Clinical Evaluation of an Atopic Skin Product Containing Picea Abies Resin Extract

Clinical-Instrumental Evaluation of the Efficacy of Two Cosmetic Products in Comparison: Placebo Controlled Study

This study evaluates the repairing efficacy of a cosmetic cream containing Picea abies extract compared to a placebo (cream without extract) and a benchmark product. The trial involves 60 healthy subjects (aged 18-60) with atopy-prone and sensitive skin.

Over a 21-day period, the primary objective is to measure improvements in skin barrier function via transepidermal water loss (TEWL) and skin moisturization. A dermatologist will also assess soothing effects by evaluating skin dryness, redness, and itching sensations. Secondary objectives include measuring skin inflammation markers (TNFα, TSLP, and TARC) and subject-perceived efficacy through self-assessment questionnaires.

This is a multi-site, randomized, placebo-controlled, and benchmark-controlled clinical trial designed to evaluate the repairing and soothing efficacy of a cosmetic cream containing Picea abies extract. The study is conducted on 60 healthy male and female subjects (66 enrolled to account for a 10% dropout rate) aged 18 to 60 years who exhibit atopy-prone and sensitive skin.

Subjects are randomized into three parallel groups (N=20 per group):

Test Product: Atopic cream with Picea abies extract.

Placebo: Atopic cream without Picea abies extract.

Benchmark: A commercially available reference cream.

The intervention consists of applying the assigned product twice daily to clean, dry skin on the face and body for a duration of 21 days.

Clinical and instrumental evaluations are performed at baseline (T0) and after 21 days (T21). Instrumental assessments include the measurement of Transepidermal Water Loss (TEWL) and skin moisturization levels. Clinical evaluations are conducted by a dermatologist to assess physical signs (dryness, desquamation, redness) and functional signs (stinging, itching, burning, and tightness). Additionally, skin inflammation markers (TNFα, TSLP, and TARC) are dosed to evaluate the biological effect on skin barrier inflammation. Subjective efficacy is captured through a standardized self-assessment questionnaire.

Inclusion Criteria:

• Healthy male and female subjects aged 18 to 60 years.
• Caucasian ethnicity.
• Subjects with atopy-prone skin on cheekbones and forearms, characterized by sensitive/reactive skin, redness, or itching.
• Transepidermal water loss (TEWL) thresholds at screening: Cheekbones ≥ 20 g/m^2/h and Forearms ≥10 g/m^2/h.
• Stable pharmacological therapy for at least one month without planned changes.
• Subjects aware of study procedures and having signed an informed consent form.

Exclusion Criteria:

• Acute or chronic diseases liable to interfere with study data or subject safety.
• Participation in other clinical trials or insufficient washout period (14 days).
• Known hypersensitivity or allergy to any ingredients in the test products.
• Use of pharmacological treatments considered incompatible with the study requirements.
• Presence of skin diseases that could interfere with instrumental measurements.
• Pregnant or breastfeeding women, or women of childbearing potential unwilling to use precautions to avoid pregnancy.