<h3>Background</h3> Therapeutic guidelines draw heavily on evidence from randomized controlled trials undertaken in well-characterized, highly-selective populations and managed in tightly-controlled settings. As such, the extent to which therapeutic efficacy in real-life populations and routine care settings is often unclear [1–2]. <h3>Objectives</h3> To assess subcutaneous (SC) abatacept (ABA) efficacy and safety in a real-life setting. <h3>Methods</h3> This was a retrospective and single center study in which 94 patients (1987 ACR) were assessed from April 2014 to January 2016. The patients were stratified according to their treatment background: (n=39) biologic-naïve, (n=22) switched from IV to SC ABA administration (125mg-wk), and (n=33) inadequate response to TNF inhibitor (TNF-IR). The primary and secondary endpoints were change in DAS28-CRP, and Routine Assessment of Patient Index Data (RAPID3) from baseline to 6 months, respectively. A linear mixed effects model was made to account for correlation among repeated measures. Adverse events (AEs) were assessed and recorded at each visit to the rheumatology center. <h3>Results</h3> Baseline characteristics of patients were as follows: female gender 86%, mean age 55.2±12.3 years, median disease duration 12.5 (IQR 14) years, Rheumatoid Factor positive 94%, Anti-Cyclic Citrullinated Peptide Antibodies 84%, mean DAS28-CRP 5.4±0.72, and mean RAPID3 15.6±5.0. SC ABA monotherapy, concomitant use of methotrexate (MTX), and leflunomide were reported in 10%, 48%, and 27%, respectively. Demographics and disease characteristics were similar in all groups, except for baseline DAS28-CRP (p<0.0001), and RAPID3 (p<0.0001) in switch group. After 6 months of administration, the DAS28-CRP score change was statistically significant irrespective of group. The scores changed from 5.4±0.9 to 3.8±1.3 (p<0.0001, biologic-naïve group), from 3.1±1.2 to 2.7±1.2 (p=0.002, switch IV-SC group), and from 4.6±1.9 to 3.2±1.4 (p=0.0305, TNF-IR group). The RAPID3 scores changed from 18.1±5.4 to 12.1±6.3 (p<0.0001, biologic-naïve group), from 10.4±6.6 to 9.2±7.0 (p=0.0114, switch IV-SC group), and from 16.1±5.7 to 11.8±7.1 (p=0.284, TNF-IR group). No patients relapsed or needed to return to the IV administration. Infections, headache, and constitutional symptoms, occurred in 48%, 37% and 32% of patients, respectively. Serious infections were reported only in 2% of patients (i.e., herpes zoster). Local injection-site reactions occurred in 13% of patients. Most of AEs reported were reversible and mild. There were no treatment discontinuations. No deaths and malignancies were reported. <h3>Conclusions</h3> Our results disclose an improvement in RA disease activity and physical function, during 6 months administration of SC ABA. Patients switching from IV to SC formulation of ABA had lower activity and functional impairment at baseline, and efficacy was maintained through follow-up. SC ABA demonstrated a good safety profile, consistent with previously published data. <h3>References</h3> Reggia R, et al. J Rheumatol 2015;42(2):193–5. Nüβlein H, et al. Arthritis Rheum 2012;64(Suppl10):S199. <h3>Disclosure of Interest</h3> None declared
