Safety of tumour necrosis factor and interleukin-1 blocking agents in rheumatic diseases

The three licensed TNFα blocking agents (etanercept, infliximab, adalimumab) and the recombinant form of human interleukin-1-receptor antagonist (anakinra) have all been shown to be effective in patients with chronic rheumatic autoimmune diseases; they have also been associated with certain types of serious adverse events. As expected, much of the information on serious events have accumulated during the post-marketing period. Certain serious, but uncommon, adverse events have been observed with all three TNFα blocking agents, including serious bacterial infections, tuberculosis (TB) and certain opportunistic infections, demyelinating syndromes, and lupus-like reactions. These data suggest that these adverse reactions may be related to blockade of TNFα and may therefore represent class effects of these agents. However, the severity and degree of risk may not be the same with all three agents. Blockade of interleukin-1 activity with anakinra appears, at present, to be relatively safe. The safety profile of these products will continue to be developed through the use of the registry, periodic safety updates from the passive surveillance program, and safety data from controlled trials of biological therapy for other diseases. Physicians should minimize risks by patient selection and screening for opportunistic infections. Moreover, the choice of the biological agent must be tailored to minimize risks and maximize benefits.