Persistence on anti-TNF therapy-data from Serbian National Spondyloarthritis Registry

Introduction/Objective The aim of our study was to retrospectively analyze data about efficacy and persistence on different anti-TNFa treatment in spondyloarthritis (SpA).Methods We retrospectively analyzed SpA patients whose data were entered into the Serbian national SpA registry. All patients were divided in two groups: non-switcher (patients who were treated with one anti-TNFa) and switcher group (who has switched from first to second and third anti-TNFa). Disease activity was measured by the Ankylosing Spondylitis Disease Score and the Bath Ankylosing Spondylitis Disease Activity Index and functional status was measured by the Bath Ankylosing Spondylitis Functional Index. Results We identified 290 SpA patients - 250 patients with axial SpA (axSpA) and 40 patients with pe-ripheral SpA (pSpA). Among 250 patients with axSpA, 192 (76.8%) did not change first anti-TNFa, while 58 (23.2%) switched to the second and 14 (5.6%) switched to the third anti-TNFa. Among 40 patients with pSpA, 29 (72.5%) did not change first anti-TNFa while 11 (27.5%) switched to the second and three (7.5%) switched to the third anti-TNFa. Survival on the first anti-TNFa was 35.16 +/- 28.5 months (switchers 29.41 +/- 21.89 vs. non-switchers 36.89 +/- 30.04). At the moment of this cross-section 37 (19.3%) patients still had very high disease activity, while only 75 (39%) patients had inactive disease.Conclusions In real-life clinical practice in our country, as well as in others, there is reluctance to anti-TNFa switch in SpA patients. Administrative limitations and national reimbursement policy could be one of the main reasons limiting treat to target implementation in SpA patients. Additionally, specific drug efficacy on extra-articular manifestations is often the reason for choosing the first line medication or switching to the next one.