415 Efficacy of 2% crisaborole ointment in 49 patients of atopic dermatitis with chronic hyperplasia lesions: a real-world study
Authors: Ma Chuan , Sun Jiachen , Liu Zilian , Cao Yuan , Wang Yuan  , Zhang Chunlei 
Published: June 2023

Abstract
Asian Atopic dermatitis (AD) presents as a mixed phenotype between the European American (EA) AD and psoriasis phenotypes, with highly atypical features for AD, including clearer demarcation of lesions, with more prominent scaling, lichenification, parakeratosis, hyperplasia and a unique cytokine profile with coactivation of the TH2 and TH17 axes. The cutaneous immune dysregulation in Chinese patients with AD usually exhibit remarkable increase in epidermal hyperplasia and parakeratosis, frequently observed in areas such as the hands, feet, knees and elbows. Currently, the response of chronic hyperplastic lesions to various conventional treatment modalities, including topical corticosteroids and topical calcineurin inhibitors, is not optimistic and often accompanied by various complications. As a Phosphodiesterase 4 (PDE4) inhibitor, crisaborole broadly inhibits inflammatory signaling pathways, and has demonstrated definite efficacy in AD partly due to its smaller molecular weight and higher transdermal absorption efficiency. This study aims to find the clinical efficacy of 2% crisaborole ointment monotherapy for chronic hyperplastic lesions of AD in real-world research in China. We retrospectively enrolled 49 patients with AD aged 12 years or older with chronic hyperplastic lesions and an Investigator’s Static Global Assessment (ISGA) score of mild or moderate. The patients were administered with 2% crisaborole ointment for twice-daily application until the complete clearance of lesion. The efficacy endpoints comprised the onset time of pruritus and lesion remission, and the time of complete lesion clearance. A 1-grade or more improvement of the VAS scores from baseline was defined as the pruritus remission. An improvement of 1 point or more of the ISGA scores was indicative of improved skin lesions. The ISGA score of 0 (clear) or 1 (almost clear) with a ≥2-grade improvement from baseline indicated complete remission of skin lesions. After subgrouping the patients by age and AD duration, we further compared differences in efficacy endpoints to explore potential influencing factors on the effectiveness of crisaborole. Two percent crisaborole ointment showed good efficacy for treating chronic hyperplasia lesions in Asian patients with AD, with minor irritation, early remission of pruritus [7.0 ( 3.0, 10.0) days] and lesions [7.0 (5.0, 10.0) days]. The median time for complete lesion clearance was 30 days. Two percent crisaborole ointment showed different efficacy in the different age. The onset of pruritus remission appeared to be more rapid in the elderly [2.0 (1.0, 10.0)] compared with the adolescents [4.0 (2.3, 6.5)] and the adults [7.0 (3.5, 10.0)], but with no statistically significant difference (P = 0.072). The adolescents had an earlier onset of lesion remission by approximately 3 days compared with the adults and the elderly (P = 0.044). Although the onset of pruritus remission for the adolescents and the adults was similar to their onset of lesion remission, the elderly seemed to experience significantly earlier pruritus remission compared with their lesion remission onset. There was no statistical difference in complete lesion clearance time among different age groups (P = 0.019). Commonly seen in Asian patients with AD, chronic hyperplasia lesions generally do not respond well to other topical medications. Two percent crisaborole ointment monotherapy is an effective treatment for chronic hyperplasia lesions in patients with AD of all age groups, and onset of pruritus and lesion remission is different in the different age group.