Some researchers are pointing to the need for an intranasal approach to vaccination in order to block the viral particles from gaining a foothold in the body at the point of entry – the nose.
As a push for additional boosters of the COVID-19 vaccines continues amidst concerns of new variants such as the omicron subvariant BA.2, some researchers are pointing to the need for an intranasal approach to vaccination. This approach has the benefit of blocking the viral particles from gaining a foothold in the body at the point of entry – the nose.
Research into intranasal approaches has been ongoing throughout the pandemic, even as the traditional injection has provided billions of people with some levels of protection against the original strains of the SARS-CoV-2 virus. In December, scientists from Yale University published a report in the journal Science Immunology that showed intranasal delivery gave greater protection against heterologous respiratory viruses in mice in comparison to the intramuscular injections, which are used to deliver the COVID-19 vaccines currently authorized for use.
The Washington Post reported that the National Institutes of Health and the Biomedical Advanced Research and Development Authority (BARDA) have been examining multiple next-generation vaccine concepts, including those delivered intranasally.
Robert Seder, chief of the cellular immunology section at the National Institute of Allergy & Infectious Diseases, told the Post that the intranasal approach would change the game against COVID due to its ability to halt the virus at the point of entry. Seder posited a scenario where a COVID variant as infectious as Omicron and one causing severe disease like the Delta variant could occur. He said people would want a potent vaccine to protect against such a threat. At NIAID, Seder and his colleagues are assessing intranasal vaccine approaches to determine which ones will be most effective against current and emerging COVID threats.
As BioSpace has previously reported, intranasal delivery is believed to be more effective in preventing disease through the amplification of mucosal immunity, meaning the virus would be blocked at the point of entry. Mucous membranes can produce B cells, which, in turn, produce immunoglobin A (IgA) antibodies. Those antibodies work across mucosal surfaces found throughout the body, including the nose, lungs, and stomach.
Multiple pharmaceutical developers across the globe have been attempting to develop nasal spray vaccines. Some have shown promise, while others, such as Maryland-based Altimmune’s AdCovid, proved unsuccessful in the clinic. Bharat Biotech is advancing BBV154, a Phase II intranasally-delivered vaccine being developed in India. Codagenix and pHOXBIO Ltd, both advanced clinical studies of intranasal formulations of a COVID vaccine this past fall.
Multiple university programs are also diving into this kind of approach. In February, Australian scientists began assessing a nasal formulation of mRNA-based vaccines, similar to those injectable versions developed by Pfizer and Moderna. Other scientists in Australia are looking at intranasal dosing of interferon. The spray is being assessed in cancer patients to provide them with additional protection against the virus.
Researchers at Stanford University are studying an intranasal spray that uses gold nanoparticles. These nanoparticles contain what was described as “bits of harmless, virus-mimicking DNA” that harness antibodies and other immune cells in order to fight and neutralize the threat of the SARS-CoV-2 virus. The researchers noted the nanoparticles act as a physical barrier against the infection in a Stanford University news agency report.
According to the report, the gold nanoparticles are expected to limit the number of virus particles entering the respiratory system through the nasal passages. This would limit infection in the individual and potentially reduce their ability to transmit the virus to other people.