Cost-Effectiveness Analysis of Ixekizumab vs Etanercept and Their Manufacturer-Recommended Dosing Regimens in Moderate to Severe Plaque Psoriasis
October 2017 | Volume 16 | Issue 10 | Original Article | 964 | Copyright © October 2017
Jeremy Udkoff MA MAS and Lawrence F. Eichenfield MD
Departments of Dermatology and Pediatrics, University of California, San Diego School of Medicine, San Diego, CA Department of Pediatric and Adolescent Dermatology, Rady Children’s Hospital, San Diego, CA
INTRODUCTION: Biologic therapies have revolutionized the treatment of psoriasis; however, their use is limited by costs. Ixekizumab was more effective than etanercept in the UNCOVER trials, and the Food and Drug Administration (FDA) approved ixekizumab for treating psoriasis. Evaluating the cost-effectiveness of these therapies is crucial for medical decision making and our objective was to determine the cost-effectiveness of various ixekizumab dosing frequencies compared with etanercept.
METHODS: We utilized published data from the UNCOVER comparative efficacy trials, including transitional probabilities and treatment response rates, to create a Markov model simulating the clinical course and cost-effectiveness of three treatment algorithms for patients with moderate to severe plaque psoriasis over 60-weeks: (1) ixekizumab every 2 weeks for 12 weeks then every 4 weeks, (2) ixekizumab every 4 weeks throughout the treatment period, (3) biweekly etanercept for 12 weeks then once weekly. We utilized a standard willingness-to-pay (WTP) threshold of $150,000 per quality adjusted life year (QALY) and Medicaid drug acquisition costs for our calculations.
RESULTS: Ixekizumab every 4 weeks was $28,681 (USD) less expensive than biweekly etanercept, and $21,375 less expensive, and 0.006 QALY less effective, than ixekizumab every 2 weeks-- a savings of $28.7 and $21.4 million, respectively, per 1,000 patients. A 95.6% cost reduction to $197.83 per dose is required for ixekizumab every 2 weeks to be more cost-effective than every 4 weeks. Biweekly etanercept requires a 29.5% cost reduction ($743.82 per dose) to be competitive with ixekizumab every 4 weeks.
DISCUSSION: This cost-effectiveness model utilizes strong input data but is a limited approximation of real-life scenarios. Treatment with ixekizumab every 2 weeks is unlikely to be cost-effective compared with ixekizumab every 4 weeks at current U.S. market prices. Yet, the U.S. FDA approval and manufacturer’s recommendation are for ixekizumab every 2 weeks. Accordingly, we suggested selecting biologic therapies using cost-effectiveness analyses.
J Drugs Dermatol. 2017;16(10):964-970.
The landscape of psoriasis therapies underwent a dramatic transformation with the introduction of efficacious biologic therapies. Many of these, such as etanercept (Enbrel®), a tumor necrosis factor-alpha blocker, are widely used for other diseases and adapted for use in psoriasis, while others, such as ixekizumab (Taltz®), an interleukin-17 antagonist, were recently introduced for plaque psoriasis. Although these treatments are extremely effective, they carry a large price tag. One dose of etanercept costs $1055.80 and ixekizumab is $4513.69 per dose.1 These are truly remarkable treatments and have the ability to change the lives of their users. In addition to the efficaciousness of these therapies, they are usually safe, well-tolerated, and not accompanied by the organ specific side effects of other systemic treatments.2 Psoriasis is one of the most common inflammatory skin diseases and affects approximately 2% of the U.S. population.3 The physical symptoms and discomfort, mental-health impact, comorbidities, and effect on social relationships of psoriasis have significant negative effects on patients leading to an overall diminished quality of life.4–7 In addition, psoriasis exerts a large economic burden on both society and the patient, and the utilization of cost-effective therapies that decrease disease severity are of the utmost importance.8–11 The recent UNCOVER-1, 2, and 3 trials compared ixekizumab to etanercept and placebo in the treatment of moderate to severe plaque psoriasis.12,13 Ixekizumab was found to be superior to etanercept and 48.1% more patients being treated with ixekizumab achieved a Psoriasis Area Severity Index (PASI) reduction of more than 75% (indicative of treatment responders) over 12-weeks of treatment in the UNCOVER-2 trial.13 An additional benefit of biologic therapies over conventional treatments is their infrequent administration. The United States Food and Drug Administration (FDA) approved a 12-week induction period with biweekly etanercept or ixekizumab every two weeks, followed by weekly etanercept or ixekizumab every four