OBJECTIVES: To conduct a structured review of the literature to identify cost-effectiveness evaluations involving at least one of four biologic treatments: adalimumab, anakinra, etanercept and infliximab for the treatment of autoimmune disorders. METHODS: A structured review of the literature was conducted in EMBASE and PubMed from January 1995 to February 2005 to identify all relevant cost-effectiveness evaluations investigating one or more of these four treatments in autoimmune disorders. RESULTS: Fifteen full economic evaluations were identified. There were 12 for rheumatoid arthritis, 2 for Crohn's disease, and 1 for ankylosing spondylitis. There were 5 studies in the UK, 4 in the United States, 2 studies in Sweden, one joint study in Sweden and in the UK, one study in France, one study in The Netherlands and one study in Spain. The majority of evaluations used modeling to project the long-term cost-effectiveness of treatments. In general, cost-effectiveness ratios were favorable for the treatment of patients with refractory disease not responding to previous treatments whether in rheumatoid arthritis or ankylosing spondylitis. In Crohn's disease, biologic treatments were not cost-effective in the treatment of perianal fistulae, or for maintenance therapy in patients with moderate to severe active disease. Due to the high cost of these treatments, cost-effectiveness ratios were less favorable for maintenance therapy across diseases. CONCLUSION: Modeling the cost-effectiveness of more expensive biologic treatments in autoimmune disorders presents significant challenges due to the chronic and recurring nature of diseases such as rheumatoid arthritis, Crohn's disease and ankylosing spondylitis. A better understanding of these issues will be useful to researchers developing future models for these disease areas but also for other autoimmune disorders for which biologic agents may be appropriate such as, for example, ulcerative colitis, psoriasis and psoriatic arthritis.