AB0496 Tumor necrosis factor (TNF)-inhibitor dose escalation in rheumatoid arthritis (RA) patients in a united states (US) pharmacy benefits management (PBM) setting:
Authors: S.W. Blume, K.M. Fox, G. Joseph, C.-C. Chuang, J. Thomas, S.R. Gandra
Journal: Annals of the Rheumatic Diseases (2013)

<h3>Background</h3> In the US, Pharmacy Benefits Management (PBM) companies act as third-party administrators who manage prescription benefits for health insurance companies and self-insured entities. Research in commercial health plans has shown higher rates of dose increases with some TNF-inhibitors than others, but the impact of dose escalation in a PBM setting that may have more intensive cost management is not clear. <h3>Objectives</h3> This study investigated multiple measures of dose escalation among RA patients who were either initiating or continuing treatment with TNF-inhibitor therapy with etanercept (ETN) and adalimumab (ADA) in a PBM setting. <h3>Methods</h3> A retrospective study using integrated pharmacy and medical claims from the Medco database was conducted; Medco is one of the largest PBMs in the US. Adult (age 18-64 yrs) RA patients with a pharmacy claim for ETN or ADA therapy between 2007 and 2009, continuous enrollment in the Medco PBM for ≥6 months before and ≥12 months after first (index) claim, ≥12 months persistence (no switching or ≥60 day gap in TNF-inhibitor therapy), and who started at ≥ the recommended label dose were eligible. Patients were excluded if they had other conditions that were also treated with TNF-inhibitors (e.g. psoriasis) or other conditions where TNF-inhibitors use was not prudent (e.g. cancer). Patients were classified as new patients if they had no claim for a TNF-inhibitor in the 6 months prior to index TNF-inhibitor date; otherwise, they were classified as continuing patients. Dose escalation was defined as: 1) average weekly dose ≥110% of recommended label dose; 2) average subsequent dose ≥130% of starting dose; 3) last dose ≥110% of starting dose; 4) two or more consecutive instances of dose ≥130% of starting dose; or 5) any instance where dose increase connoted additional syringe or vial use. Differences in proportions of dose escalators were evaluated using chi-square tests. <h3>Results</h3> Data from 1,260 ETN and 852 ADA patients with RA were analyzed. Across all measures of dose escalation, patients on ETN had a significantly lower rate of dose escalation (<i>P</i>&lt;0.001) than patients on ADA (Table). <h3>Conclusions</h3> Several different measures of evaluating dose escalations were applied to data from a PBM setting that represented real-world use of TNF-inhibitors. Each method consistently showed that RA patients, both new and continuing on ETN, had significantly lower rates of dose escalation than patients on ADA. <i>This study was sponsored by Immunex, a wholly owned subsidiary of Amgen Inc. and by Wyeth, which was acquired by Pfizer Inc.</i> <h3>Disclosure of Interest</h3> S. Blume Consultant for: Amgen Inc., K. Fox Consultant for: Amgen Inc., G. Joseph Shareholder of: Amgen Inc., Employee of: Amgen Inc., C.-C. Chuang Consultant for: Amgen Inc., J. Thomas Shareholder of: Amgen Inc., Employee of: Amgen Inc., S. Gandra Shareholder of: Amgen Inc., Employee of: Amgen Inc.