PBM Database Identifies Most Cost Effective Biologics for Rheumatoid Arthritis

Results of a claims-based analysis of a US pharmacy benefit manager (PBM) database show greater cost-effectiveness in subcutaneous versus intravenous (IV) biologics to treat rheumatoid arthritis (RA).

About 1.3 million US adults are diagnosed with the chronic inflammatory, autoimmune disorder, RA.¹ Biologic drugs are recommended to treat RA when a patient does not tolerate or does not adequately respond to treatment with nonbiologic disease-modifying antirheumatic drugs (DMARDs).

The most commonly used biologic drugs to treat RA include etanercept, adalimumab, and infliximab (all tumor necrosis factor inhibitors), and abatacept (a selective T-cell costimulation modulator). Etanercept and adalimumab are administered subcutaneously; infliximab and abatacept are administered via IV infusion. All of these agents are similar in efficacy, according to evidence from clinical trials and observational and meta-analyses.

PBM Analysis

A recent study analyzed pharmacy and medical claims data from the Medco Health Solutions PBM database to more closely examine how different biologic agents and delivery systems perform in terms of cost and efficacy. Investigators chose Medco’s PBM data set as a good representation of the general population because it includes millions of Americans covered by many health plans sponsored by both government and private payers.

Unlike previous PBM analyses of biologic claims that measured costs per treated patient² or dose escalation,³ this study used a validated algorithm for efficacy to determine cost per effectively treated patient. The study was published in ClinicoEconomics and Outcomes Research.

Study Sample

After applying inclusion and exclusion criteria, researchers identified a study sample population of 1090 patients in the United States who were effectively treated with biologic drugs for RA from 2007 to 2012. Seventy-eight percent of patients in the study sample were female, with a mean age of 49.7±9.4 years. The trial administered 785 patients with biologics subcutaneously, 305 received biologics by IV, 440 used etanercept, 345 used adalimumab, 201 used infliximab, and 104 used abatacept.

Efficacy of Biologics for RA

The validated algorithm analysis measured an overall efficacy rate of 32% for all biologic therapies for RA. Efficacy of the most commonly used biologic drug, etanercept (36%), was similar to adalimumab (35%; P=0.77) and significantly greater than abatacept (24%; P=0.02) and infliximab (22%; P<0.001).

Cost-Effectiveness by RA Drug Delivery System

Subcutaneous administration of biologics for RA was found to be significantly more effective than IV administration (36% versus 23%; P<0.001). Subcutaneous delivery also fared better in annual cost. Annual cost per effectively treated patient was $64,738 for subcutaneous biologics versus $80,408 for IV biologics.

Cost by RA Biologic Agent

This study’s validated algorithm measured the annual cost per effectively treated patient to be $62,303 for abatacept (IV), $62,841 for etanercept (subcutaneous), $67,226 for adalimumab (subcutaneous), and $90,696 for infliximab (IV). Relative to the most commonly used biologic drug, etanercept (100%), costs per effectively treated patient were 99% with abatacept, 107% with adalimumab, and 144% with infliximab.

Conclusion

Overall, this study found greater effectiveness and lower costs associated with subcutaneous- versus IV-administered biologics in the treatment of RA. Biologics delivered subcutaneously were 14% more effective than IV (36% versus 23%; P<0.001), with an annual cost savings of $16,000 per effectively treated patient.

• Helmick CG, Felson DT, Lawrence RC, et al. Estimates of the prevalence of arthritis and other rheumatic conditions in the United States. Part I. Arthritis Rheum. 2008;58(1):15—25. [PubMed]
• Wu N, Lee YC, Shah N, Harrison DJ. Cost of biologics per treated patient across immune-mediated inflammatory disease indications in a pharmacy benefit management setting: a retrospective cohort study. Clin Ther. 2014;36(8):1231—1241. [PubMed]
• Blume SW, Fox KM, Joseph G, Chuang CC, Thomas J, Gandra SR. Tumor necrosis factor-blocker dose escalation in rheumatoid arthritis patients in a pharmacy benefit management setting. Adv Ther. 2013;30(5):517—527. [PMC free article] [PubMed]