the invisible process of normal skin desquamation via individual separation of corneocytes. When there is diminished SC water content below a physiologic level, these hydrolytic enzymes function sub-optimally, leading to incomplete separation and clumping of individual corneocytes, which can be perceived visibly as scaling.2
Topical skincare products, including creams, lotions, and ointments have been widely used to protect and maintain skin barrier structure and function. A major emphasis of optimized moisturizer formulations has been to incorporate ingredients that reduce TEWL (occlusives, NMFs) and to replenish and/or support functional components (NMFs, ceramides antioxidants, others).4,13 Due to their established major importance in skin barrier functions, and their impairment and/or quantitative decrease in several environmental or disease-associated scenarios, ceramides are frequently included ingredients in many topical skin moisturizers; many formulations also contain NMFs to further enhance the maintenance of skin barrier function by including compounds found in the innate epidermal barrier.4,13,14
In the present study, we describe the head-to-head clinical comparison of 2 ceramide plus NMF-enriched formulations (cream and lotion) and a ceramide-based formulation (cream) on skin hydration in 2 double-blinded comparative studies after 10 days of daily bilateral application followed by 5 days of no moisturizer use for regression analysis.
Topical skincare products, including creams, lotions, and ointments have been widely used to protect and maintain skin barrier structure and function. A major emphasis of optimized moisturizer formulations has been to incorporate ingredients that reduce TEWL (occlusives, NMFs) and to replenish and/or support functional components (NMFs, ceramides antioxidants, others).4,13 Due to their established major importance in skin barrier functions, and their impairment and/or quantitative decrease in several environmental or disease-associated scenarios, ceramides are frequently included ingredients in many topical skin moisturizers; many formulations also contain NMFs to further enhance the maintenance of skin barrier function by including compounds found in the innate epidermal barrier.4,13,14
In the present study, we describe the head-to-head clinical comparison of 2 ceramide plus NMF-enriched formulations (cream and lotion) and a ceramide-based formulation (cream) on skin hydration in 2 double-blinded comparative studies after 10 days of daily bilateral application followed by 5 days of no moisturizer use for regression analysis.
MATERIALS AND METHODS
Test Products
Study 1: Moisturizer A, Ceramide plus natural moisturizing factor-enriched cream (Eucerin Advanced Repair Cream, Beiersdorf Inc.); Moisturizer B, Ceramide-based cream (CeraVe Moisturizing Cream, L’Oreal Group).
Study 2: Moisturizer C, Ceramide plus natural moisturizing factor-enriched lotion (Eucerin Advanced Repair Lotion, Beiersdorf Inc.); Moisturizer B, Ceramide-based cream (CeraVe Moisturizing Cream, L’Oreal Group).
Institutional Review Board
Prior to participant enrollment for the study, the protocol and informed consent form (ICF) for this study were reviewed and approved by IntegReview Institutional Review Board (IRB) on September 26, 2016. IntegReview IRB, located in Austin, Texas, is a duly constituted IRB under Title 21 Code of Federal Regulations (CFR) Parts 50 and 56.
Informed Consent
Written informed consent conforming to 21 Code of Federal Regulations (CFR) 50.25 was obtained from each adult participant (at least 18 years old) or the parent/guardian of each minor H.E. Baldwin, C. Arrowitz, J. Del Rosso
participant (under the age of 18 years) prior to enrollment in the study. The original signed ICF for each patient participating in the study was retained in the study file and each patient received a copy of the signed form.
Study Design
Both studies were bilateral and double-blinded and were conducted from October 5, 2016, to November 2, 2016, at the Thomas J. Stephens & Associates, Inc. Colorado Research Center, Colorado Springs, Colorado.
Participants
Study 1: The first study included 35 participants (Male, n=6; Female, n=29) ages 16-70 years old (Mean, 57.1); 25% of the group (n=9) had mild dryness on the legs, and approximately 75% (n=26) had moderate-to-severe dryness on the legs.
Study 2: The second study included 33 participants (Male, n=12; Female, n=21) ages 16-70 years old (Mean, 50.9). Approximately 50% of the group (n=16) had mild dryness, and approximately 50% (n=17) had moderate-to-severe dryness on the legs.
Test Area and Application Procedures
Study 1: During the 10-day usage period of the study, participants applied Moisturizer A on the randomly assigned (right or left) leg and Moisturizer B on the opposite leg, once daily as directed. After 10 days, participants discontinued the use of the moisturizer and participated in a 5-day regression period during which time no moisturizer was applied.
Study 2: During the 10-day usage period of the study, participants applied Moisturizer B on the assigned (right or left) leg and Moisturizer C on the opposite leg, once daily as directed. After 10 days, participants discontinued the use of the moisturizer and participated in a 5-day regression period during which time no moisturizer was applied.
Enrollment Procedures
Prior to the start of the study, potential participants were screened over the telephone for eligibility criteria. Female and male participants between ages 16 and 70 years old were scheduled for eligibility screening at the clinic. Prospective participants were advised not to shave their legs and to avoid the application of any topical moisturizing product and use of cleansers with moisturizing properties on the legs for at least 3 days prior to visit 1.
At visit 1 (baseline), each prospective participant or the parent/guardian of minor prospective participants read and signed the informed consent form after the nature of the study was explained and any study-related questions were answered. Minor prospective participants (under the age of 18 years) signed an assent form indicating their agreement to participate
