FDA Clears Barrier-Forming Nasal Spray for Allergic Rhinitis

Bentrio is a drug-free, preservative-free, OTC nasal spray for protection against airborne allergens.

The Food and Drug Administration (FDA) has granted 510(k) clearance to Bentrio nasal spray (“Bentrio Allergy Blocker”) to treat allergic rhinitis by promoting alleviation of mild allergic symptoms (eg, mild nasal irritation including itchy, runny, or congested nasal passages) triggered by the inhalation of various airborne allergens including indoor and outdoor environmental pollens, house dust, animal hair and dust mites.

Bentrio is a drug-free, preservative-free, over-the-counter (OTC) nasal spray that contains the clay mineral bentonite. Upon application into the nose, a thin protective gel layer is formed on the nasal mucosa to prevent contact of allergens with cells. The product works by binding these particles within the nasal cavity, which then helps with their discharge via natural cleaning of the nasal mucosa.

The safety and efficacy of Bentrio was compared with hydroxypropyl methylcellulose, another barrier forming product, in an open-label, crossover, noninferiority trial that included 36 participants with seasonal allergic rhinitis. The primary endpoint of the study was the difference in total nasal symptom score over a 4-hour exposure to Dactylis glomerata pollen. Results showed that both barrier-forming products conferred a protective effect over the 4 hour period; Bentrio was found to be noninferior to the hydroxypropyl methylcellulose product.

“Thanks to its triple mode of action, which does not require any drug ingredient for protecting against airborne allergens, and its preservative-free formulation, we believe that Bentrio is well positioned to help address unmet needs among the more than 20 million allergic rhinitis sufferers in the US,” said Thomas Meyer, Altamira Therapeutics’ founder, Chairman and CEO.

The product is expected to be available in the US later in the third quarter 2022.


  1. Altamira Therapeutics receives FDA 510(k) clearance for Bentrio to treat allergic rhinitis. News release. Altamira Therapeutics Ltd. Accessed June 27, 2022. https://feeds.issuerdirect.com/news-release.html?newsid=7697067252927652
  2. Nehrig J, Grosse N, et al. Efficacy and safety of a drug-free, barrier-forming nasal spray for allergic rhinitis: randomized, open-label, crossover noninferiority trial. Published online August 6, 2021. https://www.medrxiv.org/content/10.1101/2021.08.02.21261374v1