Background:Anti-citrullinated proteins antibodies (ACPA) are a broad group of antibodies, including antibodies to citrullinated fibrinogen, antibodies to cyclic citrullinated peptide (anti-CCP), antibodies to modified citrullinated vimentin (anti-MCV), antibodies to citrullinated α-enolase.Objectives:To find a potential relationship between ACPA and disease activity, bone destruction, and ACPAs responses to various therapeutic regimens.Methods:The study included 232 patients (pts) with rheumatoid arthritis (RA); 90 pts (74 women, Me;IQR age 53.0 (38.0–58.5) years had early RA, with mean disease duration 5.0 (4.0–9.0) months, DAS 28 5.3 (4.4–6.1)); 142 pts had advanced stage of the disease (123 women, median age 51.0 (43.0–60.0) years, disease duration 56.0 (24.0–96.0) months, DAS 28 6.2 (5.5–6.8)). Pts with early RA received methotrexate (MTX) subcutaneously at average 17.5 mg dose once weekly. Pts with advanced RA received the following anti-B-cell therapy: 34 pts - rituximab (RTX); 20 pts - RTX biosimilar; 43 pts - tocilizumab (TCZ) in combination with conventional DMARDs. Serum anti-CCP and anti-MCV concentrations were measured using ELISA.Results:77 (85.6%) pts with early RA were high positive for anti-CCP, and 29 (70.7%) pts - high positive for anti-MCV. A positive correlation was found between anti-MCV and DAS 28 (r=0.4, p=0.04). As for advanced RA, 78 (80.4%) pts were high positive for anti-CCP, and 70 (79.5%) - for anti-MCV. There was a positive correlation between anti-MCV concentration and SDAI (r=0.4, p=0.02), as well as CDAI (r=0.4, p=0.02). No significant correlations were found between the anti-CCP levels and activity indices, anti-CCP and acute-phase parameters in both early and advanced RA groups. Higher total Sharp scores (96.5 (65.0-122.0)) were found in pts high positive for anti-MCV (n=79), compared to low-positive/negative (57.0 (31.0–88.0), respectively, (n=27, p<0.05). anti-MCV levels dropped significantly in pts on RTX and TCZ therapy at weeks 12 and 24 after initiation of treatment, while high anti-CCP concentration persisted throughout the treatment (Table 1)Conclusion:anti-MCV levels correlated with inflammatory activity and development of bone destruction, and were decreasing in pts on treatment. Anti-CCP was less responsive, showed minor changes during treatment, therefore its’ thorough monitoring was not feasible.Disclosure of Interests:None declared
POS0465 DIFFERENT CLINICAL RELEVANCE OF ANTI-CITRULLINATED PROTEINS ANTIBODIES IN RA PATIENTS
