Study Shows Nasal Spray Protects Against Any Flu Strain

According to preliminary human trials, an antibody nasal spray shows promise for protecting against flu, and it may be useful for combating future flu pandemics because it seems to neutralize any kind of influenza virus, including those that are transferred from non-human animals.

Initially developed by Johnson & Johnson, the antibody (called CR9114) can neutralize any flu strain by recognizing and binding to a part of the virus that always stays the same, regardless of how other parts of it are changing. However, when it was initially injected into animals’ bloodstreams, it failed to provide robust protection against flu because only a small proportion reached the nose, the main point of entry for influenza viruses. But, in 2022, when Leyden Labs licensed CR9114 and developed a formulation that could be sprayed up the nose, the company has shown spraying CR9114 up the noses of mice and macaques stops them from getting sick when they are exposed to various strains of influenza A and B, including one collected from a bad flu season in 1933.

Preliminary tests were also conducted in 143 people aged 18 to 55 and found that administering the spray twice a day maintained steady levels of the antibody inside participants’ noses and didn’t cause any major side effects. Samples of their nasal mucus collected afterward also neutralized a range of influenza strains, including a bird flu strain that crossed into people in China in 2013.

According to the researchers, the next step will be to directly expose people who have used the spray to a range of influenza viruses to confirm it actually stops them from getting sick.