Efficacy and safety of a drug-free, barrier-forming nasal spray for allergic rhinitis: randomized, open-label, crossover noninferiority trial

Abstract

BackgroundSymptoms of allergic rhinitis can be reduced by nonpharmacological nasal sprays that create a barrier between allergens and the nasal mucosa. A new nasal spray (AM-301) containing the clay mineral bentonite was tested for its ability to reduce symptoms to grass pollen.MethodsThis open label, crossover, noninferiority trial compared the efficacy and safety of AM-301 to that of hydroxypropyl methylcellulose (HPMC; Nasaleze Allergy Blocker), an established barrier method. Adults with seasonal allergic rhinitis were exposed to Dactylis glomerata pollen, in the Fraunhofer Allergen Challenge Chamber, first without protection and then protected by HPMC or AM-301 (7 days apart). Efficacy was assessed from total nasal symptom score (TNSS), nasal secretion weight, and subjective rating. The primary endpoint was the difference, between AM-301 and HPMC, in least square mean change in TNSS over a 4-hour exposure to allergen.ResultsThe study enrolled 36 persons, and 35 completed all study visits. The mean TNSS was 5.91 during unprotected exposure, 5.20 during protection with HPMC, and 4.82 during protection with AM-301. The difference in least square means between the two treatments was -0.39 (95% CI, -0.89 to 0.10), establishing the noninferiority of AM-301. No difference in mean weight of nasal secretions was observed between the treatments. Efficacy was rated as good or very good for AM-301 by 31% and for HPMC by 14% of subjects. 16 subjects reported adverse events with a relationship to AM-301 or HPMC; most adverse events were mild and none was serious.ConclusionsAM-301 demonstrated noninferiority towards HPMC in the primary endpoint and was perceived better in subjective secondary endpoints. Both barrier-forming products had a persisting protective effect over 4 hours and were safe.Trial registrationGerman Clinical Trial Register (DRKS00024356). EUDAMED (CIV-20-10-034870).

Efficacy and Safety of a Drug-Free, Barrier-Forming Nasal Spray for Allergic Rhinitis: Randomized, Open-Label, Crossover Noninferiority Trial

“…The medical devices used in the study are commercially available in some countries. A preprint version of this article is available on medRxiv [32].…”

Drug-Free Nasal Spray as a Barrier against SARS-CoV-2 and Its Delta Variant: In Vitro Study of Safety and Efficacy in Human Nasal Airway Epithelia

“…However, there was no difference between AM-301 and its matrix, suggesting that bentonite is not responsible for this effect, which may rather be due to the viscosity of the formulation. Importantly, safety and tolerability of AM-301 were further confirmed in a clinical investigation with 36 allergic rhinitis patients, where AM-301 was well tolerated and was considered safe for human use [ 33 ].…”

“…AM-301 was applied once every 24 h, whereas in patients, 2–3 administrations per day would be likely. Indeed, clinical data from an allergen exposure chamber study showed that AM-301 well tolerated and provided a protective effect lasting more than 3 h [ 33 ]. The encouraging results of these studies in which the effect of AM-301 was shown for both viruses and allergens imply a mechanism of action likely to be applicable to diverse airborne particles and call for further investigations in vivo and in humans, to further evaluate AM-301 as a medical device with a broad spectrum of action against as other viruses, allergens, and possibly pollutants.…”