FRI0417 ETANERCEPT TREATMENT IN PATIENTS WITH NON-RADIOGRAPHIC AXIAL SPONDYLOARTHRITIS AND AN INADEQUATE RESPONSE TO NONSTEROIDAL ANTI-INFLAMMATORY DRUGS: PERIOD 1 RESULTS FROM THE RE-EMBARK TRIAL
Authors: Filip van den Bosch, James Cheng-Chung Wei, Peter Nash, Atul Deodhar, Francisco J. Blanco, Jack F. Bukowski, Ronald Pedersen, Bonnie Vlahos
Journal: Annals of the Rheumatic Diseases (2019)

<h3>Background</h3> Etanercept (ETN) is efficacious in patients with non-radiographic axial spondyloarthritis (nr-axSpA).<sup>1</sup> However, little is known<sup>2</sup> about the effect of ETN withdrawal in patients with nr-axSpA who achieved a significant clinical response. <h3>Objectives</h3> The primary objective of this ongoing, 3-period study is to estimate the proportion of patients with nr-axSpA who experienced a flare (Ankylosing Spondylitis Disease Activity Score with erythrocyte sedimentation rate [ASDAS-ESR] ≥2.1) within 40 weeks post-ETN withdrawal, after achieving inactive disease (ASDAS with C-reactive protein [ASDAS-CRP] &lt;1.3). Here, we report results of the 24-week Period 1, whose goal was to generate a population of ETN-treated patients with inactive disease. <h3>Methods</h3> RE-EMBARK (NCT02509026) is a multicenter, open-label trial in 18-50-year-old patients with active nr-axSpA (defined as fulfillment of Assessment in Spondyloarthritis International Society [ASAS] criteria, but not modified New York criteria, plus ASDAS-CRP ≥2.1), with an inadequate response to ≥2 nonsteroidal anti-inflammatory drugs (NSAIDs), who were on a stable NSAID dose for ≥2 weeks. In Period 1, all patients received ETN (50 mg/week) plus NSAID for 24 weeks. At week 24, patients who achieved inactive disease qualified for Period 2 and were withdrawn from ETN treatment for 40 weeks. In Period 3, patients who experience a flare during Period 2 will be retreated with ETN for 12 weeks. Efficacy outcomes for Period 1 included the proportions of patients achieving inactive disease and 20% and 40% improvements in ASAS disease activity (ASAS20 and ASAS40), as well as the changes from baseline in the Spondyloarthritis Research Consortium of Canada (SPARCC) scores for the sacroiliac joint (SPARCC-SIJ) and the spine (SPARCC-Spine). Efficacy analyses presented here were performed on the observed cases. <h3>Results</h3> Of 209 treated patients, 112 (54%) were men, 186 (89%) white, 142 (68%) had MRI-evident sacroiliitis, and 162 (78%) were HLA-B27-positive. The mean baseline score for ASDAS-CRP was 3.5, 8.5 for SPARCC-SIJ, and 2.7 for SPARCC-Spine. Twenty-one (10%) patients discontinued the trial. A significant decrease in ASDAS-CRP score was observed at all post-baseline visits (Panel A). At Week 24, 62% (117/188) of patients achieved inactive disease (Panel B), 86% (163/190) and 76% (144/190) achieved ASAS20 and ASAS40, respectively, and there was a significant reduction from baseline in SPARCC-SIJ (-5.8; <i>P</i>&lt;0.001) and SPARCC-Spine (-1.5; <i>P</i>=0.002). Seventy-nine (38%) patients experienced TEAEs, and 1 (0.5%) patient experienced a serious TEAE (cellulitis). <h3>Conclusion</h3> Majority of patients with active nr-axSpA and an inadequate response to NSAIDs achieved inactive disease and reduction of inflammation in both the SIJ and the spine with 24-week open-label ETN treatment. There were no unexpected safety signals. <h3>References</h3> [1] Dougados Met al, Arthritis &amp; Rheumatology. 2014;66:2091-2102. 2. Song IH et al, Ann Rheum Dis. 2012;71:1212-1215. <h3>Acknowledgement</h3> Medical writing assistance was provided by Vojislav Pejović of Engage Scientific Services and was funded by Pfizer. <h3>Disclosure of Interests</h3> Filip van den Bosch Consultant for: AbbVie, BMS, Galapagos, Janssen, Lilly, Merck, Novartis, Pfizer and UCB, Speakers bureau: AbbVie, BMS, Janssen, Lilly, Merck, Novartis, Pfizer and UCB., James Cheng-Chung Wei Grant/research support from: Abbvie, BMS, Celgene, Janssen, Novartis, Pfizer, and UCB pharma, Consultant for: TSH Taiwan, Speakers bureau: Janssen, Novartis, Pfizer and TSH, Peter Nash Grant/research support from: AbbVie, Bristol-Myers Squibb, Eli Lilly, Janssen, Novartis, Pfizer Inc, Roche, Sanofi, UCB, Consultant for: AbbVie, Bristol-Myers Squibb, Eli Lilly, Janssen, Novartis, Pfizer Inc, Roche, Sanofi, UCB, Speakers bureau: AbbVie, Bristol-Myers Squibb, Eli Lilly, Janssen, Novartis, Pfizer Inc, Roche, Sanofi, UCB, Atul Deodhar Grant/research support from: AbbVie, Amgen, Eli Lilly, GSK, Janssen, Novartis, Pfizer, and UCB, Consultant for: AbbVie, Amgen, BMS, Eli Lilly, Janssen, Novartis, Pfizer, and UCB, Francisco J. Blanco Consultant for: AbbVie, Bioiberica, BMS, GSK, Grünenthal, Janssen, Lilly, Pfizer, Regeneron, Roche, Sanofi, TRB Chemedica, and UCB, Jack F. Bukowski Shareholder of: Pfizer, Employee of: Former employee of Pfizer, Ronald Pedersen Shareholder of: Pfizer, Employee of: Pfizer, Bonnie Vlahos Shareholder of: Pfizer, Employee of: Pfizer