PT-141 (Bremelanotide) 10 mg Research Vial

What is PT-141?

This page covers PT-141 bremelanotide in a 10 mg research vial. PT-141 was the investigational code for bremelanotide, a synthetic cyclic heptapeptide. FDA labeling describes it as having an acetylated amino terminus and a free acid at the carboxyl terminus. The vial comes from PEPTYVA in Mexico, and Peptides Vallarta offers it for laboratory research use only. It is not Vyleesi and it is not a medicine.

How does bremelanotide act at melanocortin receptors?

Melanocortin receptors form a family of five subtypes, MC1R to MC5R. According to the Vyleesi label, bremelanotide is an agonist that activates several of them non-selectively, in this order of potency: MC1R, MC4R, MC3R, MC5R and MC2R. At the levels reached with the approved product, binding to MC1R and MC4R is the most relevant.

MC4R-expressing neurons are present in many areas of the central nervous system, and MC1R is expressed on melanocytes. The label states that the mechanism behind the approved indication is unknown.

What is the approved bremelanotide product?

FDA approved Vyleesi (bremelanotide) on 21 June 2019. Its labeled indication is "the treatment of premenopausal women with acquired, generalized hypoactive sexual desire disorder (HSDD)", as characterized by low sexual desire that causes marked distress or interpersonal difficulty and is not due to a co-existing medical or psychiatric condition, problems with the relationship, or the effects of a medication or drug substance.

The label, last revised in October 2026, states that Vyleesi is not indicated for HSDD in postmenopausal women or in men, and is not indicated to enhance sexual performance.

What did the phase 3 clinical trials study?

Two identical phase 3, randomized, double-blind, placebo-controlled clinical trials (RECONNECT, studies 301 and 302) randomized 1,267 premenopausal women with HSDD for 24 weeks. Both trials ran between January 2015 and August 2016; most participants were enrolled at US sites (96.6%), and their mean age was 39 years. The co-primary end points were changes in a desire score and in a distress score.

Nausea, flushing and headache were reported more often with bremelanotide than with placebo. The Vyleesi label lists warnings for a transient increase in blood pressure with a reduction in heart rate, focal hyperpigmentation, and nausea.

Why does the Vyleesi approval not cover this vial?

FDA approved a finished medicine: Vyleesi, with its own formulation, strength, container, labeling and approved population. This PEPTYVA 10 mg vial is a different product, sold as research material only.

The approval belongs to Vyleesi and does not extend to this research material. Grade A reflects the approval of bremelanotide inside Vyleesi; it says nothing about this vial.

How does PT-141 relate to MT-2?

Bremelanotide was developed as an analog of melanotan II (MT-2), and the two share the same cyclic seven-residue sequence. Bremelanotide ends in a free acid while melanotan II ends in an amide, giving the formulas C50H68N14O10 and C50H69N15O9. Melanotan II has no approved product, so its data and regulatory warnings should be read separately. See the MT-2 (melanotan II) 10 mg research peptide page.

Documentation

Your vial's PEPTYVA lot number identifies its batch. The Certificate of Analysis for that lot is available on request, before or after purchase; the Quality & Documentation page describes what a COA typically lists.

Storage and handling

Store the unopened vial sealed in its outer box, away from light and heat, at the temperature shown on the PEPTYVA label. The label and lot documentation give the storage conditions and expiry date for your lot.