An experimental nose spray developed in Finland could protect people from COVID-19 infection for up to 8 hours. Researchers from the University of Helsinki developed a novel treatment that successfully blocked infection from the virus during animal laboratory studies. The mice that were used in the study also were less likely to have upper respiratory distress after contact with the virus when the spray was administered.

“This technology is cheap and highly manufacturable, and the inhibitor works well against all variants,” said one of the study’s authors, Kalle Saksela, according to the New York Post. The spray recognizes and binds to the spike protein of the coronavirus temporarily inhibiting its function. It was originally developed for people with compromised immune systems and those at elevated risk for severe disease from COVID-19. The nasal spray contains an antibody-like protein and researchers say a small dose stopped cells from being infected even from the omicron variant of SARS-CoV-2, the virus responsible for COVID-19.

The spray utilizes an innovative technology called TriSb92, a molecule developed by the researchers that protects against coronavirus infection for at least 8 hours, even in high-risk situations. Unlike vaccines, TriSb92 starts working immediately after it has been administered. It targets a specific site on the coronavirus spike protein that is common to all variants, explained Anna Makela, the first author of the study.

“In other words, we can fairly confidently assume that future variants of SARS-CoV-2 and perhaps even entirely new coronaviruses that may threaten to cause pandemics are susceptible to it,” she said. The product will potentially provide a “biological mask” to protect against coronavirus infections when sprayed on the mucous membranes.

The University of Helsinki study has not been peer reviewed, and the intranasal inhibiting spray needs to be tested on humans, say experts, so more research is needed before it becomes an approved treatment for COVID-19.

Saksela said that the spray was not developed to replace vaccines or other treatments for COVID-19, according to the Post.

“Its prophylactic use is meant to protect from SARS-CoV-2 infection,” she said. “However, it is not a vaccine, nor meant to be an alternative for vaccines, but rather to complement vaccination for providing additional protection.”

However, given the current situation where the omicron variant appears able to evade vaccine protection, the nasal spray may be a crucial treatment addition for those who are immunocompromised or at higher risk for severe disease.

“Individuals whose immune system does not respond strongly enough to vaccines spring to mind in particular,” Saksela said. “Having said that, we know that new variants, especially omicron, are capable of circumventing even effective vaccine responses worryingly well. Taken before any kind of social interaction, TriSb92 could be useful to people whose vaccine protection is insufficient for one reason or another. Depending on the epidemic situation, it could also benefit fully vaccinated individuals before any situation with a high-risk exposure.”