Triptorelin is a synthetic decapeptide agonist analog of luteinizing hormone releasing hormone (LHRH). It works by decreasing the production of certain hormones, which reduces testosterone levels in the body. Animal studies comparing triptorelin to native GnRH found that triptorelin had 13 fold higher releasing activity for luteinizing hormone, and 21-fold higher releasing activity for follicle-stimulating hormone. Triptorelin is indicated for the palliative treatment of advanced prostate cancer.

Abiraterone acetate (trade name Zytiga) is a prodrug to the abiraterone, steroidal compound with antiandrogen activity and a 17 α-hydroxylase/C17,20-lyase (CYP17) inhibitor. It is indicated in combination with prednisone for the treatment of patients with metastatic castration-resistant prostate cancer. Abiraterone acetate is converted in vivo to abiraterone which inhibits CYP17, enzyme expressed in testicular, adrenal, and prostatic tumor tissues and required for androgen biosynthesis. Administration of this agent may suppress testosterone production by both the testes and the adrenals to castrate-range levels. Androgen sensitive prostatic carcinoma responds to treatment that decreases androgen levels. Androgen deprivation therapies, such as treatment with GnRH agonists or orchiectomy, decrease androgen production in the testes but do not affect androgen production by the adrenals or in the tumor.

Ulipristal acetate (also known as CDB-2914 and PGL4001 and trade name Ella in the U.S) is a novel oral emergency contraceptive designed and developed by HRA Pharma. It is a selective progesterone receptor modulator, which reversibly blocks the progesterone receptors in target tissues it was approved in May 2009 by the European Commission and in August 2010 by the FDA as safe and effective in preventing unintended pregnancy for up to 120 hours – or five days – post- unprotected intercourse or contraceptive failure. Ella is not intended for routine use as a contraceptive. When taken immediately before ovulation is to occur, ella postpones follicular rupture. The likely primary mechanism of action of ulipristal acetate for emergency contraception is therefore inhibition or delay of ovulation; however, alterations to the endometrium that may affect implantation may also contribute to efficacy. The most common side effects are: headache, nausea, stomach (abdominal) pain, menstrual pain. Some women taking ella may have their next period earlier or later than expected. If your period is more than a week late, you should get a pregnancy test.

DEGARELIX (FIRMAGON®) is a synthetic linear decapeptide amide containing seven unnatural amino acids, five of which are D-amino acids. It is a GnRH receptor antagonist. It binds reversibly to the pituitary GnRH receptors, thereby reducing the release of gonadotropins and consequently testosterone. DEGARELIX (FIRMAGON®) is effective in achieving and maintaining testosterone suppression below the castration level of 50 ng/dL and is indicated for the treatment of patients with advanced prostate cancer.

Conivaptan is an arginine vasopressin (AVP) receptor antagonist with affinity for AVP receptor subtypes V1A and V2. The antidiuretic action of AVP is mediated through activation of the V2 receptor, which functions to regulate water and electrolyte balance at the level of the collecting ducts in the kidney. Conivaptan was approved in 2004 for hyponatremia caused by syndrome of inappropriate antidiuretic hormone. Conicaptan is being evaluated for reduce intracranial pressure in patients with traumatic brain injury, and as a treatment for heart failure.

Cetrorelix is a synthetic decapeptide with gonadotropin-releasing hormone (GnRH) antagonistic activity. GnRH induces the production and release of luteinizing hormone (LH) and follicle stimulating hormone (FSH) from the gonadotrophic cells of the anterior pituitary. Due to a positive estradiol (E2) feedback at midcycle, GnRH liberation is enhanced resulting in an LH-surge. This LH-surge induces the ovulation of the dominant follicle, resumption of oocyte meiosis and subsequently luteinization as indicated by rising progesterone levels. Cetrorelix competes with natural GnRH for binding to membrane receptors on pituitary cells and thus controls the release of LH and FSH in a dose-dependent manner. Cetrorelix binds to the gonadotropin releasing hormone receptor and acts as a potent inhibitor of gonadotropin secretion. It competes with natural GnRH for binding to membrane receptors on pituitary cells and thus controls the release of LH and FSH in a dose-dependent manner. Cetrorelix is marketed primarily under the brand name Cetrotide. Cetrotide (cetrorelix acetate for injection) is indicated for the inhibition of premature LH surges in women undergoing controlled ovarian stimulation.

Ganirelix (N-acetyl-3-(2-naphthyl)-D-alanyl-4-chloro-D-phenylalanyl-3-(3-pyridyl)-D-alanyl-L-seryl-L-tyrosyl-N9 ,N10-diethyl-D-homoarginyl-L-leucylN9 ,N10-diethyl-L-homoarginyl-L-prolyl-D-acrylamide) is a synthetic decapeptide with high antagonistic activity against naturally occurring gonadotropin-releasing hormone (GnRH). Ganirelix Acetate Injection is indicated for the inhibition of premature luteinizing hormone (LH) surges in women undergoing controlled ovarian hyperstimulation. Ganirelix is administered by a subcutaneous injection of 250 µg once per day during the mid to late follicular phase of a woman’s menstrual cycle. Treatment should start on the 5th or 6th day after the start of ovarian stimulation, and the mean duration of its use is five days. Clinical studies have shown that the most common side effect is a slight reaction at the site of injection in the form of redness, and sometimes swelling. Clinical studies have shown that, one hour after injection, the incidence of at least one moderate or severe local skin reaction per treatment cycle was 12% in 4 patients treated with Ganirelix and 25% in patients treated subcutaneously with a GnRH agonist. The local reactions generally disappear within 4 hours after administration. Other reported side effects are some that are known to be associated with ovarian hyperstimulation, including gynecological abdominal pain, headache, vaginal bleeding, nausea, and gastrointestinal abdominal pain.

Epelsiban (GSK557296), a pyridyl-2,5-diketopiperazine, is a potent, highly selective, and orally bioavailable non-peptide oxytocin receptor antagonist. GlaxoSmithKline was developing epelsiban for the treatment of women infertility due to adenomyosis and premature ejaculation.

Telapristone acetate, a selective progesterone receptor modulator (SPRM), was developed for the long-term treatment of symptoms associated with endometriosis and uterine fibroids. It is known, that the progesterone is a steroid hormone that plays an important role in the breast. Deregulation of the progesterone-signaling pathway is implicated in the formation, development, and progression of breast cancer. Thus, the telapristone acetate is studied in phase II clinical trial in stage I-II primary breast cancer. Besides, telapristone acetate participated in phase III clinical trials in pre-menopausal anemic women with symptomatic uterine fibroids. However, FDA terminated these studies because of the safety.

Inocoterone acetate (USAN) (also known as RU-38882, RU-882) is the acetate ester of inocoterone a steroid-like nonsteroidal antiandrogen (NSAA) that was developed for topical administration to treat acne but was never marketed. Inocoterone acetate is actually not a silent antagonist of the androgen receptor but rather a weak partial agonist, similarly to steroidal antiandrogens like cyproterone acetate. In this double-blind study of 126 male subjects with acne, a topical solution of the antiandrogen inocoterone produced a modest but statistically significant reduction in the number of inflammatory acne lesions.