Comparative overview of safety of the biologics in rheumatoid arthritis.

Six biologic agents are currently available in Canada for the treatment of rheumatoid arthritis (RA): abatacept, adalimumab, anakinra, etanercept, infliximab, and rituximab. Although they are generally considered to be safe and well tolerated, concerns have been raised regarding the use of biologic therapies in the treatment of RA. The new biologic agents abatacept and rituximab have novel mechanisms of action, and may therefore offer different safety profiles. The most important safety concerns with the biologic therapies remain the increased risk of infection. An increased risk of malignancies, including lymphoma and skin cancer, has been noted in RA trials, but the extent to which each of the biologic therapies contributes to the risk of malignancy has not been clearly defined.