PT-141 (Bremelanotide): Is It Legal, and Where Do You Buy It in 2026?

The Melanotan II connection

The relationship with Melanotan II is chemical, historical, and easy to compress into the wrong conclusion. Peer-reviewed literature describes PT-141 as the carboxylate derivative of MT-II, or Melanotan II. In practical naming terms, PT-141 descends from Melanotan II but is a distinct molecule.

That distinction resolves two common search questions at once. PT-141 is bremelanotide. PT-141 is not Melanotan II. Calling one a derivative of the other identifies parentage without making the names synonymous. It also keeps the evidence attached to each molecule separate, which matters when reading receptor studies, trial registries, and regulatory documents.

The two molecules differ by roughly one mass unit, which is why mass-spectrometry identity data matters more here than on a typical linear peptide. Chemical identity is only one documentation layer. The guide to matching a certificate of analysis to its physical lot explains how identity and batch records connect. A shared family history or research nickname cannot replace a lot-specific analytical record.

From development programme to approved product

The registration programme consisted of two Phase 3 RECONNECT studies. NCT02333071, sponsored by Palatin Technologies, enrolled 723 participants and ran from December 2014 to June 30, 2017. NCT02338960, also sponsored by Palatin Technologies, enrolled 714 participants and ran from January 2015 to June 29, 2017. Both studies concerned acquired, generalised hypoactive sexual desire disorder in premenopausal women.

The trials were reported together by Kingsberg and colleagues in "Bremelanotide for the Treatment of Hypoactive Sexual Desire Disorder: Two Randomized Phase 3 Trials," published in Obstetrics and Gynecology in 2019, volume 134, issue 5, pages 899 to 908. Their publication established a peer-reviewed account of the two trials without changing the scope later set by the approved label.

FDA approved Vyleesi on June 21, 2019 under NDA 210557. The approval letter is addressed to AMAG Pharmaceuticals, Inc., and identifies the indication as acquired, generalised hypoactive sexual desire disorder in premenopausal women. The general product-specific nature of drug approvals is covered in more depth in Curo's profile of tesamorelin and its approved product.

What the label actually covers

The most informative part of the Vyleesi label is its boundary language. The label says Vyleesi is not indicated for hypoactive sexual desire disorder in postmenopausal women or in men, and is not indicated to enhance sexual performance. It also lists uncontrolled hypertension and known cardiovascular disease as contraindications.

Those limitations are unusually explicit. The indication names a defined population and condition, while the exclusions close off three broader readings that the compound's general visibility might otherwise invite. The approved record does not turn PT-141 into a category-wide term for every melanocortin compound or every research setting.

Regulatory scope and analytical documentation remain distinct parts of a research record. Curo's quality and testing standard consists of exactly three methods: HPLC, LC-MS, and endotoxin testing. Those methods document characteristics of a specific lot. They do not reproduce the manufacturing, review, or application file of Vyleesi.

Where PT-141 research goes next

Bremelanotide remains in clinical development outside the approved indication. NCT06565611 is a Phase 2 study of bremelanotide combined with tirzepatide in obesity, sponsored by Palatin Technologies. It started on August 5, 2024 and is listed as active and not recruiting. The registry can be followed for later changes in study status, posted results, and publication references.

Compounding policy followed a different 2026 track. PT-141 was not among the substances reviewed at the July 23 and 24, 2026 Pharmacy Compounding Advisory Committee meeting. The meeting notice covered BPC-157, KPV, TB-500, MOTS-c, emideltide, semax, and epitalon.

For PT-141, the next useful evidence will come from clearly identified studies and updated primary records. Substance synonyms, parentage, an approved label, and an active Phase 2 programme already form a substantial record. Keeping those elements separate preserves the specificity that makes the compound notable.

Is PT-141 legal to buy?

In the United States, PT-141 sits on both sides of a line that most research peptides sit on only one side of. Bremelanotide is lawfully available by prescription as Vyleesi, within that product's approved label. Separately, raw PT-141 is sold as a research chemical for laboratory use. It is not a controlled substance and does not appear on any DEA schedule as of August 2026. Research-chemical PT-141 is not an approved drug, not a dietary supplement ingredient, and not cleared for human or veterinary use in any form.

