FRI0008 Baseline Osteopontin Levels PREDICT the Clinical Efficacy of TOCILIZUMAB not Infliximab in Bio-Naive Rheumatoid Arthritis Patients: the Keio First BIO Cohort at 1 Year

Objectives To explore baseline predictive factors for clinical remissions at 1 year after tocilizumab (TCZ) or infliximab (IFX) treatment in bio-naive RA patients. Methods Consecutive bio-naive RA patients at our hospital initiating TCZ (n=70) or IFX (n=57) between February 2010 and April 2012 were included in this prospective cohort study with written informed consents. We assessed dichotomous or continuous variables at baseline for each biologic agent, including age, sex, disease duration, concomitant PSL dose, concomitant MTX dose, DMARD use, disease activity indices, HAQ-DI, the total Sharp/van der Heijde score (TSS), CRP, ESR and serum biomarkers levels (GM-CSF, IFN-γ, IL-1β, IL-2, IL-6, IL-8, IL-10, IL-12p70, IL-17, TNF-α, VEGF, sICAM-1, osteocalcin, osteonectin, osteopontin (OPN), BAP, MMP-3, IgM-RF, anti-CCP antibody (ACA)), to extract factors associated with remissions of SDAI (≤3.3) and CDAI (≤2.8) at 1 year using univariate analyses. The extracted variables, in conjunction with potential inter-linked factors (age, disease duration, IgM-RF, disease activity indices, and HAQ-DI), were subsequently applied to multiple regression analyses to identify independent variables to predict clinical remissions at 1 year. Serum levels of biomarkers were measured by ultra-sensitive electrochemiluminescence binding assay (except MMP-3, IgM-RF and ACA). Results At the beginning of the biologics, median (interquartile range) age in the TCZ and IFX group was 59 (48.8-64.5) years and 56 (47-67) years, respectively. The median disease duration at baseline in the TCZ and IFX group was 3.95 (1.5-7.9) years and 3.10 (0.5-13.7) years, respectively. Sixty-one and forty-seven females were included in the TCZ and IFX group, respectively. Median concomitant doses of PSL and MTX were 0 (0-3) mg/day and 8 (3-10) mg/week in the TCZ group, and 0 (0-0) mg/day and 8 (8-9.5) mg/week in the IFX group, respectively. Six patients used DMARDs other than MTX in each group. Median DAS28-CRP, SDAI and CDAI at baseline were 5.1 (4.2-5.9), 20.1 (15.2-28.0) and 19.0 (14.0-25.9) in the TCZ group, and 4.8 (3.8-6.1), 22.7 (14.8-39.8) and 20.1 (14.1-38.5) in the IFX group, respectively. There was no significant difference in these baseline characteristics between the groups. The DAS28-CRP ( 0.10, each). By univariate analyses, baseline OPN, TSS, ESR and age were selected as factors associated with SDAI and CDAI remission in the TCZ group, while baseline HAQ-DI and ACA were selected as those with SDAI remission and ACA with CDAI remission in the IFX group. By multivariate analyses, baseline OPN (OR 1.103, 95% CI 1.027-1.206, P=0.0059) and TSS (0.975, 0.953-0.991, 0.0042) were identified as independent predictors of SDAI remission, and baseline OPN (1.112, 1.035-1.208, 0.0130) and TSS (0.984, 0.969-0.996, 0.0130) as those of CDAI remission in the TCZ group, while baseline ACA was identified as that of SDAI and CDAI remissions. Conclusions Baseline serum OPN levels as well as TSS predict the SDAI and CDAI remission at 1 year after TCZ treatment, while baseline serum ACA levels predict that after IFX treatment in bio-naive RA patients. Disclosure of Interest K. Izumi: None declared, Y. Kaneko: None declared, M. Hashizume Employee of: Chugai Pharmaceutical Co., Ltd., N. Nishina: None declared, J. Kikuchi Consultant for: Pfizer Japan Inc., K. Yoshimoto: None declared, T. Takeuchi Speakers bureau: Abbott Japan Co; Abbvie GK; Asahi Kasei Pharma Corp; Astellas Pharma Inc; Astra-Zeneca KK; Bristol-Myers KK; Chugai Pharmaceutical Co, Ltd; Daiichi-Sankyo Co; Eisai Co; Eli-Lilly Japan KK; Janssen Pharmaceutical KK; Mitsubishi Tanabe Pharma Co; Novartis Pharma KK; Pfizer Japan Inc; Sanofi-aventis KK; Santen Pharmaceutical Co, Ltd; Taisho Toyama Pharmaceutical Co, Ltd; Takeda Pharmaceutical Co, Ltd; and Teijin Pharma Ltd DOI 10.1136/annrheumdis-2014-eular.2778