Cost of tumor necrosis factor blockers per patient with rheumatoid arthritis in a multistate Medicaid population

Abstract

Machaon Bonafede,1 George J Joseph,2 Neel Shah,2 Nicole Princic,1 David J Harrison2 1Truven Health Analytics, Cambridge, MA, 2Amgen Inc., Thousand Oaks, CA, USA Background: The purpose of this study was to estimate the annual cost per treated patient for the tumor necrosis factor (TNF) blockers, etanercept, adalimumab, and infliximab in rheumatoid arthritis (RA) patients covered by Medicaid. Methods: The MarketScan Medicaid Multistate Database was used to identify adult RA patients who used etanercept, adalimumab, or infliximab (index agents) from 2007 to 2011. The index date was the first claim preceded by 180 days and followed by 360 days of continuous enrollment. Patients with other conditions for which these agents are approved by the US Food and Drug Administration were excluded. “Continuing” patients had one or more pre-index claim for their index biologic, and "new" patients did not. Cost per treated patient was calculated in the 360 day post-index period for each index agent as the total index drug and administration cost to the payer and the costs of switched-to agents divided by the number of patients who received the index agent. Results: A total of 1,085 patients met the study criteria. Forty-eight percent received etanercept (n=521); 37% received adalimumab (n=405); and 15% received infliximab (n=159). Patient characteristics were similar across groups (mean age 47.4 years, 83% female). The annual cost per treated patient was lowest for etanercept ($18,466), followed by adalimumab ($20,983) and infliximab ($26,516). For all agents, annual costs were lower for new patients ($17,996 for etanercept, $18,992 for adalimumab, and $24,756 for infliximab) than for continuing patients ($19,004 for etanercept, $24,438 for adalimumab, and $28,127 for infliximab). Conclusion: Etanercept had lower costs per treated patient than adalimumab or infliximab in both new and continuing Medicaid enrollees with RA. Keywords: cost, tumor necrosis factor, rheumatoid arthritis, Medicaid