Purpose of review: Biological agents are therapies designed to target a specific molecular component of the immune system, and are currently licensed for use in autoimmune rheumatic, digestive, dermatological and systemic diseases. However, their use has been linked with the paradoxical development of autoimmune processes.
Recent findings: More than 1500 cases of autoimmune diseases induced by biologics have been reported, including a wide variety of both systemic (lupus, vasculitis, sarcoidosis, antiphospholipid syndrome and inflammatory myopathies) and organ-specific (interstitial lung disease, uveitis, optic neuritis, peripheral neuropathies, multiple sclerosis, psoriasis, inflammatory bowel disease and autoimmune hepatitis) autoimmune processes. Although these processes are overwhelmingly associated with anti-TNF agents, recent cases have been associated with therapies directed against other cytokines, B or T-cells, illustrating that even though targeting a particular immune molecule may be associated with an excellent clinical response in most patients, an unexpected autoimmune response may arise in some cases.
Summary: As the use of biological therapies expands, the number and diversity of induced autoimmune disorders should be expected to increase. Paradoxically, for many of these drug-related processes, current treatment indications include the very biological agent producing the adverse event.