Axial spondyloarthritis is an inflammatory rheumatic disease causing back pain, functional impairment and potential ankylosis in the advanced stage. In this context, TNF blockers have been a major therapeutic advance. Etanercept is a soluble recombinant TNF receptor fusion protein in this vain. Areas covered: The aim of this review is to summarize the current published data concerning the efficacy and tolerance of etanercept in axial spondyloarthrits. The authors performed a systematic review on PubMed, using 'etanercept' and 'spondyloarthritis', 'axial spondyloarthritis' or 'ankylosing spondylitis' keywords. Expert opinion: Etanercept showed clinical efficacy on the axial (non-radiographic and radiographic) and peripheral manifestations (peripheral arthritis and enthesitis) of axial spondyloarthritis (Ax-SpA). Among the extra-articular manifestations, it works on psoriasis but not on inflammatory bowel disease, with a lack of efficacy data in anterior uveitis. Etanercept also demonstrated an interesting tolerance profile and good drug survival rates after 5 years. Etanercept was also shown to reduce MRI inflammation on the spine and the sacroiliac joints. However, like other TNF blockers, its impact on radiographic progression could not be fully demonstrated. In the context of upcoming new biologic targeted treatments, head-to-head and longer-term randomized controlled trials are now required to further define the role of etanercept in spondyloarthritis treatment strategies.
Keywords: Axial spondyloarthritis; Etanercept; MRI; TNF receptor; efficacy; outcome definition; radiographic progression; safety.