IL6R and rheumatoid arthritis: However, in the present analysis of patients with moderate-to-severe RA, blockade of IL-6Rα with sarilumab significantly decreased the sRANKL/OPG ratio, which is often used to measure the magnitude of bone resorption [16] and has been shown to predict 5-year and 11-year joint damage in patients with early untreated RA [16, 36].