Background Matrix metalloproteinase-3 (MMP-3) is involved in disruptive events in the cartilage and bone of inflamed joints. In addition, serum MMP-3 is a specific inflammatory marker of the synovium, unlike C-reactive protein (CRP), which is a non-specific inflammatory marker, and is recognized to be correlated with disease activity in patients with rheumatoid arthritis (RA).
Objectives Our aim in this study was to investigate the relationship between serum MMP-3 and CRP which is associated with Boolean remission core measure sets in RA patients treated with adalimumab (ADA).
Methods All RA patients (n=175) who underwent ADA treatment between May 2008 and September 2009 at Nagoya University Hospital and 12 other institutes (Tsurumai Biologics Communication Study Group) were enrolled in this study. The serum MMP-3 and CRP levels of all patients at baseline were 331 ng/mL and 2.9 mg/dL, respectively. All patients were administered 40 mg ADA subcutaneously every 2 weeks. Correlations between serum MMP-3, as measured by the latex turbidimetric immunoassay (LTIA), and CRP levels were analyzed by the Pearson correlation-coefficient. Receiver-operated characteristic (ROC) analysis was performed to determine the cut-off MMP-3 value for CRP levels≤1, one of Boolean core measure sets.
Results We analyzed 107 patients in continuation with ADA therapy at 52 weeks and 14 patients in Boolean remission at 52 weeks. In both cases, significant correlations between serum MMP-3 and CRP levels were found at 0, 4, 12, 24, and 52 weeks. In patients continuing at 52 weeks, the best cut-off MMP-3 value for determining CRP levels≤1 at 4, 12, 24, and 52 weeks was 249 ng/mL, 135 ng/mL, 129 ng/mL, and 99 ng/mL, respectively. Its sensitivity (73%, 99%, 92%, and 88% respectively) and specificity (95%, 78%, 80%, and 75%, respectively) suggested that the cut-off MMP-3 values were preferable to determine CRP levels≤1 (Table). After the initiation of ADA therapy, serum MMP-3 and CRP levels decreased significantly. But unlike CRP levels, serum MMP-3 levels tended to decrease gradually until 52 weeks.
Conclusions In ADA therapy, serum MMP-3 can be useful for estimating the CRP levels≤1. We considered that serum MMP-3 can be the index of remission in RA patients with anti-TNFα therapy.
Disclosure of Interest Y. Hattori: None Declared, A. Kaneko: None Declared, T. Kojima Speakers Bureau: Abbott Japan, Chugai Pharmaceutical, Daiichi Sankyo Pharmaceutical, Eisai, Mitsubishi Tanabe Pharma, Pfizer Japan, Takeda, Y. Hirano: None Declared, T. Fujibayashi: None Declared, N. Takahashi: None Declared, K. Funahashi: None Declared, D. Kato: None Declared, H. Matsubara: None Declared, K. Terabe: None Declared, N. Ishiguro Speakers Bureau: Abbott Japan, Chugai Pharmaceutical, Daiichi Sankyo Pharmaceutical, Eisai, Mitsubishi Tanabe Pharma, Pfizer Japan, Takeda