FDA approves 1st at-home nasal spray flu vaccine, paving the way for other medicines

The FDA has approved a new flu vaccine nasal spray for at-home use. While this self-administered version won't be available for this year's flu season, interest in nasal spray products is growing.

A simple spray seems much more inviting than a needle. Intranasal devices deliver medication for people with allergies, migraines, depression and opioid overdoses -- and now vaccines. FluMist had been approved for use since 2003, but fell out of favor in 2016 when regulators said it was less effective than the injectable ones.

Now, a newly CDC-recommended, self-administered version of FluMist that meets efficacy standards is FDA-approved for next flu season.

The FDA approved FluMist for self-administration in adults 18 to 49. It can be administered to those 2 to 17 years old by a caregiver. AstraZeneca plans to sell it online directly to consumers.

Related story: CDC recommends nasal flu spray for children

Researchers expect other vaccines will follow. Some are already investigating nasal sprays for Alzheimer's disease and abnormal heart rhythms.

"Mucosal immunization gives you superior immunity in the airways, which is of a special utility for respiratory diseases, like COVID," said Dr. David T. Curiel, a radiation oncologist with Washington University School of Medicine.

Curiel said vaccines in nasal form target the airway, where a respiratory virus enters the body. Traditional needle immunizations produce antibodies in the blood, but not so much in the lungs.

"Airway vaccination, nasal vaccination, augments antibodies in the nose and airways -- and that's a better defense," Curiel explained.

Instead of an epi-pen, people who suffer from severe allergic reactions like anaphylaxis can talk to their doctors about a nasal spray version called Neffy. The FDA approved Neffy in August and is available now.

"We know enough about the biology of the nose," Curiel said. "We know enough about the immunology of the nose."