Cost-Effectiveness and Budget Impact of Lumacaftor/Ivacaftor in the Treatment of Cystic Fibrosis

Abstract

Background: Cystic fibrosis (CF) is a chronic, progressive, genetic disease affecting more than 30,000 people in the United States and 70,000 people globally. The goals of treatment are to slow disease progression, reduce pulmonary exacerbations, relieve chronic symptoms, and improve the patient's quality of life. Lumacaftor/ivacaftor is a new therapy for CF that has demonstrated good clinical outcomes, including improved absolute percentage predicted forced expiratory volume in 1 second (FEV₁%). However, given the high cost of therapy, there is a need to evaluate the overall value of lumacaftor/ivacaftor in CF management.

Objectives: To (a) conduct a cost-effectiveness analysis (CEA) of lumacaftor/ivacaftor to understand the overall effectiveness of the drug compared with its costs and (b) conduct a budget impact analysis (BIA) to understand the potential financial effect of introducing a new drug in a health plan.

Methods: Two static decision models were developed using Microsoft Excel to evaluate the cost-effectiveness and budget impact of lumacaftor/ivacaftor over a 1-year time frame from a payer perspective. Model inputs included drug costs (wholesale acquisition costs), drug monitoring schedules (package inserts), drug monitoring costs (Centers for Medicare & Medicaid physician fee schedule and published literature), FEV₁% predicted and pulmonary exacerbation values (clinical trials), and cost to treat pulmonary exacerbations (published literature). The outcomes in the CEA included total cost of therapy; average cost-effectiveness ratio (ACER), defined as cost per FEV₁% predicted; and incremental cost-effectiveness ratio (ICER), defined as the difference in the ratio of cost per FEV₁% predicted of lumacaftor/ivacaftor and placebo. Outcomes in the BIA included total budget impact; cost per member per month (PMPM), defined as total budget impact per hypothetical plan population; and cost per treated member per month (PTMPM), defined as total budget impact per target CF population. All costs were adjusted to 2016 dollars, and one-way sensitivity analyses were conducted to test the model robustness given uncertainty in model inputs and study assumptions.

Results: The annual cost of therapy per patient for lumacaftor/ivacaftor was $379,780. The ACER for lumacaftor/ivacaftor was $151,912, while the ICER for lumacaftor/ivacaftor compared with placebo was $95,016 per FEV₁% predicted. The annual total budget impact due to the inclusion of lumacaftor/ivacaftor on the health plan formulary was $266,046. The PMPM cost was $0.02 and the PTMPM cost was $6.21.

Conclusions: In patients with CF, lumacaftor/ivacaftor has demonstrated better clinical effectiveness compared with placebo alongside an increased drug acquisition cost. However, the therapy may be a viable alternative to existing standard therapy over a short time horizon. Health care payers, both private and public, need to evaluate the cost-effectiveness and the financial effect when considering expansion of new drug coverage in CF management.

Disclosures: No outside funding supported this study. Covvey and Kamal have received research funding from Novartis Pharmaceuticals. Covvey, Giannetti, and Kamal have received research funding from the College of Psychiatric and Neurologic Pharmacists. Kamal serves as a consultant to the Lynx Group (Cranbury, NJ) and Manticore Consulting Group (Scottsdale, AZ). Mukherjee has nothing to disclose. A related poster abstract was presented at the AMCP Managed Care & Specialty Pharmacy Annual Meeting; March 27-30, 2017; Denver, CO.

FIGURE 1

Tornado Plot for One-Way Sensitivity Analysis of Cost-Effectiveness of Lumacaftor/Ivacaftor

FIGURE 2

Tornado Plot for One-Way Sensitivity Analysis of Budget Impact of Lumacaftor/Ivacaftor