Introduction
Fertirelin acetate, classified into peptide hormone, is a gonadotropin-releasing hormone (GnRH) antagonist or analogue of luteinizing hormone releasing hormone (LH-RH), which is synthesized in the neurosecretory cells of the hypothalamus, and is released from the axonal end to the blood vessels of the first capillary plexus of the pituitary portal system when transported to the pituitary gland. It can directly act on the secretion of luteinizing hormone (LH) cells and promote LH release. Fertirelin acetate is a peptide which is developed for the treatment of prostate cancer and other diseases such as breast cancer and infertility.
Pharmacologic action
Testosterone promotes the growth of many prostate tumors, so lowering circulating testosterone to very low (castration) levels is often the treatment goal for males with advanced prostate cancer. Fertirelin can effectively block the pituitary gland from making hormones including FSH and LH. In male animals, this causes the testicles to stop making testosterone by directly inhibiting and secreting LH, which initially doesn't increase the level of testosterone to achieve the goal of prostate cancer. In addition, in women, this causes the ovaries to stop making estrogen and progesterone to cure the related diseases such as breast cancer and infertility.
Function
Owing to the special properties of fertirelin acetate, it can be used not only for the treatment of prostate cancer but also for amenorrhea caused by hypothalamic dysfunction, dysfunctional uterine bleeding, contraceptives, menstrual disorders caused by needles and other reasons of ovulation disorders. A study has shown that compared with the fenprostalene only treated in cows, the administration of fenprostalene following fetirelin treament is more effective in shortening the interval from treatment to conception in cows with follocular cysts. Another study has shown that the effective dose of fertirelin acetate is between 0.1 and 0.5 μg for superovulation induction in mice, that is to say, it also can be used in the treatment of sex hormone-dependent conditions and infertility in female.
Furthermore, treatment with an LH-RH agonist is called medical castration (sometimes called chemical castration) because it uses drugs to lower androgen levels in the body to the same extent as surgical castration (orchiectomy). But, unlike orchiectomy, the effects of drugs (such as fertirelin acetate) on androgen production are reversible. Once treatment is stopped, androgen production usually resumes.
Pharmacokinetics and metabolism
Fertirelin acetate is a peptide that has been used in veterinary medicine. Pharmacokinetic studies were conducted in mice, cows and ewe lambs. These studies showed that the fertirelin acetate has a good effect for treatment of prostate cancer and other diseases such as breast cancer and infertility.
References:
Nakao T, Harada A, Kimura M, Takagi H, Kaneko K, Sugiyama S, Saito A, Moriyoshi M and Kawata K. Effect of fenprostalene 14 days after fertirelin treatment on intervals from treatment to conception in cows with follicular cysts diagnosed by milk progesterone test. Journal of Veterinary Medical Science, 1993, 55(2): 207-210.
Nariai K, Ishinazaka T, Suzuki K, Uchiyama H, Sato K, Asano R, Tsumagari S, Yukawa M and Kanayama K. Optimum dose of LH-RH analogue fertirelin acetate for the induction of superovulation in mice. Experimental Animals, 2005, 54(1): 97-99.
Yildiz A. Effects of administration of fertirelin acetate and gentamycin sulphate after artificial Insemination on pregnancy rate of cows. Turkish Journal of Veterinary & Animal Sciences, 2014, 25(6): 1001-1006.
