A Multi-Biomarker Disease Activity (Mbda) Score Measures Rheumatoid Arthritis Disease Activity In Patients Treated With The Jak Inhibitor Tofacitinib

Background Quantitative assessment of disease activity is important for effective care of rheumatoid arthritis (RA). Treating to target levels of disease activity can improve patient outcomes, but composite indices are subject to inter-assessor variability and not universally adopted. In order to overcome this issue, a multi-biomarker disease activity (MBDA) blood test has been developed for RA disease activity that could complement clinical assessment and provide information about underlying disease processes. Recently, JAK inhibition has gathered attention as a novel therapeutic strategy for rheumatoid arthritis. Objectives To evaluate the MBDA test score as a measure of disease activity in patients treated with the JAK inhibitor tofacitinib. Methods MBDA was evaluated at baseline, 2 weeks, 3 months, 6 months and 1 year in 47 patients treated with a range of doses of tofacitinib. MBDA combines 12 serum biomarkers (VCAM-1, EGF, VEGF-A, IL-6, TNF-RI, MMP-1, MMP-3, YKL-40, Leptin, Resistin, CRP, SAA) in a pre-specified algorithm resulting in a score between 1 and 100. Association with clinical disease activity measures and change in these measures was assessed by Spearman correlation. 1. Primary endpoint: correlation of MBDA score with disease activity. 2. Secondary endpoint: correlation of MBDA score changes (ΔMBDA) with ΔDAS28 (ESR), ΔSDAI and ΔCDAI. Results Mean baseline characteristics were: age 55 years, duration 6.9 years, MBDA 60, DAS28 (ESR) 6.3, SDAI 37 and CDAI 34. MBDA scores were correlated with DAS28 (ESR), SDAI and CDAI (p Conclusions The MBDA score indicates both current disease activity and change in disease activity in patients treated with tofacitinib. Tofacitinib drives large decreases in the levels of disease activity biomarkers. Biomarker-based assessment of disease activity may complement tools such as CDAI, which include subjective assessments. These results suggest that MBDA may be a useful tool for objective disease activity assessment, requiring just a small amount of patient serum. Disclosure of Interest K. Yamaoka: None Declared, S. Kubo: None Declared, K. Sonomoto: None Declared, S. Hirata: None Declared, A. Voinov: None Declared, M. Rowe: None Declared, G. Cavet: None Declared, K. Saito: None Declared, Y. Tanaka Consultant for: Mitsubishi-Tanabe Pharma, Pfizer Inc., Speakers Bureau: Mitsubishi-Tanabe Pharma, Takeda Pharmaceutical Co Ltd, Abbott, Eisai Pharma, Chugai Pharm