TNFSF11 and rheumatoid arthritis: Moreover, upon further examination of osteoclasts derived from CD14+ monocytes isolated from active RA patients, in vitro application of IRL201805 appears to inhibit the receptor activator of nuclear factor-kB ligand (RANKL)-induced osteoclastogenesis and downregulate several vacuolar ATPases involved in the acidification of osteoclasts and bone resorption [40].