Endocrine & Hormonal

Terlipressin is a synthetic vasopressin analog and the first FDA-approved medication specifically for treating hepatorenal syndrome (HRS), receiving approval in September 2022. It acts as a prodrug that is converted to lysine vasopressin, selectively activating V1 receptors in splanchnic vascular smooth muscle to cause vasoconstriction, reduce portal pressure, and improve renal perfusion in cirrhotic patients. Beyond HRS, terlipressin has well-established efficacy in controlling acute esophageal variceal hemorrhage, with multiple meta-analyses demonstrating significant mortality reduction compared to placebo. While highly effective for reversing hepatorenal syndrome when combined with albumin (reversal rates up to 80%), careful patient selection is critical due to risks of serious respiratory failure, particularly in patients with advanced acute-on-chronic liver failure (ACLF) grade 3.

Triptorelin is a synthetic decapeptide gonadotropin-releasing hormone (GnRH) agonist analog that was developed at Tulane University in Andrew V. Schally's laboratory and patented in 1975. It received FDA approval in 1986 and appears on the WHO Model List of Essential Medicines. The drug operates through a characteristic biphasic mechanism: initially stimulating the release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from the anterior pituitary, followed by sustained receptor downregulation that suppresses gonadotropin secretion, resulting in chemical castration within 3-4 weeks of continuous administration. This reversible suppression of the hypothalamus-pituitary-gonadal (HPG) axis makes triptorelin a first-line treatment for advanced prostate cancer, central precocious puberty, endometriosis, and uterine fibroids. It is also widely used in assisted reproductive technology to prevent premature ovulation during IVF cycles. Available in multiple sustained-release formulations (1-month, 3-month, and 6-month depot injections), triptorelin can be administered intramuscularly or subcutaneously. The medication is available by prescription globally and is marketed in over 80 countries for various hormone-dependent conditions.

Lysopressin (lypressin) is a synthetic analog of porcine antidiuretic hormone, differing from human arginine vasopressin by a single amino acid substitution (lysine instead of arginine at position 8). It was historically used as a nasal spray formulation (marketed as Diapid by Sandoz) for treating vasopressin-deficient diabetes insipidus from the 1960s through the 1980s. While effective at controlling polyuria through V2 receptor-mediated water reabsorption in the renal collecting ducts, lysopressin has been largely replaced by desmopressin (DDAVP) due to its shorter duration of action (3-4 hours) and requirement for more frequent dosing. Lysopressin is also the active metabolite of terlipressin, a prodrug used in managing hepatorenal syndrome and variceal bleeding in liver cirrhosis.

Anamorelin is a potent, selective, orally-active ghrelin receptor agonist developed for the treatment of cancer anorexia-cachexia syndrome (CACS). It mimics the N-terminal active core of endogenous ghrelin with high receptor affinity (0.70 nM) and has a longer half-life (approximately 7 hours) compared to natural ghrelin. Anamorelin was approved in Japan in December 2020 for treating cachexia in patients with non-small cell lung cancer, gastric cancer, pancreatic cancer, and colorectal cancer under the brand name Adlumiz, but has not been approved by the FDA or European regulatory authorities due to insufficient evidence of functional improvements despite increases in lean body mass.

Endoluten is a peptide bioregulator complex derived from pineal gland tissue, developed by Professor Vladimir Khavinson at the St. Petersburg Institute of Bioregulation and Gerontology. It contains short peptides (molecular weight <5000 Da) including the tetrapeptide AEDG (Ala-Glu-Asp-Gly), which regulates melatonin synthesis, circadian rhythms, and neuroendocrine function. Clinical and experimental studies demonstrate geroprotective effects including normalized hormonal function, improved cardiovascular and immune parameters, and significant mortality reduction in elderly populations over 6-8 year follow-up periods.