Adapalene gel 0.1% is better tolerated than tretinoin gel 0.025% among healthy volunteers of various ethnic origins

• Published in: The Journal of dermatological treatment Vol. 20; no. 5; pp. 282 - 288
• Main Authors: Leok Goh, Chee, Tang, Mark B.Y., Briantais, Philippe, Kaoukhov, Alexandre, Soto, Pascale
• Format: Journal Article
• Language: English
• Published: Oslo Informa UK Ltd 2009; Taylor & Francis
• Subjects: Adapalene; Administration, Cutaneous; Adolescent; Adult; Aged; Biological and medical sciences; Dermatologic Agents - administration & dosage; Dermatologic Agents - adverse effects; Dermatology; ethnic groups; Gels; Humans; irritation potential; Medical sciences; Middle Aged; Naphthalenes - administration & dosage; Naphthalenes - adverse effects; Pharmacology. Drug treatments; Single-Blind Method; Skin Diseases - chemically induced; Skin Diseases - ethnology; Skin Diseases - pathology; Skin involvement in other diseases. Miscellaneous. General aspects; Skin Irritancy Tests; Skin, nail, hair, dermoskeleton; tretinoin; Tretinoin - administration & dosage; Tretinoin - adverse effects; Young Adult; Antineoplastic agent; Human; Skin disease; Healthy subject; Adapalene; Toxicity; Treatment efficiency; irritation potential; Retinoid; Ethnic group; Colloidal gel; ethnic groups; Secondary effect; Antiacneic agent; Comparative study; Irritation; Tretinoin
• ISSN: 0954-6634; 1471-1753
• DOI: 10.1080/09546630902763164

Background: The efficacious acne treatment adapalene gel 0.1% is significantly less irritating than tretinoin of various concentrations and formulations, according to several clinical studies conducted predominantly in Caucasian patients. Objectives: To confirm the lower irritation potential of adapalene gel 0.1% compared to tretinoin gel 0.025% among volunteers of various ethnic origins and to explore the difference in the irritant susceptibility among ethnic groups. Methods: The study was a single-centre, randomized, investigator-masked and intra-individual comparison. Healthy volunteers applied adapalene and tretinoin daily to the face for 21 days and to the forearms for 4 days, and were then evaluated for the level of irritation. Results: The irritation potential of adapalene gel 0.1% was significantly lower than that of tretinoin gel 0.025% in all tolerability assessments, irrespective of the volunteers' ethnic origins. The between-treatment differences were similar among various ethnic groups. Statistically significant but small inter-ethnicity differences were observed in the evaluation of facial signs, with Caucasians being less susceptible than Chinese, Asian Indians and Malays. Conclusion: Adapalene gel 0.1% was significantly better tolerated than tretinoin gel 0.025% among various ethnic groups. The patients' ethnic origins had no impact on the difference between adapalene and tretinoin treatments in terms of tolerability.