Testing A New Petrolatum-Depositing Body Wash In A Regression-Type Protocol
KD Ertel1, PhD; PM Hartwig1, BS; RA Bacon1, BS; HL Focht1, BChE; AL Newman1, BS; T Stoudemayer2, BS; I Sadiq2, MS; AM Kligman2, MD, PhD The Procter & Gamble Company, Cincinnati, OH1 and S.K.I.N., Incorporated, Conshohocken, PA2
The regression method for testing the efficacy of leave-on moisturizers was first described in 1978.1 Numerous variants of this original procedure exist; these generally involve daily, controlled leave-on application of moisturizer for several weeks followed by a regression period during which treatment is stopped and the skin's return to a baseline state is monitored by visual evaluation and by measuring stratum corneum hydration. Moisturizing personal cleansers are not routinely tested under protocols involving extended regression because of showering habits (i.e. daily use) and the fact that they are rinsed from the skin. We developed a new petrolatum-depositing body wash technology with excellent in-use aesthetics compared to current moisturizing body wash products. In addition, controlled application testing shows that this new body wash technology provides improved moisturization efficacy compared to current products. Given this outcome we decided to test this new body wash technology under a regression-type protocol.
To assess the ability of the new petrolatum-depositing body wash to provide an extended skin moisturization benefit under a regression-type protocol employing ad lib usage rather than controlled application conditions.
• A randomized, blinded ad lib use pilot study was conducted to compare the new petrolatum-depositing body wash to a regular body wash based on a similar surfactant chassis. The 5-week study comprised 4 weeks of daily home-use and 1 week of regression. •Ten healthy adult females with dry leg skin were enrolled and gave informed consent. Moisturizer application to the legs and other activities that could impact leg skin condition were prohibited. Leg shaving was restricted. •During the 4-week treatment phase subjects used the regular body wash for cleansing their bodies and one leg; the other leg was washed with the petrolatum-depositing body wash. Color-coded puffs were supplied with each product. Subjects were required to shower at least once daily with the test products. •During the 1-week regression phase subjects used the regular body wash for cleansing their bodies but did not use the product directly on either leg. •Leg dryness was evaluated visually (0-4 scale) at baseline, after 2 and 4 weeks of test product use, and at the end of the 1-week regression. Skin capacitance (Corneometer CM-825) was measured at baseline, the 4-week, and regression visits. The treatment and regression phase evaluations were made 18-24 hours after the previous shower. Subjects acclimatized in a room with controlled environmental conditions for at least 30 minutes prior to evaluation. •Data were analyzed by mixed model techniques adjusting for study design parameters.
• The petrolatum-depositing body wash produced significantly greater dry skin improvement than the regular body wash at the 2-week and 4-week treatment phase evaluations. •The greater dry skin benefit provided by the petrolatum-depositing body wash remained even after a week of regression.
• Consistent with the visual assessments, the petrolatum-depositing body wash produced significantly greater improvement in stratum corneum hydration than the regular body wash at 4-week treatment evaluation. •The hydration benefit from the petrolatum-depositing body wash was directionally better than that of the regular body wash at the end of the regression phase.
The new petrolatum-depositing body wash provided a significant moisturization benefit compared to a regular body wash under ad lib usage conditions, even after a week of regression. This demonstrates the new body wash technology's ability to improve dry skin under normal use conditions involving daily showering.