FRI0366 SUBSTANTIAL CHANGES IN BONE FORMATION REGULATORS BIOMARKERS IN EARLY AXIAL SPONDYLOARTHRITIS – ROLE OF TNF INHIBITORS

Abstract

Background The hallmark of advanced axial spondyloarthritis (SpA) is spine ankylosis, due to an excess of bone formation. Our hypothesis was that pathways of bone formation regulators changed over time and that their changes were related to inflammation or use of “anti-inflammatory” drugs (like non-steroidal anti-inflammatory drugs (NSAIDs) and/or Tumor Necrosis Factor inhibitors (TNFi). Objectives This prospective study aimed to describe the 5-year serum changes of bone formation regulators markers (sclerostin, bone morphogenetic protein 7 (BMP-7) and Dickkopf-1 (DKK-1)) in early axial SpA and to assess determinants of their changes. Methods The DESIR cohort is a prospective, multicentre French study of 708 patients (34 ± 9 years, 58% HLA B27 positive, BASDAI 45 ± 20) with early (> 3 months and Results Serum levels of each biomarkers at baseline, two and five years are reported in Table 1. Serum BMP-7 significantly increased over time, with a mean of 0.17 pg/mL per month (Figure 1A). Median relative change of BMP-7 at five years was 53.0% [IQR -31.6%, 286.8%]. Serum BMP-7 levels was undetectable in 337 patients (59.6%) at baseline, in 111 patients (48.0%) at two years and in 59 patients (20.2%) at five years. At baseline, serum sclerostin was significantly correlated with age (r = 0.28, p Conclusion Serum BMP-7 levels significantly increased over time with a rapid and substantial change. Serum sclerostin levels significantly increased over time but to a lesser degree than serum BMP-7. Serum BMP-7 changes were related to the use of TNFi. Acknowledgement This study was supported by a grant from the French Society of Rheumatology (SFR) Disclosure of Interests Elise Descamps: None declared, Anna Molto: None declared, Didier Borderie: None declared, Rik Lories Consultant for: Abbvie, Celgene, Eli-Lilly, Janssen, Merck, Novartis, Pfizer, UCB, Corinne Miceli Richard Grant/research support from: MSD, Pfizer, AbbVie, Biogen, UCB, Novartis, Consultant for: Abbvie, Novartis, BMS, Christian Roux Grant/research support from: Alexion, Amgen, UCB, Karine Briot Consultant for: Karine Briot has received consultancy honoraria and conference fees from UCB, Amgen, Lilly and MSD