Cosmeceutical Regimen Equally Effective, Better Tolerated Than Tretinoin A Randomized, Controlled Comparative Study of the Wrinkle Reduction Benefits of a Cosmetic Niacinamide/Peptide/Retinyl Propionate Product Regimen vs. a Prescription 0·02% Tretinoin Product Regimen

Background: Cosmeceuticals are preparations claiming to possess biologic activity but are marketed as cosmetics. These products often contain multiple "active" ingredients with vague claims of efficacy. However, many cosmeceutical products do contain retinoids, which are likely to have similar activity to tretinoin, although less clinical evidence is available to support the contention that these other retinoids give cosmetic benefits. Patients frequently ask if these over-the-counter retinoids are equivalent to tretinoin. I respond that they probably have somewhat similar efficacy, but less clinical data are available. Objective: To compare the efficacy of a cosmetic moisturizer regimen versus a prescription regimen with 0·02% tretinoin for improving the appearance of facial wrinkles. These investigators were employed by the Proctor and Gamble Company. Design: Randomized clinical trial. Participants: 196 women aged 40 to 65 years with Fitzpatrick skin types I to III and moderate to moderately severe periorbital wrinkles. Methods: Subjects were randomized to either tretinoin once per day and sunscreen or the niacinamide/peptide/retinyl propionate regimen, which consisted of 3 different Proctor and Gamble products containing sunscreen, niacinamide, peptides, antioxidants, and a retinoid (0.3% retinyl propionate). Prior to the start of the study, 25 subjects in each group agreed to undergo their treatment regimen for 24 weeks rather than 8 weeks. Perioral wrinkles were assessed by expert grading and image analysis of digital images of subjects' faces and by a self-assessment questionnaire. Product tolerance was assessed via clinical erythema and dryness grading and self-assessment. Results: The cosmetic regimen produced superior improvement in periocular wrinkles at 8 weeks, but the 2 regimens produced similar improvement at 24 weeks. Tretinoin, but not the cosmetic regimen, was associated with the typical retinoid side effects of erythema and dryness. Tretinoin produced an increase in transepidermal water loss at 8 weeks, indicating some breakdown of the skin barrier. This skin barrier breakdown largely resolved by 24 weeks. Conclusions: The specific cosmeceutical regimen followed in this study can produce similar improvement in periocular wrinkles as tretinoin with less transient irritation. Reviewer's Comments: The obvious problem with the study is that it compared a regimen containing multiple ingredients with tretinoin so it is very difficult to determine what is mediating the anti-wrinkle activity of the cosmetic regimen. No biopsies were performed, so it is unclear whether the cosmetic has the known effects of tretinoin on dermal collagen. Niacinamide is known to improve skin barrier function, so an intriguing possibility is that niacinamide blunts some of the irritancy of the retinoid. Hopefully, future studies will address the specific molecule mediating the efficacy and reduced irritancy of the cosmetic regimen. (Reviewer-Michael S. Kolodney, MD, PhD).