Abstract
The introduction of biological therapy (bDMARD) into clinical practice is marked as major turning point in the approach to the treatment of rheumatic diseases. Data analysis from clinical practice and national registries of biological treatment showed that about a third of patients on therapy with bDMARD either not responding or there is a rapid failure of therapy effect associated with relapse of disease.
One explanation is imunogenicity of those protein based drugs , leading to the formation of antibodies against bDMARD called Anti-drug antibodies (ADA). Etanercept is a fusion protein consisting of the Fc region of human IgG domains azextracelul p75 for TNF has surprisingly low immunogenicity and the occurrence of ADA compared with other TNF inhibitors.