MMP9 and rheumatoid arthritis: In addition to suppressing the rheumatoid arthritis (RA)-modifying target TNF-α, the combination inhibits additional targets, including chemokine (C-C motif) ligand 5 (RANTES) and matrix metalloproteinase-9 (gelatinase-B), which are upregulated in RA synovium [27-30], and IL-6, which has been validated as a new target for the treatment of RA [31].