indication

Degaralix is used for the management of advanced prostate cancer. Its action ultimately results in a reduction in circulating androgens, which provides a therapeutic benefit by reducing the growth stimulus used by hormone-sensitive malignant prostate tissue.

pharmacology

Degarelix is a synthetic derivative of GnRH decapeptide which normally stimulates the GnRH receptor. Gonadotropin and androgen production result from the binding of endogenous GnRH to the GnRH receptor. The ability of Degarelix to antagonize GnRH at its receptor and suppress the release of these hormones is what gives it potency in slowing advanced prostate cancer. Degarelix antagonizes the GnRH receptor which in turn blocks the release of LH and FSH from the pituitary. The reduction in LH leads to a decrease in testosterone release from the testes and subsequently reduces the size and growth of the prostate cancer.

mechanism of action

GnRH antagonists compete with natural GnRH for binding to GnRH receptors in the pituitary gland. This reversible blinding blocks the release of LH and FSH from the pituitary. The reduction in LH subsequently leads to a rapid and sustained suppression of testosterone release from the testes and subsequently reduces the size and growth of the prostate cancer.

biotransformation

Degarelix is subject to peptide hydrolysis during its passage through the hepatobiliary system and is mainly excreted as peptide fragments in feces. Approximately 20-30% of a given dose of degarelix is renally eliminated, suggesting that approximately 70-80% is excreted via the hepatobiliary system.

absorption

Degarelix forms a depot at the site of injection after subcutaneous administration from which the drug slowly released into circulation. Peak plasma concentrations of degarelix generally occur within 2 days following subcutaneous administration of a single 240-mg dose at a concentration of 40 mg/mL.

half life

23-61 days