Background/Purpose : Serum MMP-3 is a specific inflammatory marker of the synovium in patients with rheumatoid arthritis (RA). Our aim in this study is to investigate whether serum MMP-3 is the predictor for remission in treatment for RA patients with biologics.

Methods: All RA patients (n=175) who underwent adalimumab (ADA) treatment in TBC (Tsurumai Biologics Communication) registry were enrolled in this study. We analyzed 107 patients in continuation with ADA therapy for 52 weeks. We divided into 2 groups based on the improvement of serum level of MMP-3 and CRP: high rate of improvement (MMP-HR group) and low rate of improvement (MMP-LR group) in serum MMP-3 levels at 4 weeks, and: high rate of improvement (CRP-HR group) and low rate of improvement (CRP-LR group) in serum CRP levels at 4 weeks. We also divided into 2 groups based on the serum level of MMP-3 and CRP: high value (MMP-H group) and low value (MMP-LR group) in serum MMP-3 levels at 4 weeks, and: high value (CRP-H group) and low value (CRP-L group) in serum CRP levels at 4 weeks (Table). We evaluated the rate of remission at 4, 12, 24, and 52 weeks in HR group and LR group.

Results: In patients continuing at 52 weeks, the rate of remission at 4, 12, 24 and 52 weeks in MMP-HR group is 41%, 37%, 56%, and 58%, and MMP-LR group is 14%, 19%, 26%, and 28% respectively. The rate of remission at 4, 12, 24 and 52 weeks in MMP-HR group is significantly higher than in MMP-LR group (Fig.1). However, the rate of remission at 24 and 52 weeks had no significance in CRP-HR group and CRP-LR group (Fig.2).The rate of remission at 4, 12, 24, and 52 weeks in MMP-H group is 9%, 18%, 26%, and 42%, and MMP-L group is 46%, 40%, 56%, and 45%. The rate of remission at 4 and 12 weeks in MMP-H group is significantly higher than in MMP-L group (Fig.3). However, the rate of remission at 4 weeks in CRP-H group is significantly higher than in CRP-L group (Fig.4). Moreover, the rate of remission at 24 and 52 weeks in MMP-(L and HR) group is very high (Fig.5). In patients continuing at 52 weeks, the best cut-off rate of improvement in MMP-3 at 4 weeks for determining remission at 52 weeks was 40% determined by ROC analysis (sensitivity: 60%, specificity: 80%, accuracy: 66%).

Conclusion: We considered that high rate of improvement in serum MMP-3 at 4 weeks can be useful for predicting the remission at 52 weeks in RA patients with ADA therapy.