The EXTEND trial was a double blind randomized placebo controlled study designed to test the effect of IL-6 receptor blockade (tocilizumab) in pediatric participants (age 6-17 years) with new onset type 1 diabetes. IL-6 pathway blockade is an effective immunotherapy in some autoimmune diseases including juvenile idiopathic arthritis and rheumatoid arthritis working, at least in part, by decreasing Th17 and increasing Treg cell frequencies. In a paper published in JCI Insight, the study team reported that while the drug impaired IL-6 signaling in T-cells, treatment did not alter T-cell subsets and did not slow the loss of the residual beta cell function in the study participants.
