In another study, the inhibitory effects of iguratimod alone or in combination with MTX on osteoprotegerin and RANKL were evaluated in RA patients for 12 and 24 weeks after treatment, clinically and in fibroblast-like synoviocyte cultures in vitro.52 All investigations revealed that iguratimod suppressed RANKL and osteoprotegerin expression, resulting in a reduced RANKL/OPG ratio. Here, TNFSF11 is linked to rheumatoid arthritis.