An elderly person is being inoculated at Yongdinglu sub-district of Haidian district in Beijing, China, March 14, 2021. A PHOTO XINHUA An inhalable COVID 19 vaccine developed by CanSino Biologics has been shown to be safe, effective and safe for the production of neutralizing antibodies, making it a possible booster shot option that is easy to administer, according to a study published in The Lancet Respiratory Medicine.
The vaccine is an aerosol version of Convidecia, a single-dose adenovirus-based viral vector vaccine that was granted emergency use listing by the World Health Organization last week. It was the 11th COVID 19 vaccine validated by the WHO and found to have 64 percent efficacy against symptomatic disease and 92 percent against severe COVID- 19.
The study published on Friday examines the safety and immune response of the inhalable vaccine when used as a booster shot for people who have received two doses of inactivated vaccine.
The study found that the new vaccine is safe for a total of 420 participants and can produce significantly higher levels of neutralizing antibodies in volunteers compared with those who received an inactivated vaccine as a booster shot.
The most common adverse reactions for the group included fatigue, headaches and fever, according to the study. The participants who received the inhalable vaccine as a booster had generated an 18.4 to 26.4 times higher level of neutralizing antibodies.
The study said that the inhalable vaccine only requires about one-fifth to two-fifths of the dosage in the original Convidecia vaccine to trigger an immune response.
It can bolster the immune response in cells that form the mucous membrane in the upper airways, which is the first line of defense against respiratory viruses. The vaccine delivered through intramuscular injections lacks respiratory mucosal protection.
The researchers pointed out several limitations of their study, such as a relatively small sample size and a lack of data on whether the neutralizing antibody produced could work on variants of the virus, including the Omicron strains.
The inhalable vaccine's ability to provoke an immune response may not always translate to higher efficacy against symptomatic COVID-19 and community transmission compared to boosting through other types of vaccines, they said.
The company said in a statement that it is planning to conduct an efficacy trial of the inhalable vaccine as a booster dose in Mexico, and will allow the process for the vaccine to be approved for emergency use or conditional market approval.
The use of an inhalable vaccine will reduce the cost of inoculation, improve efficiency and build up an immunity barrier against COVID 19, it said.
The aim of the aerosol vaccine is to make inoculation easier and more acceptable, particularly for children and people who are afraid of needles, said Zhu Tao, chief scientist of the company.
The recipient inhales it through a straw, holds it in for about five seconds and then slowly exhales it in a sealed cup.
The process takes about 10 seconds to complete, according to Zhu.
Since its debut last year in a convention in Hainan, Chinese netizens have dubbed the technology a vaccine in a cup.