National and regional dose escalation and cost of tumor necrosis factor blocker therapy in biologic-naïve rheumatoid arthritis patients in US health plans.

AbstractObjective:This study examined the proportion and magnitude of dose escalation nationally and regionally among rheumatoid arthritis (RA) patients treated with TNF-blockers and estimated the costs of TNF-blocker therapy.Methods:This retrospective cohort study used claims data from US commercially-insured adult RA patients who initiated adalimumab, etanercept, or infliximab therapy between 2005–2009. Biologic-naive patients enrolled in the health plan for ≥6 months before and ≥12 months after therapy initiation were followed for 12 months. Dose escalation was assessed using three methods: (1) average weekly dose > recommended label dose, (2) average ending dispensed dose > maintenance dose, and (3) average dose after maintenance dose > maintenance dose. Annual cost of therapy included costs for mean dose and drug administration fees.Results:Overall, 1420 etanercept, 874 adalimumab, and 454 infliximab patients were included. A significantly lower proportion of etanercept-treated patients had dose esca...