Long-Term Treatment Patterns Among Patients With Psoriasis Treated With Ixekizumab or Adalimumab: A Real-World Study

April 2022 | Volume 21 | Issue 4 | Original Article | 399 | Copyright © April 2022


Published online March 28, 2022

Andrew Blauvelt MD MBA,a Nianwen Shi PhD,b Mwangi J. Murage PhD MPH,c Terri Lynn Ridenour MBA BSN,c Carolyn R. Lew PhD,b Najwa Somani MD,c Baojin Zhu PhD,c Nicole M. Zimmerman MS,b Scott A. Kern RN,c Russel T. Burge PhDc,d

aOregon Medical Research Center, Portland, OR
bIBM Watson Health, Cambridge, MA
cEli Lilly and Company, Indianapolis, IN
dUniversity of Cincinnati, Cincinnati, OH

Abstract
Background: There is a paucity of long-term real-world evidence comparing the effectiveness of ixekizumab (IXE) and adalimumab (ADA). We compared real-world treatment patterns of IXE-treated and ADA-treated patients with psoriasis over 24 months in the United States.
Methods:
A retrospective observational study was conducted using IBM Watson Health MarketScan® databases. Adult patients with psoriasis having ≥1 claim for IXE or ADA from March 1, 2016 – October 31, 2019 were identified. Inverse probability of treatment weighting (IPTW) was used to address cohort imbalances. Cox proportional hazards models were used to estimate the risks of non-persistence, discontinuation, and switching. Logistic regression was used to estimate odds of high adherence. Persistence, adherence, discontinuation, reinitiation, and dosing and switching rates were also analyzed.
Results: The final cohorts comprised 475 IXE users and 3159 ADA users over 24 months. IXE users demonstrated higher adherence (36.3% vs 28.8%; P<0.001) and persistence rates (35.2% vs 28.8%; P=0.004), and a lower discontinuation rate (59.1% vs 65.3%; P=0.007) compared to ADA users. IXE users had a higher likelihood of being treatment-adherent compared to ADA users (OR=1.52, 95% CI: 1.24–1.87), a lower risk of non-persistence (HR=0.84, 95% CI: 0.75–0.95), and a lower risk of discontinuation (HR=0.83, 95% CI: 0.74–0.94), respectively. Switching rates were similar in both groups (31.2% vs 30.0%; P=0.608).
Conclusion: IXE users had better treatment adherence and persistence, and a lower risk of discontinuation compared to ADA users over 24 months. There was no difference in the risk of switching between IXE and ADA.

J Drugs Dermatol. 2022;21(4):399-407. doi:10.36849/JDD.6336

INTRODUCTION

Psoriasis is a chronic systemic inflammatory condition characterized by erythematous, scaly plaques on the skin. It is associated with several comorbidities that impact quality of life, well-being, and life span of patients.1,2 Currently available treatment options for moderate-to-severe plaque psoriasis include oral drugs, biologic therapies, and phototherapy.3-5 Two commonly utilized biologics for psoriasis include adalimumab (ADA) and ixekizumab (IXE). ADA is a human monoclonal antibody that inhibits tumor necrosis factor-α (TNF-α).6-8 IXE is a human monoclonal antibody that targets interleukin 17A (IL-17A).6-8 Short-term Phase III studies have shown that 63–80% of patients receiving ADA and 87–90% of patients receiving IXE achieved 75% reduction in Psoriasis Area and Severity Index.7-14 Both ADA and IXE have been separately shown in clinical trials to maintain long-term efficacy over 5 and 7 years, respectively.15-16

Long-term effectiveness of drugs, including ADA and IXE, in real-world settings is more difficult to assess. Data are limited and can be conflicting or contradictory to clinical trial findings.12 Additionally, there are no long-term real-world studies comparing effectiveness of both medications. Previously, we compared real-world treatment pattern outcomes for IXE and ADA users with a variable length follow-up period of 14 and 16.5 months, respectively.17 Here, we expanded the analyses and compared adherence, persistence, switching, discontinuation, and reinitiation outcomes between IXE and ADA users with psoriasis in real-world settings over 24 months.

MATERIALS AND METHODS

Study Design and Data Sources
A retrospective observational study was conducted in adult patients with psoriasis who were using either IXE or ADA