P199 Glucocorticoid taper success after one and two years treatment in the Imperial College Takayasu Arteritis Cohort

Abstract Background/Aims The large vessel vasculitis Takayasu arteritis (TA) is initially treated with high dose glucocorticoids (GC) (40-60mg/day), typically with a csDMARD to induce remission. Subsequently, GC doses are tapered to reduce adverse effects. Although current EULAR guidelines tentatively recommend a target GC dose of < 10mg/day after one year of treatment, data describing GC taper patterns in practice is limited. This study describes GC taper success at one and two years and explores associated baseline and follow-up parameters. Methods A retrospective analysis of the Imperial College Takayasu Arteritis Cohort (UK) was undertaken; 158 patients with median follow-up 8.4 [5-13.6] yrs. Patients with sufficient data and typical treatment initiation pattern were analysed, commencing either GC monotherapy or GC + csDMARD and no baseline immunosuppression. Primary outcome: GC < 10mg/day after one and two years of treatment. Secondary outcome: patients achieving the same without intensification (addition of a second DMARD or biologic agent). Evaluation of taper failure causes was supported by NIH disease activity scoring. Taper failure and taper success groups were compared for baseline parameters and treatment at 5 years. Data are median [IQR], comparisons non-parametric for continuous variables. Results Of 129 TA cases requiring treatment, 80 (62%) satisfied analysis criteria. Overall, 46 (57.5%) and 59 (73.7%) patients met the primary outcome at years one and two respectively. Of these, 43 (93.5%) and 46 (78%) did so without treatment intensification. Taper success was consistent over time, with 43 (94%) year one taper success cases maintaining status at year two. In most cases (90.5%), year two taper failure was due to inadequate treatment response as confirmed by disease activity scoring (Table). Baseline parameters were similar between groups, except ESR which was significantly lower in the taper success group. As expected, initial treatment with GC monotherapy tended to be lower in the taper success group. At year five, GC doses remained higher and biologic usage was greater in taper failure cases suggesting a more refractory disease course (Table). Conclusion The EULAR GC taper target was achieved in 57.5% of patients, increasing to 73.7% by two years. Clinical implementation of this target is practical and will aid in the reduction of cumulative GC exposure and identification of patients requiring treatment intensification. Disclosure R. Alapat: None. A. Porter: None. C. Pericleous: None. T.A. Youngstein: None. R. Maughan: None. J.C. Mason: None.