Etanercept

Etanercept

Introduction

Etanercept is used to treat the autoimmune diseases and it interacts with the tumor necrosis factor by inhibiting it. The drug has been approved by United States Food and Drug administration department for the treatment of psoriatic arthiritis, ankylosing spondylitis, juvenile rheumatoid and rheumatoid (Feldmann & maini, 2003).

Drug absorption

The drug is administered subcutaneously by injection and it has found to be absorbing gradually from the site of injection. The drug reaches to its maximum concentration after 24 to 96 hours of administration. Several analytical studies have shown that the complete availability of the drug has found to be 76%. The steady state concentration of the drug turned out to be two to five folds greater after second dose. The average maximum concentration of serum after administration of first dose in healthy people has found to be 1.65 +- 0.66 mg/L. the saturation of clearance across the dose range was not found (Pfizer, 2013).

Distribution

The drug is released in the blood stream and then it is distributed into kidney, liver, heart, lungs and spleen. When the radiolabel form of the drug was administered subcutaneously or intravenously to mice, the radioactivity of the drug was observed in all the above mentioned organs of the body and the highest concentration was present in the blood. The drug cannot be transferred by milk or by placenta (EMEA, 2004).

Metabolism

The drug is a fusion protein that is formed by recombinant DNA. The drug fuses the receptor of the Tumor necrosis factor to the IgG1 antibody. The DNA sequence for soluble TNF receptor 2 was isolated first; TNF 2 receptor binds to the tumor necrosis factor-alpha. Furthermore, the DNA sequence for IgG1 was also isolated and then the DNA for IgG1 Fc was combined to the DNA for TNF receptor ...