SHANGHAI — An experimental inhaled COVID-19 vaccine could provide stronger protection than injectable shots, even with a lower dosage, a provincial health official said during a biopharma conference Tuesday.

Zhu Fengcai, the deputy head of the Center for Disease Control in the eastern Jiangsu province, explained how inhaled vaccines work directly at the virus’ point of entry, giving them the advantage of inducing an immune response at the mucosal surfaces of the nose and mouth, where the coronavirus is most likely to invade the body.

“It’s like drinking a coke,” Zhu said, speaking at the International Biopharma Industry Week in Shanghai, showing an illustration of a person covering their mouth with a plastic cup. “But instead of a liquid, you take in gas. It’s that easy.”

While discussions on nasal sprays and inhaled vaccines for use against COVID-19 have gained momentum, such methods have yet to take off globally. Though China hasn’t approved the inhaled vaccine, it has green-lighted the injection version of the shot developed by domestic vaccine maker CanSino Biologics — dubbed Ad5-nCOV — for emergency use.

Two small-scale human studies of the inhaled vaccine in China have shown promising results, with one study published in the British medical journal, The Lancet. Some 300 adults who took the inhaled vaccine, which had a fifth of the dosage contained in the injection version, induced a similar immune response.

However, the effectiveness of CanSino’s inhaled vaccine in preventing COVID-19 remains unclear, as it has yet to be tested in large-scale phase III trials.

“Vaccines alone can’t stop the spread of (COVID-19),” Zhu said, referring specifically to the outbreak that started from the city of Nanjing and spread to several places over the summer. “The most important use of the vaccine is to prevent severe disease and death. We still need to wear face masks and practice social distancing.”

Editor: Bibek Bhandari.

(Header image: An experimental inhaled COVID-19 vaccine shown during the International Biopharma Industry Week in Shanghai, Oct. 12, 2021. Ye Ruolin/Sixth Tone)