Treatment of Keratosis Pilaris with a Novel Polymer-based Skin Coating JH Miller1, SD Bangert1, BK Bhatt2, JE Morrison2, G Siegel2 and AA Hebert1 Dept. Dermatology, University of Texas Medical School-Houston, Houston, TX1 and Biomedical Development Corp., San Antonio, TX2 Poster #P412 National Institutes of Health / National Institute of Arthritis Musculoskeletal and Skin Diseases. SBIR#R43AR052213 Sponsored by Epikeia Incorporated Contact: gsiegel@biodevcorp.com Treatment of Keratosis Pilaris with a Novel Polymer-based Skin Coating BACKGROUND Keratosis pilaris (KP), a disorder of keratinization, is a benign, inherited skin disorder that presents as grouped, horny follicular papules and tends to occur as excess keratin accumulates around hair follicles on the proximal extensor surfaces of the arms, the upper lateral thighs, or the buttocks. This study evaluated treatment of KP using a polymer-based coating that is applied directly to the skin as a liquid solution that dries in seconds to form a clear thin film. OBJECTIVE The purpose of this study was to evaluate a polymer-based film-forming technology as a treatment for keratosis pilaris in a 12-week clinical trial. The product is an acetone and polymer-based skin coating that is applied to the skin as a liquid that rapidly dries (~15 – 30 seconds) to form a thin film. The coating can be used for local drug delivery of a variety of active compounds including salicylic acid, which was used for this study at a 2.0% concentration. Treatment of Keratosis Pilaris with a Novel Polymer-based Skin Coating METHODS The study was designed as a double-blind, randomized left/right comparison to evaluate the efficacy of a polymer-based skin coating with or without salicylic acid to treat KP. Over a 12-week period, subjects with bilateral keratosis pilaris applied the polymer coating to one arm and the polymer coating containing salicylic acid to the contralateral arm. Thirty subjects having bilateral KP were enrolled in the study and treatment was randomized by left/right assignment. Measurements and subjective evaluation by the participants were completed at baseline and weeks 2, 4, 8, and 12. Treatment of Keratosis Pilaris with a Novel Polymer-based Skin Coating METHODS (Continued) Parameters for KP evaluation included scale and roughness, clinical impression of treatment response, and subject impression of treatment response (Tables 1 and 2). Table 1. Scoring Criteria for Scale and Roughness Score Description 0 Absent 1 Slight 2 Moderate 3 Severe Table 2. Scoring Criteria for Clinician and Subject Impression of Treatment Response Score -1 0 1 2 3 4 Description Worse No change Slight Change Moderate Improvement Marked Improvement Cleared Treatment of Keratosis Pilaris with a Novel Polymer-based Skin Coating ANALYSIS Box plots and frequencies were performed to identify outliers and the distribution and demographic characteristics of the study population. Cross-tabulations were run on demographic variables and efficacy measures. The Signed-Ranks test was used to assess changes in ordinal and interval variables; the Student T test was used to assess differences in continuous variables. The Friedman test was used to compare ordinal repeated measures. Significance was ascribed to a p value ≤ 0.05. RESULTS Twenty-two subjects completed the study and were considered evaluable. Both treatments demonstrated significant improvement (p<0.008) with regard to scale and roughness, and clinical evaluation of treatment (p< 0.0001). With regard to physician and subject impression of treatment, moderate and marked improvement was observed over time. Treatment of Keratosis Pilaris with a Novel Polymer-based Skin Coating RESULTS (Continued) Of note, there were 19 study sites (arms) that presented with either moderate or severe ratings for scale and roughness at baseline. By week 12, all but 3 of the sites had only either slight or no scale and roughness (Figure 1). Significant differences were not observed between the salicylic acid and polymer-only treatment groups. Treatment of Keratosis Pilaris with a Novel Polymer-based Skin Coating RESULTS Subject 10 at Baseline and 12 weeks after treatment with the polymer coating containing salicylic acid. Remnants of the polymer coating treatment appear on the arm in the 12 week photo. Baseline Baseline Visit55 Visit (12weeks) weeks) (12 Treatment of Keratosis Pilaris with a Novel Polymer-based Skin Coating SELECTED PHOTOS Subject 12 at Baseline and 12 weeks after treatment with polymer coating only (no salicylic acid). Baseline Visit 5 (12 weeks) Treatment of Keratosis Pilaris with a Novel Polymer-based Skin Coating SELECTED PHOTOS Subject 06 at Baseline and 2 weeks after treatment with polymer coating only (no salicylic acid). Baseline Visit 1 (2 weeks) Treatment of Keratosis Pilaris with a Novel Polymer-based Skin Coating SELECTED PHOTOS Subject 06 at Baseline and 2 weeks after treatment with polymer coating containing salicylic acid. Remnants of the polymer coating treatment appear on the arm in the 2 week photo. Baseline Visit 1 (2 weeks) Treatment of Keratosis Pilaris with a Novel Polymer-based Skin Coating DISCUSSION There is currently no cure or universal treatment for disorders of keratinization such as keratosis pilaris. In general, moisturizers alone or in combination with keratolytic agents such as urea, salicylic acid, and alpha hydroxy acids are used. Use of oral retinoids have been effective in improving scale appearance; however, redness and irritation are frequent side effects. The novel polymer-based coating evaluated in this trial offers a new treatment for keratosis pilaris, and may be useful for other disorders of keratinization such as ichthyosis. CONCLUSION These novel polymer-based coatings significantly improve keratosis pilaris.