FRI0139 Comparative safety of abatacept in rheumatoid arthritis with copd: a real-world population-based observational study
Authors: S. Suissa, P. Ernst, S. Dell’Aniello, S. Shen, T.A. Simon
Journal: Annals of the Rheumatic Diseases (2018)

<h3>Background</h3> In the ASSURE trial (NCT00048932) comparing abatacept with placebo for the treatment of RA, there was an increased incidence of respiratory serious adverse events (SAEs; COPD exacerbation/worsening, bronchitis and pneumonia) in those receiving abatacept among the subgroup of 54 patients with a history of chronic obstructive pulmonary disease (COPD).<sup>1</sup> <h3>Objectives</h3> To assess whether patients with RA and a history of co-morbid COPD treated with abatacept in a real-world, observational setting, have an increased risk of respiratory SAEs compared with similar patients treated with other biologic (b)DMARDs or the targeted synthetic DMARD tofacitinib (tofa). <h3>Methods</h3> The Truven MarketScan<sup>®</sup> Commercial and Supplemental Medicare databases were used to identify adult patients diagnosed with RA and COPD who were treated with abatacept, another bDMARD or tofa between <sup><sup>January 2007</sup></sup> and December 2015. Other bDMARDs included adalimumab, anakinra, certolizumab, etanercept, golimumab, infliximab, rituximab and tocilizumab. A prevalent new-user study cohort design<sup>2</sup> was used in which each new user of abatacept was time- and propensity score-matched to two new users of other bDMARDs or tofa. Patients were required to have ≥6 months of continuous health plan enrolment before cohort entry and were followed up until the end of enrolment in the database or 31 December 2015. Propensity scores of abatacept treatment were estimated from the baseline covariates using a conditional logistic regression model separately in incident new users and prevalent new users. Patients with score ranges common to both abatacept and the comparator cohorts were included. An as-treated analysis based on the Cox proportional hazard regression model was used to estimate the hazard ratios (HRs) of respiratory SAEs associated with abatacept compared with other bDMARDs or tofa, further adjusted for confounders found to be unbalanced despite matching on propensity scores. <h3>Results</h3> A total of 9746 patients with RA and COPD initiated bDMARD or tofa therapy and included 1807 new users of abatacept matched to 3547 new users of another bDMARD or tofa. The matched cohort was followed for up to 9 years (mean 2.0 years); 53% were incident users. For users of abatacept relative to other bDMARDs or tofa, the adjusted HRs (95% CI) of respiratory SAEs were: hospitalisation for COPD exacerbation: 0.57 (0.30, 1.05); hospitalisation for pneumonia/influenza: 1.39 (0.91, 2.12); outpatient pneumonia/influenza: 1.04 (0.85, 1.28) and outpatient bronchitis: 0.80 (0.57, 1.14). Results remained unchanged with sensitivity analyses. <h3>Conclusions</h3> In this real-world study of patients with RA and COPD, the incidence of pre-specified respiratory SAEs was not significantly increased in patients using abatacept compared with those using other bDMARDs or tofa. The safety signal based on the subgroup of 54 patients from the ASSURE trial could not be confirmed in this large and long-term cohort study of over 5000 patients. <h3>References</h3> [1] Weinblatt E, et al. Arthritis Rheum2006;54:2807–16. [2] Suissa A, et al. Pharmacoepidemiol Drug Saf2017;26:459–68. <h3>Disclosure of Interest</h3> S. Suissa Consultant for: Bristol-Myers Squibb, P. Ernst: None declared, S. Dell'Aniello: None declared, S. Shen Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb, T. A. Simon Shareholder of: Bristol-Myers Squibb, Employee of: Bristol-Myers Squibb