Anti-TNF therapy.

There are now five anti-tumour necrosis factor (TNF) drugs licenced for use in rheumatoid arthritis. This chapter examines the similarities and differences between the drugs and looks for clues with regard to their rational prescribing. The major difference is between the monoclonal antibody-based drugs and the soluble receptor etanercept. Etanercept exhibits the best drug survival and is also associated with a lower risk of opportunistic infections, particularly tuberculosis. Immunogenicity should explain some of the differences between the different drugs but the lack of standardised assays has hindered this area of research. The optimal approach to the patient who has failed their first anti-TNF remains unclear and awaits appropriate clinical trials. The safety profile of anti-TNFs has become clearer, largely through registry data. There is a small increase in serious and opportunistic infections but there does not appear to be a heightened cancer risk, and cardiovascular risk is probably reduced.