Anti-TNF-alpha therapy with infliximab in spondyloarthritides

For patients with active ankylosing spondylitis (AS), medical therapy with TNF-blockers such as infliximab is increasingly considered the standard of care. This is especially true for patients who continue to have symptoms of active inflammation despite medication with nonsteroidal antiinflammatory drugs at the maximum possible dose. Insufficient control of disease activity as indicated by pain, stiffness and decrease of function is the most common clinical reason for starting anti-TNF therapy. The most recent follow-up data show that anti-TNF therapy with infliximab is clinically efficacious and safe, not only on a short- but also on a long-term basis in AS. Furthermore, there is evidence that infliximab also works in other spondyloarthritides (SpA) such as SpA associated with psoriasis, undifferentiated (early axial) SpA and in SpA associated with chronic inflammatory bowel diseases. Its benefit has even been reported in cases of reactive SpA. Withdrawal of long-term therapy in AS patients usually leads to flares and relapses after several weeks to months, but single cases of lasting remission have been reported. Only limited data are available regarding the optimal dosage of infliximab in SpA. In clinical practice, selected patients might not need doses of infliximab higher than 3 mg/kg but most patients will need doses of 5 mg/kg. A definite influence on radiographic progression after long-term continuous treatment with infliximab compared with conventional therapy has not been proven so far. This is in contrast to function and mobility, which even slightly improve over time in the patients who are still on therapy after 5 or more years (slightly over 50% of the initially treated patients in clinical trials). Antibody formation may lead to loss of efficacy (secondary nonresponse). Serious adverse events on anti-TNF therapy have remained rare as these can be largely prevented by appropriate screening. The large benefits of anti-TNF therapy in AS seem to outweigh the few shortcomings of this treatment.