About the report : Rheumatic diseases, including rheumatoid arthritis, ankylosing spondylitis and psoriatic arthritis, constitute a significant part of the clinical picture in the population. Treatment with disease-modifying antirheumatic drugs (DMARD) may reduce or delay the progress of functional impairment and irreversible damage caused by the disease. However, there are many patients for whom these drugs do not have a satisfactory effect, especially after long term use. Treatment with TNF-inhibitors is an important option for these patients. In Norway, three types of TNF-inhibitors are approved for use in some rheumatic diseases: adalimumab, etanercept and infliximab, with the product names Humira, Enbrel and Remicade, respectively.
The aim of this report is to describe the evidence for use of TNF-inhibitors in the treatment of rheumatic diseases including rheumatoid arthritis, ankylosing spondylitis and psoriatic arthritis.
Method : Review of the scientific evidence based on systematic reviews and randomised controlled studies (RCTs).
Main findings : In the included studies, the three TNF-inhibitors adalimumab, etanercept and infliximab were found to be significantly more effective in reducing disease activity in rheumatoid arthritis, ankylosing spondylitis and psoriatic arthritis compared with control (placebo or other active treatments). The studies included in this report, were of short duration and therefore not suitable to evaluate long-term effects of TNF-inhibitors. Short observation periods and few patients also make it impossible to detect rare but potentially serious side effects. This also relates to an increased risk of cancer as it often occurs after several years.