Economic Evaluation of Dupilumab for Moderate-to-Severe Atopic Dermatitis: A Cost-Utility Analysis

July 2018 | Volume 17 | Issue 7 | Original Article | 750 | Copyright © July 2018


Marita Zimmermann MPH PhD,a David Rind MD MSc,b Rick Chapman PhD, MS,b Varun Kumar MBBS MPH MSc,b Sonya Kahn MPH,b Josh Carlson PhD MPHa

aPharmacy Department, University of Washington, Seattle, WA bInstitute for Clinical and Economic Review, Boston, MA

Abstract
Background. Moderate-to-severe atopic dermatitis can be difficult and costly to treat. The long-term health and economic outcomes of a new therapy, dupilumab, have yet to be evaluated. We aimed to identify the cost-effectiveness of dupilumab compared to usual care in moderate-to-severe atopic dermatitis. Methods. We compared dupilumab to usual care with emollients for adults with moderate-to-severe atopic dermatitis inadequately controlled with topical therapy, or for whom topical therapies were medically inadvisable. Subpopulations of moderate and severe patients were examined separately. We used a lifetime Markov model from a US payer perspective with health states categorized by the percent decrease in Eczema Area and Severity Index (EASI) score after a patient began an intervention: at least a 50% decrease (EASI 50), 75% decrease (EASI 75), 90% decrease (EASI 90), or no response. Results. The expected lifetime cost for patients treated with dupilumab was $509,600, including $267,800 in dupilumab drug costs and $241,800 in other healthcare costs. Average lifetime cost for usual care was $271,500. Dupilumab provided an additional 1.91 quality-adjusted life years (QALYs) over the remaining lifetime of a patient, leading to an incremental cost-effectiveness ratio (ICER) of $124,500. The ICER was lower for patients with severe atopic dermatitis ($95,800) than those with moderate atopic dermatitis ($160,000). Key drivers of the model were utility values for quality-of-life for non-responders, and the price of dupilumab. Conclusions. This study was limited by data for health outcomes and costs over long time periods, particularly stratified by severity. We estimated that dupilumab improved health outcomes compared to usual care but with additional costs, with an ICER below commonly cited thresholds for cost-effectiveness. Dupilumab was projected to be more cost-effective in patients with severe atopic dermatitis, but even in patients with moderate atopic dermatitis, the ICER remained below the upper range of commonly cited thresholds. J Drugs Dermatol. 2018;17(7):750-756.

INTRODUCTION

Atopic dermatitis is a chronic skin condition causing itching, dry, and painful skin, that affects 11% of children and 3-7% of adults in the United States.1-3 Atopic dermatitis can dramatically affect a patient’s quality of life.4 Itching often disrupts sleep leading to daytime drowsiness5 and irritability, which can lead to psychological stress and impaired performance in school and at work. Additionally, aesthetic changes to visible skin can lead to social stress and isolation.4Most patients with atopic dermatitis use bland moisturizers and emollients for treatment, along with meticulous and often difficult or lengthy skin care routines. Patients also focus on avoidance of triggers such as foods, products, or activities that increase their disease activity. Intermittently, patients use topical corticosteroids, and may implement long-term maintenance with a topical calcineurin inhibitor.6 Unfortunately, over time, corticosteroid use may be associated with moderate or severe adverse events including adrenal suppression, telangiectasias, increased hair, skin tears, easy bruising, poor wound healing, acne and rosacea, and thinning/atrophic changes, which can be permanent.7-9 Some patients may use phototherapy or systemic immunomodulatory agents, but few supportive data are available as to the efficacy of these therapies for atopic dermatitis.Dupilumab (Dupixent™, Sanofi-Regeneron) is a monoclonal antibody against interleukin-4 receptor alpha that has been evaluated as a novel systemic therapy for moderate-to-severe atopic dermatitis in adults.10 Dupilumab may provide an important therapeutic option for many patients with moderate-to-severe atopic dermatitis who have not had an adequate response to treatment. Key trials for dupilumab included patients >18 years old with moderate-to-severe atopic dermatitis with an Investigator’s Global Assessment (IGA) score of 3 or 4, an EASI ≥ 16 at baseline, and involvement of at least 10% of the body surface area, for whom topical treatment provided inadequate control or was medically inadvisable.10 In these trials, dupilumab consistently met prespecified Investigator’s Global Assessment targets representing successful outcomes in 30-44% of patients, compared to 2-12% for placebo, as well as substantially increasing the likelihood of achieving EASI 75