Observational Multicenter Study of Refractory and/or Relapsing Takayasu Arteritis START: Study of Refractory and/or Relapsing TAkayasu aRTeritis

Takayasu arteritis (TA) is a vasculitis of unknown origin, resulting in progressive thickening and stenosis of large and medium arteries (the aorta and its major branches, and the pulmonary arteries). First line therapy of TA consists of high dose corticosteroids (CS) (Mukhtyar et al, 2009). Between 20 and 50% of cases respond to CS alone, with subsequent resolution of symptoms and stabilization of vascular abnormalities (Shelhamer et al, 1985; Maksimowicz-McKinnon et al, 2007). Although second-line agents (methotrexate, azathioprine, mycophenolate mofetil, cyclophosphamide) may result in initial remission, relapses remain common when prednisone is tapered (Maksimowicz-McKinnon et al, 2007). Thus, 50% of CS-resistant or relapsing TA patients may achieve sustained remission with the addition of methotrexate (Hoffman et al, 1994). During the last decade, biologics such as anti-tumor necrosis factor alpha (anti-TNFα) and anti-interleukin-6 (anti-IL-6) have been used as third-line treatment in refractory or relapsing TA. Almost 90% of CS-methotrexate resistant TA cases responded to infliximab, an anti-TNFα, and sustained remission was obtained in 37 to 76% of the cases (Schmidt et al, 2012; Comarmond et al, 2012; Mekinian et al, 2012). Tocilizumab, an anti-IL-6 has given similar results with 68% of sustained remission in refractory TA (Abisror et al, 2013). Irrespective of classical cardiovascular risk factors, the systemic inflammation and CS use play a pivotal role in the occurrence of cardiovascular thrombotic events (CVEs) (Roubille et al, 2015). As CVEs overlap with TA complications it is primordial to drastically taper CS in that vasculitis. We therefore aim to analyses prospectively the long term outcome of refractory/relapsing TA patients.