Prescription Market Share and Treatment Patterns in Atopic Dermatitis: A Retrospective Observational Study Using US Insurance Claims

Abstract

Introduction: There is limited real-world evidence on the treatments for atopic dermatitis (AD) since dupilumab was approved in 2017. The objective of this study was to assess market share of drugs commonly prescribed for the treatment of AD and describe treatment patterns in patients diagnosed with AD.

Methods: This was a retrospective, observational study in adult patients with an ICD-10 diagnosis of AD between 2017 and 2019 using insurance claims data in the US population.

Results: Market share cohorts consisted of 75,794 (2017) and 89,618 (2018) patients. Treatment patterns cohort had 68,588 patients with 63.56% female, mean (SD) age 43.54 (15.96) years, and mean (SD) Quan CCI 0.31 (0.85). Topicals had two-thirds market share by prescription volume (2017 = 65.56%; 2018 = 63.63%). Corticosteroids were the most prescribed topical (2017 = 71.94%; 2018 = 72.04%) and systemic (2017 = 30.59%; 2018 = 30.23%) drug class. Dupilumab had the highest medication adherence (proportion of days covered [PDC] ≥ 80%; 60.74%) and persistence (17.39%), lowest discontinuation rate (23.32%), and longest mean (SD) days on therapy 148.20 (101.77).

Conclusion: Topicals are the primary treatment for patients with AD, even though systemic users have higher medication adherence (PDC). Systemics provide a treatment alternative to topicals.

Keywords: Atopic dermatitis; Prescription market share; Retrospective; Systemic therapy; Treatment patterns.

Fig. 1

Atopic dermatitis patient selection criteria and attrition. *Percentages are of patients selected in the first step. AD, atopic dermatitis; ICD-9/10, International Classification of Diseases; n, number of patients; NDC, National Drug Code

Fig. 2

Persistence measured as length of therapy^a in patients with atopic dermatitis. ^aLength of therapy was calculated based on the number of days of continuous therapy from the index date until the end of the follow-up, allowing for the 60-day gap between fills, reported by drug class. IL4/13i interleukin-4/13 inhibitor; PDE-4 phosphodiesterase-4 inhibitors; SCS systemic corticosteroids; SIS systemic immunosuppressants; TCI topical calcineurin inhibitors; TCS topical corticosteroids. Error bars indicate standard error of the mean