What the label states, the lot delivers — net peptide mass, not gross powder weight, purity reported as measured rather than rounded up, and a Certificate of Analysis for every lot.
Net peptide mass, not powder weight; purity as measured, not rounded up; a COA per lot.
Net peptide + purity not rounded up. COA per lot.
FDA PCAC reviews 7 peptides for the 503A bulks list (BPC-157, KPV, TB-500, MOTs-C, Emideltide, Semax, Epitalon). Read our compounder's decision tree. Read our briefing →
FDA PCAC reviews 7 peptides for the 503A bulks list in July. Read →
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Melanocortin-4 receptor agonist · approved for HSDD
Overview
PT-141 (bremelanotide) is an FDA-approved synthetic cyclic heptapeptide melanocortin receptor agonist that targets MC3R/MC4R in the central nervous system; structurally it is a cyclized analog of the alpha-melanocyte-stimulating hormone (4-10) fragment. Unlike traditional erectile dysfunction drugs that act through peripheral vascular mechanisms, PT-141 is thought to influence sexual arousal primarily through central nervous pathways, with effects observed in early clinical studies in both men and women. Under the brand name Vyleesi, it received FDA approval in June 2019 for acquired, generalized hypoactive sexual desire disorder (HSDD) in premenopausal women; a male indication has not been approved. Vialdyne releases PT-141 as a lyophilized heptapeptide (cyclic, lactam-bridged) against a ≥ 99.0% HPLC main-peak specification, with a batch-specific Certificate of Analysis covering RP-HPLC purity, mass-spec identity, water content, residual solvents, and endotoxin. Sequence / identity confirmation is documented on the released lot.
Applications & buyer fit
Cosmetic-peptide buyers fall into two groups: established beauty / med-aesthetic brands extending an existing line, and OEM clients building a private-label catalog from scratch. The first group usually wants active material plus stability data in their existing carrier matrix; the second usually wants a finished formulation under their label. Both need INCI naming verified, regulator-specific safety files (CPNP for EU, FDA OTC monograph for US where relevant), and packaging-compatibility data.
Sourced for
Buyer fit
Documentation that ships
Procurement note: INCI naming, SDS, and stability data in the chosen carrier ship with the active; finished-product safety remains the brand owner's responsibility.
Primary buyer fit: academic and contract research laboratories.
Specifications
Regulatory note
Research-use-only reference material; not for human or veterinary use.
Selected literature
Frequently asked questions
A qualifying record for the cyclic heptapeptide bremelanotide should carry an RP-HPLC purity result against a stated acceptance limit, a mass confirmation consistent with the declared structure, and a sequence or structural assignment rather than the trade name alone. Because it is a cyclic peptide, the documentation should reflect the intended ring form. Look for salt form, water content, net-peptide assay basis, and appearance of the lyophilizate. Endotoxin data supports preparations intended for injectable research use. Record lot, assay basis, and re-test date, and confirm net-peptide content so reconstitution to a target concentration is calculated correctly.
Reconstitute the lyophilized heptapeptide in sterile water for injection or isotonic saline, calculating concentration from the net-peptide assay figure rather than gross fill weight so the delivered amount matches intent. Given that research use is on-demand subcutaneous, prepare volumes that map cleanly to the intended per-administration amount. Split the reconstituted solution into single-use aliquots, hold frozen, and protect from light, since freeze-thaw cycling is the main in-lab degradation route for short peptides. Document vehicle, target concentration, and hold conditions per batch, and keep the material distinct from Melanotan II stocks to prevent identity mix-ups.
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