TNF and rheumatoid arthritis: In rheumatoid arthritis (RA) and Crohn's disease, concomitant use of methotrexate (MTX) during treatment with certain TNFα inhibitors (adalimumab, infliximab, and golimumab) has been demonstrated to decrease immunogenicity and significantly reduce clearance, resulting in higher systemic exposure and enhanced clinical efficacy [11, 14–18].