Goserelin Acetate

DescriptionGoserelin acetate, like leuprolide acetate, is a synthetic superagonist nonapeptide analogue of GnRH that possesses greater potency than the natural hormone. Note that it contains D-Ser(But) and NH-NHCONH2 in place of Gly6 and Gly10-NH2, respectively. That is, the C terminal modification simply has an NH substituting for the CH2 of Gly, and like the C-terminal change in leuprolide acetate, this inhibits enzymatic degradation of the peptide by the postproline carboxyamide peptidase. Goserelin acetate is available in the form of a small, solid pellet that is administered as an SC implant for the palliative treatment of advanced, metastatic breast cancer in pre- and perimenopausal women or, similarly, as a palliative in advanced prostatic cancer. The rationale for this drug's use is, as described above, its ability as a superagonist to bring the levels of estradiol or testosterone to near castrate levels, thus slowing the progression of breast or prostate carcinoma, respectively. Additionally, goserelin acetate is approved for use in treating endometriosis for up to 6 months.

DescriptionGoserelin is a synthetic gonadotropin-releasing hormone (GNRH) agonist that binds to the GNRH receptor (GNRHR; Ki = 1.6 nM, in CHO cells expressing the human receptor). It binds to mouse pituitary αT3-1 cells and human placenta (Kds = 2 and 580 nM, respectively) and increases intracellular calcium in αT3-1 cells. Goserelin induces testosterone production in vitro within 4 h in rat Leydig cells (ED50 = 83 nM) but decreases testosterone plasma level in vivo in rats over a period of 2 to 24 weeks. It inhibits tumor growth in a DU145 human prostate carcinoma mouse xenograft model when administered at a dose of 100 μg per day. Formulations containing goserelin have been used in the treatment of hormone-dependent breast and prostate cancers, as well as endometriosis and uterine fibroids.