nasal and airway tissues to defend against coronavirus. They are needle-free and can be self-administered, broadening their appeal to vaccine-hesitant people and potentially easing pressure on health-care resources.

CanSino’s initial one-shot vaccine was found to be 66 per cent effective in preventing Covid-19 symptoms and 91 per cent effective against severe disease, but it trails vaccines from Sinovac Biotech Ltd. and state-owned Sinopharm Group in use outside China. Those two companies account for most of the 770 million doses China has sent to the rest of the world.

The vaccine, which uses a modified cold-causing virus to expose the immune system to the coronavirus, is similar to those developed by AstraZeneca Plc and Johnson & Johnson.