BARICITINIB FOR THE TREATMENT OF REFRACTORY VASCULAR BEHÇET’S DISEASE: A PILOT STUDY IN CHINA

Z. Wang, X. Wang, J. Liu, L. Zhang, W. ZhengPeking Union Medical College Hospital, Department of Rheumatology and Clinical Immunology, Beijing, China  Background Major vessel involvement in Behçet’s Disease (BD) profoundly affects morbidity and mortality. Monoclonal anti-TNF antibodies are recommended for severe and (or) refractory vascular BD (VBD) beyond glucocorticoids (GCs) and immunosuppressants (IS), while some patients are still struggling due to inadequate response and relative contraindications. Our group has previously reported the efficacy of JAK1/JAK3 inhibitor tofacitinib for treating VBD[1]. We hypothesized that the JAK1/JAK2 inhibitor baricitinib might be a potential therapeutic choice in VBD patients through a broader panel of cytokine inhibition. Objectives This is a single-center, one-arm, self-controlled, open-label pilot study aimed at evaluating the effectiveness and safety of the JAK1/JAK2 inhibitor baricitinib in BD patients with refractory vascular involvement. Methods We consecutively enrolled refractory VBD patients who received baricitinib treatment (2 mg/ day) at Peking Union Medical College Hospital between Mar 2020 and Jan 2022. Efficacy assessment mainly depends on the proportion of clinical remission after 3-month treatment. Other outcomes include disease activity, organ damage evaluation, GCs and IS-sparing effects, and side effects. Results A total of 17 patients (12 males) were included, with a mean age of 37.9 ± 11.9 years and a mean follow-up of 10.5±5.4 months (Table 1). Before enrollment, all patients had insufficient response or intolerance to conventional therapies and (or) biologics (five patients failed first-line anti-TNF mAb using infliximab/ adalimumab/golimumab, and two patients had second-line therapy with other anti-TNF mAb, but still responded inadequately). At the 3-month follow-up, 13 (76.5%) patients achieved a complete response and the proportion increased to 88.2% (15/17) at the last visit. Laboratory parameters ESR (13 (IQR 7–40.5) vs 8 (IQR 2–17.5) mm/h, p<0.01) and CRP (11.8 (IQR 2.5–18.5) vs 1.2 (IQR 0.6–5.2) mg/L, p<0.0001) decreased significantly 3 months after baricitinib use (Figure 1), as well as the Behçet’s Disease Current Activity Form (BDCAF) score (1 (IQR 0–2) vs 0 (IQR 0–1), p<0.01) and Birmingham Vasculitis Activity Score (BVAS) (2 (IQR 0–4.5) vs 2 (IQR 0–2), p<0.01). The vasculitis damage index (VDI) and Behçet’s Syndrome Overall Damage Index (BODI) remained stable (p>0.05). At the last visit, baricitinib showed a GCs-sparing effect (7.5 (IQR 5–11.3) vs 5 (IQR 3.1–10) mg/d, p<0.05), and 9 patients (52.9%) discontinued or maintained 5 mg or lower daily of GCs dosage. In addition, IS were reduced in number and dosage in 5 (29.4%) and 9 (52.9%) patients, respectively. During follow-up, baricitinib dosage was tapered to 1mg/day or less in 6 cases (35.3%) with sustained remission. No serious adverse events were noted during the follow-up. Conclusion Our study suggests that baricitinib is well tolerated and effective in refractory BD patients with multi-vessel involvement. Further prospective controlled study is warranted to access the utility of bariticinib in VBD. References Liu J, et al. A pilot study of tofacitinib for refractory Behçet’s syndrome. Ann Rheum Dis. 2020; 79:1517-1520. Image/graph:Figure 1. Outcomes of baricitinib treatment. Change in (a) ESR, (b) hsCRP, and (c) BDCAF score during follow-up. Table 1. Baseline demographic and clinical characteristics of enrolled patients. Characteristics VBD (n=17) Sex (male), n (%) 12 (70.6) Age at enrollment, mean ± SD (years) 37.9 ± 11.9 Duration of vascular involvement, median (IQR) (months) 29 (IQR 20.5-73.0) Follow-up, mean ± SD (months) 10.5 ± 5.4 Venous lesion, n (%) 5 (23.5)  Inferior vena cava syndrome 3 (17.6)  Deep venous thrombosis 3 (17.6)  Cerebral venous sinus thrombosis 2 (11.8) Artery lesion, n (%) 6 (35.3)  Multiple arterial occlusion/stenosis 3 (17.6)  Aneurysms/ pseudoaneurysm 4 (23.5) Pulmonary artery involvement, n (%) 1 (5.9)  Pulmonary thromboembolism 1 (5.9) Cardiac lesion, n (%) 8(47.1)  Valve regurgitation 7 (41.2)  Right heart thrombus 1 (5.9)  Coronary artery lesion 2 (11.8) Acknowledgements The authors thank all patients who participated in our study. Disclosure of Interests None Declared. Keywords: Targeted synthetic drugs, Vasculitis, Behcet’s disease DOI: 10.1136/annrheumdis-2023-eular.4785Citation: , volume 82, supplement 1, year 2023, page 1568Session: Vasculitis - large vessel vasculitis (Publication only)