P146 Pragmatic Biologic Tapering Combining Clinical and Ultrasound Assessment in Patients with Rheumatoid Arthritis in Routine Clinical Practice - Predictors of Failure from a Regional Centre in UK

Abstract

Abstract Background/Aims Tapering biologic therapies in patients with rheumatoid arthritis (RA) is evolving. Our primary objective was to combine clinical and ultrasound assessment in selecting patients with RA for tapering biologic therapies. The secondary objectives were to identify predictors for failure and cost savings. Methods RA patients on biologics in sustained clinical remission (defined as DAS 28 < 2.6) in the previous year and imaging remission (defined as Power Doppler US of small joints of hands not significant) were included. The patients were seen in a multidisciplinary clinic with an advanced pharmacy practitioner between April 2019 and March 2022. They were advised to lengthen the interval of their biologics gradually and were followed quarterly till September 2022. Failure was defined as reverting to previous regime at any point during follow up. Independent predictors of failure were identified with Cox multiple regression analysis SPSS v29.0 (IBM 2022). Results Biologics were tapered in 184 patients including 129 on anti-cytokine therapy (abatacept 13, adalimumab 35, certolizumab 31, etanercept 18, golimumab 8, infliximab 4, tocilizumab 20) and 55 on rituximab. The mean age of the cohort was 63.8±11.7 years and there were 72.3% females. The mean duration of RA was 15.2 ± 7.9 years and baseline DAS28 before taper was 1.93±1.04 years. Concomitant DMARDs were used in 53.8%. Anti-cytokine therapy:Over 287.9 patient-years follow up (mean follow up duration: 26.8 ± 14.1 months), taper failure occurred in 36 (27.9%) patients in a mean time of 12.0 ± 8.1 months. There was no statistically significant difference in failure rate between different agents. A 50% dose reduction could be achieved in 65 (50.4%) patients with the mean time to achieve it of 10.4 ±9.1 months. Thirteen (10.1%) patients stopped biologics completely. Current smoking [HR:3.67 95%CI:1.50-9.00, p:0.04] and higher DAS28 at initiation of taper [HR:1.93 95%CI:1.11-3.36, p:0.020] were predictive of taper failure. All but 3 of the 36 patients who failed taper, responded on reverting to their previous treatment regime. Anti B-cell therapy:The 55 patients on Rituximab were tapered to a lower dose or had their interval lengthened. Over 98.6 patient-years follow up (mean follow up: 21.5 ± 11.3 months). Mean dose reduction achieved was 62.2 ± 19.9 %. Mean interval between RTX infusions was 12.9 ± 6.4 months. We have managed to save nearly £800,000 over the 3 years with tapering of biologics in this cohort of RA patients compared to the standard dose. Conclusion Successful tapering of biologic therapies in patients with rheumatoid arthritis is feasible and safe in majority of patients who are in clinical and imaging remission. Current smoking and baseline high DAS28 predicted taper failure for anti-cytokine biologics. This can be safely managed by reverting to the original dosing in most patients. Disclosure H. Muhammed VK: None. A. Yau: None. G. Hirsch: None. T. Sheeran: None. S. Venkatachalam: None.