An antibody or antigen-binding fragment thereof, which binds human IL-6 receptor (hIL-6R) with a K D of 500 pM or less, as measured by surface plasmon resonance. In preferred embodiments, the antibody comprising a light chain variable region (LCVR) comprising SEQ ID NO: 13, 15 and 17 as respectively light chain CDR1, CDR2 and CDR3, and a heavy chain variable region (HCVR) comprising SEQ ID NO: 5, 7 and 9 as respectively heavy chain CDR1, CDR2 and CDR3.
