SAT0261 Abatacept is A Suitable Biologic Disease Modifying Anti-Rheumatic Drugs in Patients with Anti-Ss-A Antibodies-Positive Rheumatoid Arthritis
Authors: Y. Horai, A. Takatani, A. Nishino, Y. Nakashima, T. Suzuki, K. Fujikawa, T. Tsukada, M. Tsuboi, N. Matsuoka, K. Migita, T. Aramaki, Y. Ueki, S.-Y. Kawashiri, N. Iwamoto, K. Ichinose, M. Tamai, H. Nakamura, T. Origuchi, A. Kawakami
Journal: Annals of the Rheumatic Diseases (2014)

<h3>Background</h3> Recent report indicates that the presence of anti-SS-A antibodies are an independent factor associated with an insufficient response to tumour necrosis factor (TNF) inhibitors in patients with rheumatoid arthritis (RA) (Ref. 1). Since anti-SS-A antibodies are frequently found in patients with RA (20%), other classes of biologic disease modifying anti-rheumatic drugs (DMARDs) than TNF inhibitors may be indicative for active anti-SS-A antibodies-positive RA patients. <h3>Objectives</h3> To investigate whether abatacept (ABT) is effective for anti-SS-A antibodies-positive RA patients comparing with anti-SS-A antibodies-negative RA patients. <h3>Methods</h3> This is a prospective observational study and consists of 50 RA patients (42 females and 8 males) who had been administrated with ABT. Eighteen patients were anti-SS-A antibodies-positive whereas 32 were anti-SS-A antibodies-negative, respectively. Patients gave their informed consent to be subjected to the protocol. We have selected the anti-SS-A antibodies-negative RA patients whose baseline variables, including disease duration and clinical disease activity at baseline, were comparable with anti-SS-A antibodies-positive RA patients. The continuation rate and clinical disease activity including SDAI were evaluated during 6 months treatment of ABT. Statistical analysis included last observation carried forward (LOCF) method. <h3>Results</h3> At baseline, there was no statistical difference of SDAI in both groups: 20.47 in the anti-SS-A antibodies-positive RA group and 21.92 in the anti-SS-A antibodies-negative RA group, respectively (<i>p</i> =0.9554, Student9s <i>t</i> test). At 6 months, although there was no statistically significant difference between the 2 groups, SDAI tended to be lowered in the anti-SS-A antibodies-positive RA group as compared with anti-SS-A antibodies-negative RA group (9.11 in the former vs 12.11 in the latter, <i>p</i> =0.2036, Welch9s <i>t</i> test). It is interesting to note that the discontinuation rate for ABT due to lack of efficacy or adverse events at 6 months was significantly lower in anti-SS-A antibodies-positive RA group as compared with anti-SS-A antibodies-negative group (<i>p</i> =0.0475, Welch9s <i>t</i> test). <h3>Conclusions</h3> In comparison with TNF inhibitors, the present data suggest that ABT is a suitable biologic DMARDs in patients with anti-SS-A antibodies-positive RA. <h3>References</h3> Matsudaira R, Tamura N, Sekiya F, et al. Anti-Ro/SSA antibodies are an independent factor associated with an insufficient response to tumor necrosis factor inhibitors in patients with rheumatoid arthritis. J Rheumatol 2011; 38: 2346-54. <h3>Disclosure of Interest</h3> None declared <h3>DOI</h3> 10.1136/annrheumdis-2014-eular.3956