AstraZeneca and Oxford University scientists on Tuesday said that the initial testing of its nasal COVID-19 vaccine did not yield the desired protection.
In a statement issued on Tuesday, the University of Oxford said that an 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.
According to a report by the news agency Reuters, the immune response measured in the blood was weaker than that from a shot-in-the-arm vaccination.
Currently, scientists across the world have high hopes for the impact of nasal vaccines against COVID-19. The researchers believe that nasal vaccines have the potential of treating the virus and they can reportedly prompt an immune response directly in the airways, where the virus enters the body.
Meanwhile, countries like India and China have already developed and got approval from their respective countries’ regulatory authorities for their COVID-19 nasal vaccines.
Last month, India’s Health Ministry approved Bharat Biotech’s COVID-19 nasal spray vaccine while China’s CanSino Biologics Inc last month won emergency approval by the country’s drug regulator for an inhaled version of its COVID-19 vaccine.
Reportedly, the trial conducted by the British researchers enrolled 30 participants who were previously unvaccinated and 12 participants who had previously received a standard two-dose vaccine course by injection.
“The nasal spray did not perform as well in this study as we had hoped,” said Sandy Douglas, chief investigator of the trial at Oxford University’s Jenner Institute as quoted by Reuters.
“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.
(With inputs from Reuters)