PT-141 (Bremelanotide) is a cyclic heptapeptide lactam analogue of α-MSH (α-melanocyte-stimulating hormone) with amino acid sequence Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-OH and average elimination half-life 2.7 hours. It is an active metabolite of Melanotan 2 peptide that lacks the C-terminal amide group, however, PT-141 does not significantly stimulate melanogenesis (increased pigment formation) unlike Melanotan 2.
This peptide mainly strongly increases and stimulates libido, sexual arousal and sexual activity in both, men and women. PT-141 can be used as the treatment of generalized hypoactive sexual desire disorder (HSDD), erectile dysfunction (ED) in men (even in men who have not responded to other erectile dysfunction treatments such as Viagra, Cialis etc.) and similar sexual arousal disorders. PT-141 (Bremelanotide) is officially approved for medical use in USA from year 2019.
PT-141 acts as non-selective agonist of the melanocortin receptors, primarily as agonist of melanocortin receptors 3 & 4 (MC3 & MC4) and with the exception of melanocortin receptors 2 (MC2 – the receptor of ACTH). Its bioavailability at subcutaneous injection is about 100%, maximal levels occur after about 1 hour, with a range of 0.5 to 1.0 hours and the plasma protein binding of PT-141 is approx 21%.
PT-141 (Bremelanotide) is metabolized via hydrolysis of its peptide bonds; its elimination half-life is about 2.7 hours (with a range of 1.9 to 4.0 hours), and is excreted from the body 64.8% in urine and 22.8% in feces. PT-141 (Bremelanotide) triggers sexual arousal in both men and women within a few minutes of administration, and has been shown its have significant results on male test patients in form of intense and frequent erections, lasting between 2-6 hours. It may also cause a temporary increase in blood pressure and decrease in heart rate after each dose.
