CX3CL1 and rheumatoid arthritis: KANAb001 (E6011) is the first humanized anti-FKN mAb, generated by KAN Research Institute, Inc. Currently, phase 1/2 clinical studies of E6011 are ongoing in both RA and Crohn’s disease in Japan by Eisai Co., Ltd. Recently, we have reported that E6011 is safe and well tolerated and has a promising efficacy in active RA patients with MTX or TNF inhibitor-inadequate response (MTX-IR or TNFi-IR) at the American College of Rheumatology 2015.