Evaluation of a novel emollient plus providing protection against allergens and pollution, and relieving pruritus in atopic dermatitis

Atopic dermatitis (AD) affects millions of patients worldwide and significantly impairs quality of life. AD is characterized by skin barrier dysfunction, leading to the release of keratinocyte- and mast cell–derived alarmins, including thymic stromal lymphopoietin (TSLP), which directly both activates sensory neurons involved in pruritus¹ and promotes type 2 inflammation².

Barrier disruption enhances the penetration of allergens, pathogens, and irritants and contributes to exaggerated immune responses. Moreover, AD patients frequently exhibit IgE reactivity to environmental allergens, microbes, or food proteins, which can trigger or worsen disease flares^3,4, sustaining a pathogenic cycle of chronic inflammation and skin discomfort.

Therefore, this study evaluated the protective effect against allergens and pollution of a balm emollient plus (AD balm) formulated with a biomimetic lipid phase, the ability of an incorporated active ingredient to modulate TSLP production, and the AD balm clinical efficacy in reducing pruritus.

1. Wilson SR, Thé L, Batia LM, Beattie K, Katibah GE, McClain SP, Pellegrino M, Estandian DM, Bautista DM. The epithelial cell-derived atopic dermatitis cytokine TSLP activates neurons to induce itch. Cell. 2013 Oct 10;155(2):285-95. 
2. Misery L. La TSLP, clé du prurit dans la dermatite atopique (TSLP, the key of pruritus in atopic dermatitis). Med Sci (Paris). 2014;30(2):142-144.
3. Langan SM, Irvine AD, Weidinger S. Atopic dermatitis. Lancet. 2020 Aug 1;396(10247):345-360. 
4. Werfel T, Allam JP, Biedermann T, Eyerich K, Gilles S, Guttman-Yassky E, Hoetzenecker W, Knol E, Simon HU, Wollenberg A, Bieber T, Lauener R, Schmid-Grendelmeier P, Traidl-Hoffmann C, Akdis CA. Cellular and molecular immunologic mechanisms in patients with atopic dermatitis. J Allergy Clin Immunol. 2016 Aug;138(2):336-49.

The effect of the active ingredient on TSLP production was evaluated using an atopic-like in vitro model of human primary keratinocytes stimulated with IL‑4, TNF‑α and poly(I:C). TSLP secretion was quantified by ELISA. Dexamethasone served as a positive control.

The physical protective effect of the AD balm against allergens was assessed using four different allergens—house dust mite (Der p1), cat (Fel d1), mold (Alt a1) and peanut (Ara h2)—labelled with a fluorophore. Human shaved scalp explants were topically pre-treated with the AD balm before allergen application. Allergen skin penetration was evaluated in follicular infundibulum areas by image analysis.

Protection against pollution was evaluated on the forearms of 10 healthy subjects. Water or the AD balm was applied, followed by exposure to 1 μm carbon particles. After washing, residual particles were quantified by colorimetric analysis (L*).

Open-label clinical efficacy study of the AD balm on pruritus was evaluated in 30 adults with chronic or chronically relapsing atopic dermatitis and significant itching (Numerical Rating Scale ≥4/10). After a 3‑day washout period, the balm was applied to the forearm. Pruritus soothing was assessed immediately (1 second) by satisfaction, and after 1 minute and 1 hour using the NRS. Soothing efficacy was also self‑assessed after 10 hours and after 7 days of twice‑daily application to the face and body using a questionnaire.

The active ingredient significantly inhibited TSLP secretion by human keratinocytes (−73%) compared with the atopic-like control, with an efficacy comparable to dexamethasone.

On scalp explants, the AD balm provided a significant physical barrier against allergens, reducing cutaneous accumulation by −71% for house dust mite, −92% for cat, −81% for mold and −85% for peanut allergens. On healthy subjects, protection against pollution was also observed, with a 80% reduction in residual carbon particles versus water.

On atopic subjects, the AD balm demonstrated pruritus soothing from 1 second, reported by 100% of subjects. Itch intensity was significantly reduced by 55% after 1 minute and 82% after 1 hour. The effect persisted throughout the day, with 96% of subjects still reporting pruritus relief after 10 hours. After 7 days of twice-daily use, more than 95% of subjects reported relief discomfort.

This novel AD emollient balm provides rapid and long-lasting relief of pruritus and skin discomfort in patients with atopic dermatitis. These clinical benefits may be partly explained by the inhibition of keratinocyte-derived TSLP by the active ingredient, and by the biomimetic lipid-replenishing phase. By forming a physical barrier that limits allergen and pollution penetration, the balm may contribute to sustained skin protection and help reduce the risk of flare-ups. Overall, this AD balm represents an effective supportive care to improve skin comfort and quality of life in patients with atopic dermatitis.