The Clinical Anti-aging Effects of Topical Kinetin and Niacinamide in Asians: a Randomized, Double-blind, Placebo-controlled, Split-face Comparative Trial

Background: Kinetin and niacinamide are used in the cosmetic industry as anti-aging agents. Neither the interactive/additive effects of these compounds nor the anti-aging efficacy on Asian skin has been studied. Objective To assess the clinical anti-aging effects and efficacy differences between kinetin plus niacinamide and niacinamide alone vs. vehicle placebo in an Asian cohort.

Methods: Fifty-two Taiwanese subjects were enrolled in a randomized, double-blind, placebo-controlled, split-face comparative study. Group 1 subjects were treated with kinetin 0.03% plus niacinamide 4%, whereas group 2 subjects received niacinamide 4%. The treatment formulation was applied on one side of the face, whereas a placebo was applied on the other for a period of 12 weeks. We used noninvasive biometrological instruments to evaluate a variety of skin parameters at baseline and at weeks 4, 8, and 12.

Results: Persistent and significant reductions in spot, pore, wrinkle, and evenness counts were found at weeks 8 and 12 in group 1. A significant increase in corneal hydration status was also evident at week 12, whereas persistent decreases in erythema index were apparent at 8 and 12 weeks. In group 2, significant reductions in pore and evenness counts at week 8 and wrinkle counts at week 12 were noted.

Conclusion: We found kinetin and niacinamide exert a synergistic anti-aging effect. Our data suggest that these compounds have multiactive, multifunctional, and pluripotent effects on skin. They are also both promising to be included in the cutaneous anti-aging cosmeceuticals in the future.