Arthritis Res Ther. 2015 May 20;17(1):135. [Epub ahead of print]Over the last decade, there has been a shift in treatment outcomes for RA; moving from symptom control to achieving remission. The TNF inhibitors have revolutionised treatment in this way, yet there is still a proportion of patients who fail to improve or reach remission. As such, new molecules for the treatment of RA are needed to be developed.This study investigates the in vitro and in vivo properties of ALX-0061, a bispecific Nanobody with a high affinity and potency for IL-6R.Positive pharmacological in vitro results were confirmed in non-human in vivo studies, supporting the clinical development of ALX-0061 in RA.