PT-141 (Bremelanotide) is a highly potent synthetic peptide analogue of α-MSH that may elicit aphrodisiac effects through stimulation of melanocortin receptors. PT-141 (Bremelanotide) consists of seven amino acids and is a cyclic, shortened lactam variant of alpha-Melanocyte-stimulating hormone (α-MSH), a multifunctional peptide that regulates a broad array of physiological functions. In studies, bremelanotide was shown to induce lordosis in an animal model and was also effective in treating sexual dysfunction in both men (erectile dysfunction or impotence) and women (sexual arousal disorder).

PT-141 Basic Info.

Name: PT-141
Synonyms: Bremelanotide, PT-141 Acetate
CAS: 189691-06-3
Molecular Formula: C50H68N14O10
Molecular Mass: 1025.2 Da (g/mol)
Amino Acid Sequence: Ac-Nle-cyclo[Asp-His-D-Phe-Arg-Trp-Lys]-OH
Purity:PT-141 has a peptide purity level that exceeds 99.0% as determined by HPLC and MS. This peptide was synthesized with no additives and is supplied as a white lyophilized (freeze-dried) powder.

PT-141 Usage

Bremelanotide, similarly to its analogues α-MSH and melanotan II, acts as a non-selective agonist of all of the melanocortin receptors except MC2, where it lacks significant affinity. Reported activity of the drug is as follows:
MC1 (Ki = 0.68 nM)
MC2 (Ki > 1000 nM)
MC3 (Ki = 72.07 nM)
MC4 (Ki = 19.25 nM)
MC5 (Ki = 166.8 nM)

Bremelanotide appears to stimulate sexual desire and arousal completely or mostly via activation of the MC4 receptor (the MC3 receptor may also be involved). It modulates inflammation and limits ischemia via activation of the MC1 and MC4 receptors.

According to Palatin Technologies' original 2003 patent for bremelanotide, it possesses approximately 50 times the potency of melanotan II as an inducer of erection in male rats. In addition, it was stated in the patent that the therapeutic window of bremelanotide in animals (specifically, the range of induction of the desired sexual arousal relative to the induction of side effects including nausea, yawning, stretching, and decreased appetite) was >1,000-fold, whereas that of melanotan II was only 3- to 4-fold. They concluded that bremelanotide would be more tolerable than melanotan II.

PT-141 10mg (Bremelanotide 10mg)
PT-141 or Bremelanotide is the generic term for a research peptide being studied for its possible use in helping to improve sexual dysfunction in both men (erectile dysfunction or impotence) and women (sexual arousal disorder). PT-141 was developed from the tanning peptide Melanotan 2, which is a synthetically produced variant of a peptide hormone naturally produced in the body that stimulates melanogenesis that is known as alpha-Melanocyte stimulating hormone. MSH, activates certain melanocortin receptors in the process of exerting its effects. Indeed, MSH also exerts potent influence over lipid metabolism, appetite, and sexual libido. Resultantly, PT-141 has been shown in studies to exhibit libido-enhancing effects by activating the melanocortin receptors MC1R and MC4R, but not skin tanning. Melanotan 1 and Melanotan 2 have been researched for their use in protecting against the harmful effects of ultraviolet radiation from sunlight due to their melanogenesis-stimulating properties.

The Development of PT-141
PT-141 was developed from the Melanotan 2 Peptide, which underwent testing as a sunless tanning agent. In initial testing, Melanotan 2 did induce tanning, but additionally caused sexual arousal and spontaneous erections as unexpected side effects in nine out of the ten original male volunteer test subjects. Palatin completed patient treatment in its Phase 2B clinical trial in premenopausal women with FSD Primary data analysis and announcement of top-line results anticipated in first-half of fourth quarter of calendar year 2012. In studies, PT-141 was shown to be effective in treating sexual dysfunction in both men (erectile dysfunction or impotence) and women (sexual arousal disorder). Unlike other related medications, it does not act upon the vascular system, but directly increases sexual desire via the nervous system.