AstraZeneca’s nasal vaccine could still be a powerful future weapon in the fight against the Covid-19 pandemic despite disappointing recent trial results, said experts as quoted by news agency AFP.
The initial testing of the nasal-spray version of the Covid-19 vaccine developed by Oxford University researchers and AstraZeneca Plc, on human beings did not yield the desired protection.
The University of Oxford, in an official statement, said that the antibody response in the respiratory mucous membranes was seen in only a minority of participants in the trial, which was in the first of usually three phases of clinical testing.
Also, it also showed that the immune response measured in the blood was weaker than that from a shot-in-the-arm vaccination, the statement said as quoted by Reuters.
The British trial enrolled 30 previously unvaccinated participants as well as 12 volunteers, who had previously received a standard two-dose vaccine course by injection.
Sandy Douglas, chief investigator of the trial at Oxford University’s Jenner Institute said, “The nasal spray did not perform as well in this study as we had hoped.”
“We believe that delivery of vaccines to the nose and lungs remains a promising approach, but this study suggests there are likely to be challenged in making nasal sprays a reliable option,” she added.
However, researchers across the world had high hopes for the nasal spray Covid-19 vaccine because the method is believed to potentially prevent infection and not just disease as it may prompt an immune response directly in the airways, where the virus enters the body.
Nasal vaccines aim to build immunity in the mucous membrane that lines the nose and mouth by entering the body the same way as the virus. This could block people from getting infected in the first place.
China became the first country last month to approve a needle-free Covid-19 vaccine, an aerosolized mist inhaled through the nose and mouth using a nebulizer device, while India greenlit a homegrown nasal drop vaccine days later.
