Drug-free nasal spray could protect against COVID and flu

According to Brigham and Women's Hospital, a new study has found that a new drug-free nasal spray may protect against respiratory infections such as COVID and flu.

“The COVID pandemic has shown us what respiratory pathogens can do to humanity in a very short period of time,” said Jeffrey Karp, co-senior author of the study and chair of anesthesiology at Brigham and Women's Hospital. “That threat has not gone away.”

“We need new, additional ways to protect ourselves and contain the transmission of the disease,” Karp added.

The preclinical studies show that the nasal spray, called Pathogen Capture and Neutralizing Spray, or PCANS, can block respiratory infections, the hospital said. The study was conducted at Brigham and Women's Hospital and published in the journal Advanced Materials.

The hospital said protective measures such as vaccinations and masks are useful but not perfect. “Infections with influenza and COVID-19 cause thousands of deaths and hundreds of thousands of cases of serious illness each year,” the hospital said.

Most viruses enter people through the nose, the press release says. They spread when infected people exhale tiny droplets of fluid. Healthy people breathe in these droplets, the hospital says, thereby infecting “cells that line the nasal passages.”

Researchers developed the nasal spray to stop infection in the nose, using ingredients that the FDA has approved or found safe for use in other nasal sprays. The spray was tested in a lab using replica human noses and mice, not on people.

“We developed a drug-free formulation with these compounds to block germs in three ways – PCANS forms a gel-like matrix that captures respiratory droplets, immobilizes the germs and effectively neutralizes them, preventing infection,” said co-senior author Nitin Joshi, assistant professor of anesthesiology.

When sprayed into a simulated nasal cavity, the press release said, PCANS “captured twice as many droplets as mucus alone.” In mice treated with the spray, it was shown to block the flu virus at 25 times the lethal dose, giving them “complete protection,” the researchers said.