COVID-19 Nasal Vaccine Candidate Shows Promise of Development

Investigators said that NanoSTING, can be shipped and stored without the need for freezing for up to 11 months.

An intranasal subunit vaccine, NanoSTING, against severe acute respiratory syndrome coronavirus 2 is being developed, according to a report in iScience.

“Mucosal vaccination can stimulate both systemic and mucosal immunity and has the advantage of being a non-invasive procedure suitable for immunization of large populations,” Narvin Varadarajan, professor of chemical biomolecular engineering at the University of Houston, said in a statement. “However, mucosal vaccination has been hampered by the lack of efficient delivery of the antigen and the need for appropriate adjuvants that can stimulate a robust immune response without toxicity.”

Investigators of the nasal vaccine intended for it to be the first barrier against the virus and promote the body’s immune response.

The investigators encapsulated the agonist of the stimulator of interferon genes (STING) within liposomal particles to create NanoSTING.

A limitation of intermuscular vaccines is that they do not elicit mucosal immunity, which is how nasal vaccines differ, the investigators said.

Investigators said their focus is to distribute the vaccines worldwide and promote accessibility of the vaccine for countries that are still unvaccinated.

“Equitable distribution requires vaccines that are stable and that can be shipped easily. As we have shown, each of our components, the protein (lyophilized) and the adjuvant (NanoSTING) are stable for over 11 months and can be stored and shipped without the need for freezing,” Varadarajan said.

NanoSTING has not been approved for use but is a candidate for the first nasal COVID-19 vaccine.