This exploratory study aims to evaluate the impact of a cosmetic product (Lactibiane Topic AD) vs placebo on skin flora and skin reinforcement barrier in mild to moderate atopic dermatitis using biometrological, biological and clinical parameters.

Inclusion Criteria:

• Subject diagnosed with mild to moderate AD defined as SCORAD≤40 (Eichenfield et al. JAAD 2014).
• Subject with at least two symmetric AD lesions with comparable severity: Located either on upper extremities (left and right arms except hands) or lower extremities (left and right legs except feet), With an erythema ≥ 1 (mild to severe intensity), With a lesional area score ≥ 4 on both lesions with an authorized delta of two points between the two lesions, With a sufficient extent to allow all the investigations.
• Subject with I, II, III or IV skin phototype (according to Fitzpatrick's scale).
• For woman of childbearing potential (defined as all women physiologically capable of becoming pregnant): Negative urine pregnancy test at inclusion visit. Use of a highly effective method of birth control* during the study. * A highly effective method of birth control is defined as one which results in a low failure rate (less than 1%) when used consistently and correctly, such as implants, combined oral contraceptives, intrauterine device, double barrier methods (e.g. condom with spermicide), sexual abstinence or vasectomized partner.
• Subject with health insurance coverage according to local regulation.
• Subject having given his written informed consent.

Exclusion Criteria:

• Subject having a known hypersensitivity, allergy or contraindication to any ingredients contained within the investigational product or placebo.
• Subject having exposed his skin to natural or artificial UV within 8 weeks prior to the inclusion visit or intending to expose his skin during the study.
• Subject having performed phototherapy within 8 weeks prior to the inclusion visit or intending to perform phototherapy during the study.
• Subject having performed another physical treatment (e.g radiotherapy…) on the investigational areas within 6 months prior to the inclusion visit or intending to perform it during the study.
• Subject treated with systemic non-steroidal anti-inflammatory drugs (≥3 days) within 1 week before the inclusion visit.
• Subject treated with biological immunosuppressive drugs within 12 weeks prior to the inclusion visit or intending to be treated with it during the study.
• Subject treated with non-biological immunosuppressive drugs within 4 weeks prior to the inclusion visit or intending to be treated with it during the study.
• Subject treated with systemic corticoids within 1 week prior to the inclusion visit or planed during the study.
• Subject treated with systemic antibiotics within 7 days prior to the inclusion visit or planed during the study.
• Subject having applied topical immunomodulators, non-steroidal anti-inflammatory, corticoids or antihistamines on investigational limbs within 1 weeks prior to the inclusion visit.
• Subject having applied topical antibiotics or disinfectants on investigational limbs within 2 weeks prior to the inclusion visit.
• Subject having applied any other topical and/or care product after the last grooming prior to the inclusion visit.
• Subject having applied water or care product (except hands cleaning) within 12 hours prior to the inclusion visit.
• Subject having started, modified or stopped any other treatment/product within 4 weeks prior to the inclusion visit or intending to do so during the study that according to the investigator's judgment, could interfere with study results.
• Subject having significant medical condition that according to the investigator's judgment, deems inappropriate for study participation (e.g present or past malignancy, present or past skin condition…).
• Subject having significant dermatological condition or sign (e.g disease, scare, abundant hairiness, tanning mark…) that according to the investigator's judgment, could limit the observations or/and interfere with the interpretations.
• Subject taking part or having participated in another clinical study within 2 weeks prior to the inclusion visit.
• Subject under legal guardianship or incapacitation.
• Subject linguistically or psychologically unable of signing informed consent form and unable to comply with the protocol requirements according to the investigator's judgment.