Pos0728 effectiveness and safety of a 26 week taper regimen of glucocorticoid in newly-diagnosed gca patients: a real life experience

Background The GiACTA [1] was the first trial comparing two standardized prednisone (PDN)-taper protocols (52 week and 26 week) in GCA. Sustained remission rate at week 52 was similar. Patients enrolled in the placebo group with a 26 week taper protocol experienced lower PDN cumulative dose but more flares than those enrolled in the 52 week one. Objectives To assess the effectiveness and safety of the 26 week taper regimen of glucocorticoids (GC) used in the GiACTA trial in a prospective cohort of treatment-naive, biopsy-proven GCA. Methods Patients with a new diagnosis of biopsy-proven GCA enrolled in the GC arm of the START project (molecular stratification of patients with GCA to tailor GC and tocilizumab therapy) were included [2] . All patients were treated with the 26 week taper regimen of GC used in the GiACTA trial. Disease assessment was performed at baseline and every 12 weeks. In case of disease relapse, GC was increased or restarted with or without adjunctive immunosuppressive treatment. PET/CT was performed in 18 patients at baseline. Large vessel involvement was defined by evidence of vascular FDG uptake ≥liver in at least one vascular district. CT angiography was performed after at least 52 weeks of follow-up in all patients and was compared with baseline CT of the PET scan. The diameter of the aorta was measured at 4 different levels. Aortic dilation was defined by a diameter >40 mm in the ascending aorta, ≥40 mm in the descending aorta and ≥30 mm in the abdominal aorta. Any change of ≥5mm on serial CT was considered significant progression of aortic damage. Remission was defined as the absence of any clinical symptoms attributable to GCA, including a normalization of the acute phase reactants. Relapse was defined as one or more of the following: recurrence of signs or symptoms of GCA or PMR; CRP values greater than 10 mg/L, or ESR values greater than 40 mm/h if these were considered by the investigator to be due to GCA. The definition of relapse included the necessity for intensification of treatment. The primary endpoint was the rate of relapse-free remission at week 52. Secondary endpoints were the rate of remission at the end of follow-up and the proportion of patients with new aortic dilation or worsened aortic damage. Results 22 patients were included between December 2018 and February 2022. The baseline characteristics are reported in the Table 1. At week 52, 10 patients (46%, 95% CI 24-68) were in relapse free-remission. After a median (IQR) follow-up of 27.5 (18.5-34) months, 7 patients (32%, 95% CI 14-55) remained in relapse-free remission. 18 patients with baseline PET/CT underwent CT angiography at the end of the follow-up. No patients had evidence of new aortic dilation, significant progression of aortic damage or large vessel stenosis. 15/22 patients (68.2%) had at least one relapse during follow-up. No patients developed visual or cerebrovascular manifestations during relapses. Mean (SD) prednisone cumulative dose was significantly lower in non-relapsing than in relapsing patients at week 52 and at the end of follow-up [3.7 (1.3) vs 4.8 (8.7) g, p=0.017, and 4.3 (2.6) vs 6.8 (1.7) g, p=0.014, respectively]. However, 19/22 (83.4%) patients had at least one GC-related adverse event. Conclusion A 26 week taper regimen of GC was effective and safe in inducing and maintaining remission in a sizeable proportion of newly diagnosed cranial GCA patients. If confirmed in larger trials, this faster taper regimen could allow sparing GC, and should be considered as initial treatment in all newly-diagnosed GCA patients, reserving immunosuppressive treatment only in relapsing patients. References [1]Stone JH et al. N Engl J Med. 2017;377:317-328 [2] https://www.foreum.org/projects.cfm?projectid=142 Table 1. Baseline characteristics of the population Study population (n=22) Age (years) 74.8 (7.3) Female 19 (86%) Cranial symptoms 21 (96%) Visual symptoms 9 (41%) Systemic symptoms 8 (36%) PMR 8 (36%) Halo sign at US 15 (68%) LVV at PET CT 10/18 (56%) Aortic dilation 3/18 (17%) Data are mean (SD) or n (%). Acknowledgements Foundation for Research in Rheumatology (FOREUM) for funding the project. Disclosure of Interests None Declared.