In Most Managed Care Patients, Annual TNF Treatment Costs Lower with Etanercept

A recent study compared the annual cost per treated patient for a health plan for patients taking etanercept, adalimumab, or infliximab.

Among tumor necrosis factor (TNF) blockers, etanercept has a lower cost per treated patient than adalimumab or infliximab therapies for patients with rheumatoid arthritis, psoriatic arthritis, ankylosing spondylitis, psoriasis and any other condition, or a combination of the conditions, the results of a study appearing in the October 2013 edition of Journal of Managed Care Pharmacy.

In patients with psoriasis alone, however, adalimumab proved to have a slightly lower cost per treated patient than etanercept or infliximab, the authors noted.

The findings may support formulary management decisions and highlight nonindex costs for managed care pharmacists.

“Examining these data separately allows managed care pharmacists to fully appreciate the important contribution of nonindex costs to total costs, as well as any differences between agents in these contributions,” the authors wrote.

“. . . These findings, when combined with the available evidence of the comparative efficacy and safety of TNF blockers in the treatment of rheumatoid arthritis, psoriasis, psoriatic arthritis, and ankylosing spondylitis, may be used by decision makers to support formulary decisions,” they added.

Researchers used data from the IMS LifeLink Health Plan Claims Database and included adults aged 18 to 64 with at least 1 insurance claim for etanercept, adalimumab, or infliximab between February 1, 2008, and July 5, 2010, in the study. Participants also needed diagnosis of rheumatoid arthritis, psoriasis, psoriatic arthritis, or ankylosing spondylitis, and were categorized as a new patient if there were no claims for the drugs prior to the study’s index date, or as a continuing patient if they had a claim prior to the study index date.

Patients with a diagnosis of juvenile idiopathic arthritis, Crohn’s disease, or ulcerative colitis were excluded from the study because the medications analyzed do not have those indications in common. In addition, researchers did not evaluate treatment effects or comparative statistical tests, as they were not pertinent to their analysis.

Researchers used April 2012 unit wholesale acquisition costs, as well as April 2012 update to the Medicare Physician Fee Schedule, to estimate budget impact. In addition, most participants were insured through commercial insurance plans or were self-insured, usually through either a preferred provider or an HMO plan.

The results showed etanercept was the most commonly used drug, followed by adalimumab, and infliximab.

In general, the annual TNF-blocker cost per treated patient was lowest for patients on etanercept, at $17,767 per treated participants for all participants in the study. Adalimumab therapy had an annual cost per treated patient of $19,272 of all treated participants, and infliximab had an annual cost per treated patient of $24,273.

In newly treated participants across all conditions, the annual cost per treated patient was $17,270 for etanercept, $17,959 for adalimumab, and $21,482 for infliximab. Meanwhile, participants on continuing treatment across all conditions saw annual costs per treated patient of $18,203 for etanercept, $20,453 for adalimumab, and $25,468 for infliximab.

The same trend of lower per patient per year costs for etanercept, adalimumab, and infliximab extended to the majority of conditions examined in the study, with the annual cost of therapy per treated patient being 3% to 31% greater for adalimumab than etanercept and 26% to 72% greater for infliximab than etanercept, the research noted.

Psoriasis without concomitant conditions was the only condition in which etanercept was not the least expensive therapy. In those patients, the cost of adalimumab was 6% lower than the cost of etanercept, although etanercept was still less expensive that infliximab. In this case, researchers noted a 3-month etanercept loading dose for patients with psoriasis that would likely increase overall costs in the first year of therapy.

The authors disclosed that Amgen Inc participated in study design, data analysis, and manuscript preparation. In addition, authors Crystal Watson, George J. Joseph, and David J. Harrison report being employed by Amgen at the time the study was conducted and the manuscript prepared.