Background According to Treat to target strategy, we have to consider changing the treatment in 3-6 months. Clinical course of RA treatment should be important to predict further outcome and to decide the therapy management in clinical practice.
Objectives We aimed to assess the efficacy of abatacept (ABT) in rheumatoid arthritis (RA) patients in switching and identify predictive factors at baseline for low disease activity (LDA) or remission using data from a multicenter registry, Tsurumai Biologics Communication Registry (TBCR).
Methods From 2,771 RA patients registered until 2013, 225 patients with moderate or high disease activity received ABT were selected [switching for biologics failure; n=100 and naive; n=125]. We compared clinical course and baseline characteristics between biologics-naïve and switching patients who achieved LDA. Predictive factors for LDA achievement were determined by multivariate logistic regression analysis in each group. The best cut-off of DAS28-CRP until 24 weeks for LDA achievement at 52 weeks was determined using Receiver operating characteristics (ROC) curve.
Results Baseline characteristics of study population (n=225) was mean age; 64.7yeras, disease duration; 11.5 years and baseline DAS28-CRP; 4.70, concomitant MTX use; 49.3% (mean dose; 7.3 mg/week). The biologics-naïve patients could achieve LDA at 52 weeks significantly more than in biologics-switching patients (56.0% vs 23.0%, p<0.001, Fig.1). Both naïve and switching patients who achieved LDA had no significant differences in background and improving to 12 weeks while the improving between 12-24weeks was less in bio-switching patients (Fig.2.). In biologics-switching patients, multivariate analysis revealed that baseline variables could not predict LDA achievement at 12 and 52 weeks at all, but DAS28-CRP at 12 weeks was an independent factor (OR: 0.20, p<0.001). DAS28-CRP at 0w-24w had significant association with LDA at 52 weeks in bio-naïve patients while DAS28-CRP at 0w in bio-switching patients did not (Fig.3). In bio-switching patients, the best cut-off of DAS28-CRP at 12w was 3.9 (sensitivity=0.83, specificity=0.81, positive predictive value: 0.56). In those patients with DAS28-CRP at 12w <3.9, the best cut-off of improving in DAS28-CRP from baseline to 12 weeks was 0.74 (sensitivity: 0.79, specificity: 0.60). We could predict LDA accurately (positive predictive value: 0.71) by these two indices in biologics switching patients.
Conclusions In switching to ABT, disease activity at 12weeks and clinical response up to 12 weeks were important information for prediction of long-term outcome.
Disclosure of Interest T. Kojima Grant/research support from: Takeda Pharma Corporation, Janssen Pharmaceutical, and Astellas Pharma Corporation., Speakers bureau: Mitsubishi Tanabe Pharma Corporation, Takeda Pharma Corporation, Eisai Pharma Corporation, Abbvie, Bristol-Myers Squibb, Pfizer, Chugai Pharma Corporation, Janssen Pharmaceutical, and Astellas Pharma Corporation, N. Takahashi: None declared, A. Kaneko Speakers bureau: Mitsubishi Tanabe Pharma, Takeda Pharma, Eisai Pharma, Chugai Pharma, Abbott, Bristol-Myers Squibb, UCB, Janssen, and Pfizer, D. Kida: None declared, Y. Hirano Speakers bureau: AbbVie Japan, Eisai, Mitsubishi Tanabe Pharma, Pfizer, Chugai Pharmaceutical, and Bristol-Myers Squibb, T. Fujibayashi: None declared, Y. Yabe: None declared, H. Takagi: None declared, T. Oguchi: None declared, H. Miyake: None declared, T. Kato: None declared, T. Watanabe: None declared, M. Hayashi: None declared, T. Shioura: None declared, Y. Kanayama: None declared, K. Funahashi: None declared, S. Asai: None declared, Y. Yoshioka: None declared, K. Terabe: None declared, T. Takemoto: None declared, N. Asai: None declared, N. Ishiguro Grant/research support from: Daiichi Sankyo, Takeda Pharmaceutical, Hisamitsu Pharmaceutical, Otsuka Pharmaceutical, Taisho Toyama Pharmaceutical, Kaken Pharmaceutical, Eisai, Janssen Pharmaceutical, Bristol-Myers Squibb, Abbott Japan, Chugai Pharmaceutical, Mitsubishi Tanabe Pharmaceutical, Astellas Pharma, and Pfizer Japan., Speakers bureau: Daiichi Sankyo, Takeda Pharmaceutical, Hisamitsu Pharmaceutical, Otsuka Pharmaceutical, Taisho Toyama Pharmaceutical, Kaken Pharmaceutical, Eisai, Janssen Pharmaceutical, Bristol-Myers Squibb, Abbott Japan, Chugai Pharmaceutical, Mitsubishi Tanabe Pharmaceutical, Astellas Pharma, and Pfizer Japan.