AB0515 Influences of Disease Activity at the Initiation of Iguratimod, a Small Molecule Antirheumatic Drug, on Efficacy of Iguratimod in Patients with Rheumatoid Arthritis – 52 Weeks Results from a Multicenter Registry Study TBCR
Authors: Y. Hirano, Y. Kanayama, H. Kanda, K. Saito, S. Hirabara, N. Takahashi, T. Ito, A. Kaneko, T. Kojima, N. Ishiguro
Journal: Annals of the Rheumatic Diseases (2015)

<h3>Background</h3> Iguratimod (IGU), known as T-614, is a small-molecule antirheumatic drug developed in Japan and used in Japanese clinical practice since June in 2012. IGU is one of the conventional synthetic DMARDs (csDMARDs). IGU is known to inhibit nuclear factor-kappa B activation in cultured human synovial cells and decrease IgG levels by acting B lymphocytes in both mices and humans. Although biological agents (BIO) have good efficacy to treat rheumatoid arthritis (RA), they costs very much. IGU is not comparatively expensive and shown to be effective as monotherapy <sup>1)</sup> or combination therapy with methotrexate (MTX) <sup>2)</sup> in patients with RA. Data in clinical practice is lacking and necessary for the best use of IGU. <h3>Objectives</h3> This retrospective observational study investigated 52 weeks efficacy of IGU in RA patients with focus on disease activity at initiation of IGU using data from the Japanese multicenter registry (Tsurumai Biologics Communication Registry plus: TBCR plus). <h3>Methods</h3> 65 cases (53 female and 12 male) with RA from 9 institutes in Japan were included. These patients were divided into two groups (high disease activity group; HG and moderate and low disease activity group; MLG) using DAS28-CRP at initiation of IGU. 38 cases were included in HG (DAS28-CRP&gt;4.1) and 27 cases were included in MLG (2.6&lt;DAS28-CRP4.1). Patients9 characteristics, time course of disease activity, drug retention rate until 52 weeks using Kaplan-Meier method and change value in disease activity parameters from 0w to 52w were compared with each other. <h3>Results</h3> Mean age was 69.2 years old in HG and 65.0 years old in MLG. Mean RA duration was 132.8 months in HG and 98.2 months in MLG. MTX use rate in HG was significantly low compared with that in MLG (39.5%/66.7%) (p=0.03). The mean dose of MTX used in HG and MLG at initiation of IGU was 4.7 mg/w and 5.2 mg/w, respectively. The difference was significant (P=0.02). Mean DAS28-CRPat 0, 4, 8, 12, 24 and 52w was 5.05, 4.40, 4.19, 3.80, 3.52 and 3.33 in HG and 3.26, 3.16, 2.80, 2.49, 2.43 and 2.52 in MLG. DAS28-CRP was significantly decreased in both groups. Similar findings were observed in SDAI. Drug retention rates at 52w were 71.1% in HG and 77.9% in MLG and there was not a significant difference between groups. Delta DAS28-CRP from 0w to 52w were1.73 in HG and 0.74 in MLG (p&lt;0.01). Delta SDAI were 13.8 in HG and 3.3 in MLG (p&lt;0.01). There were significant differences in delta tender joints counts, delta swollen joints counts between two groups and better improvement was seen in HG than MLG. <h3>Conclusions</h3> More treatment options other than sufficient MTX and BIO are needed in RA patients with concomitant disease such as lung disease or renal dysfunction. High cost of BIO is another issue to inhibit improvement of signs and symptoms in RA patients. This study suggests that IGU is one of the options in RA patients not only treated with sufficient MTX but also treated with insufficient MTX. <h3>References</h3> Hara M, et al. Mod Rheumatol. 2007; 17: 1-9. Ishiguro N, et al. Mod Rheumatol. 2013; 23: 430-439. <h3>Disclosure of Interest</h3> Y. Hirano Speakers bureau: Abbott Japan Co. Ltd.; Eisai Co. Ltd.; Mitsubishi Tanabe Pharma Corporation; Pfizer Co. Ltd.; Chugai Pharmaceutical Co. Ltd.; and Bristol-Myers Squibb Co. Ltd., Y. Kanayama: None declared, H. Kanda: None declared, K. Saito: None declared, S. Hirabara: None declared, N. Takahashi Speakers bureau: Abbott Japan Co. Ltd.; Eisai Co. Ltd.; Mitsubishi Tanabe Pharma Corporation; Pfizer Co. Ltd.; Chugai Pharmaceutical Co. Ltd.; and Bristol-Myers Squibb Co. Ltd., T. Ito: None declared, A. Kaneko Speakers bureau: Abbott Japan Co. Ltd.; Eisai Co. Ltd.; Mitsubishi Tanabe Pharma Corporation; Pfizer Co. Ltd.; Chugai Pharmaceutical Co. Ltd.; and Bristol-Myers Squibb Co. Ltd., T. Kojima Speakers bureau: Abbott Japan Co. Ltd.; Eisai Co. Ltd.; Mitsubishi Tanabe Pharma Corporation; Pfizer Co. Ltd.; Chugai Pharmaceutical Co. Ltd.; and Bristol-Myers Squibb Co. Ltd., N. Ishiguro Speakers bureau: Abbott Japan Co. Ltd.; Eisai Co. Ltd.; Mitsubishi Tanabe Pharma Corporation; Pfizer Co. Ltd.; Chugai Pharmaceutical Co. Ltd.; and Bristol-Myers Squibb Co. Ltd.