POS0661 MAJOR COST SAVINGS ASSOCIATED WITH BIOLOGIC DOSE REDUCTION IN PATIENTS WITH INFLAMMATORY ARTHRITIS

Abstract

Background: Anti-TNF drugs have dramatically improved the management of infammatory arthritis (IA). Although the introduction of biosimilars have reduced the cost, chronic use of biologic agents has a high impact on healthcare expenditure. This study evaluated the cost effectiveness of a dose reduction strategy for the most commonly used anti-TNF drugs over a period of 10 years in patients with IA in remission. Objectives: The purpose of this study was to explore whether patients with Infammatory Arthritis (IA) (Rheumatoid Arthritis (RA), Psoriatic Arthritis (PsA) or Ankylosing Spondylitis (AS) would remain in remission after 10 year period, following a reduction in biologic dosing frequency and to calculate the cost savings associated with dose reduction. Methods: This prospective, non-blinded, non-randomised study was commenced in 2010. Patients with IA, Rheumatoid arthritis (RA),ankylosing spon-dylitis (AS) and Psoriatic arthritis (PsA) who were in remission as defned by disease activity indices (DAS28<2.6, BASDAI<4), and were offered Anti TNF dose reduction. Patients on etanercept were reduced from 50mg weekly to fortnightly, adalimumab 40mg once monthly instead of fortnightly. Patients were assessed for disease activity at 1, 4 and 10 years following reduction in dosing frequency.Cost saving was calculated by deducting the total annual cost of the biologic agent used over 10 years compared with the cost if the dosing interval had not changed. Results: Seventy nine patients with infammatory arthritis in remission were recruited. 57% had rheumatoid arthritis (n=45), 13% psoriatic arthritis (n=10) and 30% ankylosing spondylitis (n=24). 57% (n=45) were taking etanercept and 43% (n=34) adalimumab. The percentage of patients who maintained dose reduction at 10 years was 9% (n=7). Of the total 48 patients who were successfully dose reduced at year 1 (n=42), (69%, n=29) were able to maintain the dose reduction up to 4 years and 9% (n=7) maintained this dose reduction up to year 10. The estimated cost saving was €4,928 per patient per year. Estimated cost savings for 7 patients on reduced dose was €344,952.88 over 10 years. Conclusion: Anti TNF dose reduction strategy in patients with IA results in substantial cost savings. Implementation of a dose reduction strategy while monitoring of disease activity reduces the fnancial impact of the use of biologic therapies. Further studies should be done to identify which patients are more likely to remain in remission while on dose reduction.