Thin film barrier more effective in seasonal allergic rhinitis than saline nasal spray

Key takeaways:

• Patients used AM-301 or saline nasal spray three times a day for 2 weeks.
• The AM-301 group had greater improvements in Total Nasal Symptom Scores.
• Safety and tolerability profiles were similar.

AM-301 nasal spray was significantly more effective than saline nasal spray in relieving symptoms and improving health-related quality of life among patients with seasonal allergic rhinitis, according to a study published by Allergy.

Both treatments had similar safety and tolerability profiles, Sven Becker, Priv-Doz Dr med MHBA, deputy director, department of otorhinolaryngology, head and neck surgery, University Medical Center of Eberhard-Karls University Tübingen, and colleagues wrote.

Whereas saline or seawater nasal sprays cleanse and clear aeroallergens from the nasal cavity, AM-301 (Bentrio, Altamira Medica AG) forms a thin film barrier over nasal mucosa to prevent contact with allergens as well as trap them and facilitate their discharge.

Becker and colleagues conducted a randomized, clinical controlled trial to compare the two nasal sprays. Their cohort included 100 adults (53.1% women) aged 18 to 75 years (mean age = 41.1 years) with a history of seasonal allergic rhinitis of 2 or more years and a positive skin prick test or specific IgE at baseline or within the 12 months before enrollment. The study also included an “investigator group.”

The mean baseline daily reflective Total Nasal Symptom Score (rTNSS) was 6.8 points, and the mean baseline Rhinoconjunctivitis Quality of Life Questionnaire (RQLQ) score was 2.9 points. Also, 59% had moderate or severe symptom levels.

Fifty patients used AM-301 and 50 used saline nasal spray (FESS, Care Pharmaceuticals Pty Ltd) from September 2021 to April 2022 and from September 2022 to January 2023, which were pollen seasons in Australia.

Participants spent an average of 2.7 hours outdoors each day, and daily pollen counts ranged from less than 20 grains/m³ to more than 100 grains/m³ during the treatment period.

Mean rTNSS scores fell by an average of 1.8 points for the AM-301 group and by 0.77 points for the saline spray group (P = .0111). The researchers also classified the improvement with AM-301 treatment beginning at day 1 as consistently larger.

Specific reductions at day 14 included 2.3 points for the AM-301 group and 0.61 points for the saline spray group.

Additionally, mean rTNSS over the treatment period included 5.01 for the AM-301 group and 6.07 for the saline spray group, which the researchers called a statistically significant difference. In the ANCOVA model, this least square (LS) means difference was –1.1 points (95% CI, –1.959 to –0.241; P = .013).

Within the treatment groups, rTNSS severity and improvement from baseline for both pollen seasons were comparable.

AM-301 had superior treatment effects across all secondary efficacy endpoints as well, Becker and colleagues wrote. Average LS mean differences for individual rTNSS nasal symptoms ranged from –0.24 to –0.32 across the treatment period, with P values indicating statistical significance ranging from .012 to .046.

Instantaneous Total Nasal Symptom Score (iTNSS) fell by –1.7 points for the AM-301 group and –1.1 points for the nasal spray group from baseline levels, which the researchers categorized as lower, through the treatment period. The ANCOVA model yielded a –0.815-point difference in mean iTNSS between the groups (95% CI, –1.589 to –0.042; P = .039), favoring AM-301.

Averaged over the treatment period, the difference in LS means for nasal itching was –0.27 points (P = .016). Differences in LS means for the other three iTNSS items ranged from –0.17 to –0.19 points.

Improvements in RQLQ from baseline included 1.2 points for the AM-301 group and 0.4 points for the saline spray group (P < .01). In the ANCOVA model, there was a –0.7-point difference in LS means (95% CI, –1.093 to –0.305; P < .001) for the day 8 (1.68 points) and day 15 (2.38 points) mean RQLQ levels.

In all individual domains, the AM-301 group had larger improvements than the saline spray group. LS means differences ranged from –0.6 to –0.8, and P values ranged from .024 to .001).

In Global Impression of Efficacy evaluations, the AM-301 group also had greater patient (P < .001) and investigator (P < .001) than the saline spray group, the researchers said, with differences that were statistically significant.

Among the AM-301 group, 34.4% said the treatment’s efficacy was good, 31.9% said it was very good, and 8.5% said it was poor. Among the saline spray group, 22.4% said the treatment’s efficacy was good 6.1% said it was very good, and 46.9% said it was poor. The investigators’ ratings were similar.

The researchers further wrote that both groups tolerated treatment well; there were no statistically significant differences in the Global Impression of Tolerability patient and investigator ratings.

Also, 31.9% of the AM-301 group and 30.6% of the saline spray group rated tolerability as “good;” 44.7% of the AM-301 group and 55.1% of the saline spray group rated it as “very good;” and 6.4% of the AM-301 group and 10.2% of the saline spray group rated it as “poor.”

The investigators rated saline spray as somewhat more favorable than AM-301, the researchers said, but ratings overall otherwise were similar.

Additionally, 42.9% of the AM-301 group and 32.7% of the saline spray group experienced treatment-emergent adverse events, which the researchers called transitory and mostly mild. None were considered severe.

The most common treatment-emergent adverse events included headache, affecting five patients in the AM-301 group and six in the saline spray group; oropharyngeal pain, affecting five in the AM-301 group and one in the saline spray group; epistaxis, affecting three in the saline spray group; throat irritation, affecting two in the AM-301 group; and migraine and tension headache, affecting two in the AM-301 group.

Percentages of patients who required relief medication included 20.8% in the AM-301 group and 31.9% in the saline spray group. Also, 59.2% of the AM-301 group and 30.6% of the saline spray group experienced symptom-free days during treatment.

Based on these findings, Becker and colleagues concluded that AM-301 consistently yielded more pronounced and statistically significant improvements in TNSS and RQLQ than nasal spray, with more rapid and longer lasting effects.

These findings also indicate that AM-301 may be considered as a safe and tolerable alternative to medicated treatment or as a complement to it, particularly for more severe seasonal allergic rhinitis conditions, the researchers wrote.