Product introduction :

Gonadorelin is another name for gonadotropin-releasing hormone (GnRH). It is a synthetic decapeptide prepared using solid phase peptide synthesis. GnRH is responsible for the release of follicle stimulating hormone and leutinizing hormone from the anterior pitutitary.

Gonadorelin is responsible for the release of follicle stimulating hormone and leutinizing hormone from the anterior pitutitary. In the pituitary GnRH stimulates synthesis and release of FSH and LH, a process that is controlled by the frequency and amplitude of GnRH pulses, as well as the feedback of androgens and estrogens.

The pulsatility of GnRH secretion has been seen in all vertebrates, and it is necessary to ensure a correct reproductive function. Thus a single hormone, GnRH, controls a complex process of follicular growth, ovulation, and corpus luteum maintenance in the female, and spermatogenesis in the male. Its short half life requires infusion pumps for its clinical use.

GnRH is available as gonadorelin hydrochloride )and gonadorelin diacetate tetrahydrate for injectable use. Studies have described it being used via an infusion pump system to induce ovulation in patients with hypothalamic hypogonadism. It is also used in veterinary medicine as a treatment for cattle with cystic ovarian disease.

Goserelin is a synthetic analogue of a naturally occurring luteinizing-hormone releasing hormone (LHRH). Bioavailability is almost complete. Goserelin is poorly protein bound and has a serum elimination half-life of two to four hours in patients with normal renal function. The half-life increases with patients with impaired renal function. There is no significant change in pharmacokinetics in subjects with liver failure. After administration, peak serum concentrations are reached in about two hours. It rapidly binds to the LHRH receptor cells in the pituitary gland thus leading to an initial increase in production of luteinizing hormone and thus leading to an initial increase in the production of corresponding sex hormones. This initial flare may be treated by co-prescribing/co-administering an androgen receptor antagonist such as bicalutamide (Casodex). Eventually, after a period of about 14-21 days, production of LH is greatly reduced due to receptor downregulation, and sex hormones are generally reduced to castrate levels

Product Application:

Goserelin acetate is used to treat hormone-sensitive cancers of the breast(in pre- and peri-menopausal women) and prostate, and some benign gynaecological disorders (endometriosis, uterine fibroids and endometrial thinning). In addition, goserelin is used in assisted reproduction and in the treatment of precocious puberty. It may also be used in the treatment of male-to-female transgender people and is favoured above other anti-androgens in some countries, such as the UK. It is available as a 1-month depot and a long-acting 3-month depot.

Side Effects:

Goserelin acetate may cause a temporary increase in bone pain and symptoms of prostatic cancer during the first few weeks of treatment. This is known as the tumour flare effect, and is the result of an initial increase inluteinizing hormone production, before the receptors are desensitised and hormonal production is inhibited. The symptoms will disappear, with hormonal inhibition. It is therefore advisable to co-treat with anantiandrogen during the first 2-3 weeks of goserelin treatment, particularly in patients with pre-existing bone symptoms.