Medicines of choice in managing inflammatory arthritis (RA and spondyloarthritis conditions) are the various disease-modifying anti-rheumatic drugs (DMARDs) which suppress and modulate the immune system. NSAIDs and glucocorticoids also have a role.
Conventional DMARDs (cDMARDs) include methotrexate, sulfasalazine, leflunomide and hydroxychloroquine. Biological DMARDs (or biologics) tend to be used if cDMARDs have been unsuccessful and include cytokine modulators which inhibit tumour necrosis factor alpha (TNF-α). Examples include adalimumab, certolizumab pegol, etanercept, golimumab, and infliximab.6,7,8
Each DMARD has its own mechanism of action, interfering at some point in the inflammatory pathways. cDMARDs such as methotrexate can act in a number of ways, so lack specificity.
Biologics, however, are highly selective. Their main modes of action are usually either to interfere with cytokine activity or production, to inhibit secondary messaging in T-cell activation, or to decrease B-cell activity.7
DMARDs can increase the risk and severity of infections as well as reactivating diseases such as tuberculosis, herpes zoster or hepatitis B or C.
Other serious adverse effects include bone-marrow suppression, promotion of lymphoma and non-melanoma skin cancers, increased congestive heart failure risk, and demyelinating diseases affecting the central nervous system.