Tolerance and Efficacy Open-label Study With RV4421B, in Various Populations With Atopic Dermatitis for 12 Weeks

Inclusion criteria: * Male or female, with any phototype according to Fitzpatrick classification aged: * Group 1 (infants group): from 3 months to 23 months old included * Group 2 (children group): from 24 months to 12 years old included * Group 3 (teenagers \& adults group): from 13 years old * Subject with a diagnosis of atopic dermatitis according to the U.K. Working Party's Diagnostic Criteria for Atopic Dermatitis (Williams HC, Burney PG, et al.). * Subject with studied areas (lesions and prevailing xerotic areas) limited up to 30% of the body surface area * Subject with mild to moderate Atopic Dermatitis Criteria related to treatments and/or products: • Topical corticosteroids treatments (following international treatment guidelines for each age sub-group and including investigator agreement) applied on AD lesions areas since 1 to 5 days before the inclusion and ongoing at the time of inclusion. \* \*The investigator will be authorized to adjust the treatment during the study. Exclusion criteria: Criteria related to the skin condition or the disease: * Infant with Atopic Dermatitis lesions or prevailing xerotic areas located on the diaper (groups 1 \& 2) * Subject with history of allergy or intolerance to any of the study product(s) ingredients or material used for the research * Subject having any other dermatologic condition than Atopic Dermatitis, or characteristics (like tattoo…) on the studied areas liable to interfere with the study assessments * Subject ha…