A total of 29 million confirmed cases of Covid-19 have been reported worldwide, with the number of deaths approaching one million: 925,000 to be exact, as of 15 September 2020. With these numbers continuing to rise, new approaches are being explored for a therapeutic or vaccine for Covid-19. This now includes nasal sprays for delivering a vaccine. Approval was granted in China on 9 September 2020, to initiate a Phase I clinical trial with a nasal spray vaccine against Covid-19. The intranasal spray is being co-developed by Beijing Wantai Biological Pharmacy Enterprise with researchers from Xiamen University and Hong Kong University. This vaccine candidate is also the first of its kind to receive authorisation from the China National Medical Products Administration. The nasal spray vaccine, which consists of weakened flu viruses, including H1N1, H3N2, and B, with genetic segments of the Covid-19 spike protein, mimics the infection of respiratory viruses and stimulates the immune response. The Phase I clinical trial is expected to begin in November 2020, enrolling 100 patients, and will take at least a year to complete.
Why this approach? Nasal sprays are liquid medicines delivered through the nose, which is far less invasive for the recipient than the intramuscular injection alternative. The drug can be rapidly absorbed through the nasal mucosa since it is supplied by many blood vessels. It is also expected to be easier to mass-produce and distribute because it will utilise the same production technology as the influenza vaccine.
This is just one of many vaccine candidates currently being tested to protect against Covid-19. This is not the only nasal vaccine being developed. Currently, there are five vaccines in development for Covid-19 with intranasal routes of administration with spike protein in the formulation. As the number of cases and deaths continue to rise, so does the research and efforts to find a vaccine. This latest approval just shows that every approach and option is being considered to end this ongoing pandemic.