Three boundaries define the current picture:

1. The approved route and the research market are separate. Vyleesi is a specific drug product with a specific label, made and reviewed under NDA 210557. A research vial of PT-141 is not that product, and no research supplier can inherit its regulatory status.
2. Research sale is lawful; human-use marketing is not. FDA has repeatedly cited peptide sellers whose sites promote human use. The owner of one vendor, Paradigm Peptides, was sentenced to 70 months in federal prison in July 2026 for selling unapproved and adulterated drugs. The offense was not stocking peptides. It was selling them for human consumption while faking the paperwork.
3. The compounding question was not opened for PT-141. The July 2026 advisory committee reviewed seven other peptides and did not take up bremelanotide. Nothing in that process changed its status either way.

Any supplier selling raw PT-141 sells it strictly for laboratory research, not for human or animal use. Curo's research use only policy covers what that means in practice for the compounds Curo lists.

Where to buy PT-141 for laboratory research

Researchers looking for where to buy PT-141 first have to decide which market they are in. The lawful prescription route runs through a licensed prescriber and a pharmacy dispensing Vyleesi. Everything else is the research-chemical market, and that market changed sharply in 2025 and 2026. Peptide Sciences closed in March 2026, Amino Asylum went offline after a reported federal raid in June 2025, and Paradigm Peptides ended in a criminal sentencing. Several sites now trade on those dead brand names, so the first check is not price. It is whether the company behind the storefront actually exists. Our guide to the best peptide companies in 2026 covers the current field vendor by vendor.

Five checks separate a documented PT-141 source from an anonymous one:

1. A lot-specific COA, published before purchase. The certificate should match the exact lot on the vial, not a generic product-page badge. The help center shows how to verify a certificate against your lot.
2. A named, independent laboratory. A COA is only as good as the lab that issued it. Court records in the Paradigm case showed the defendants admitted faking certificates outright, which is the failure mode this check exists to catch.
3. Identity and purity by more than one method. HPLC purity alone leaves an identity gap, and that gap is wider than usual for PT-141 because Melanotan II is close in mass. Look for LC-MS identity confirmation against 1025.18 g/mol, plus endotoxin results.
4. An identifiable company. A legal entity, a real contact route, and consistent policies. A brand name alone is not an identity, and the clone sites trading on dead vendors prove it.
5. Payment with recourse. Card payment carries buyer protection. Venmo, Zelle, and crypto-only checkouts remove it.

Curo does not stock PT-141 and has no product page for it, so nothing here is a pitch for a vial. The research catalog covers the categories Curo does list, every lot is tested by an independent laboratory for identity (LC-MS), purity (HPLC), and endotoxin, the full testing standard is documented, and every certificate is publicly readable without an account. Orders are fulfilled from the United States. The same five checks above are the ones to apply to any PT-141 supplier, and the comparison framework sets out how to run them side by side.

How much does PT-141 cost?

As of August 2026, research-grade PT-141 in the 10mg vial size typically runs $38 to $85 from US suppliers that publish lot-matched, independently issued COAs, with most listings clustered between $40 and $50. Cheaper vials exist, and so do heavily discounted multi-vial tiers, but the lowest prices cluster among suppliers with no published lot documentation, and an unverified lot is unusable as research material at any price. The approved prescription product is priced on a completely different basis, which is worth knowing before treating any research price as a comparison. Compare the documentation attached to the current batch first, then the price. The pre-purchase checklist walks the full sequence.

What a PT-141 certificate of analysis should show

PT-141 is synthesized by many suppliers, so material quality is something a lab confirms rather than assumes. Identity, purity, endotoxin load, and fill accuracy all vary by manufacturer and by lot. A certificate worth relying on shows:

• The exact lot number that appears on the vial.
• The issuing laboratory's name and report identifier.
• HPLC purity with the chromatogram, not a bare percentage.
• Mass-spectrometry identity confirmation against the expected 1025.18 g/mol, which is what separates PT-141 from its Melanotan II parent on paper.
• An endotoxin result, since a pure peptide can still carry bacterial contamination from synthesis.
• A way to verify the document independently, through a public lookup or the lab itself. Curo's COA database is open for exactly this reason.

A well-tested lyophilized peptide can still be degraded by poor handling after receipt. See storing research peptides and bacteriostatic water for the storage side.

For a broader framework on separating documentation from marketing when comparing suppliers, see how to evaluate research peptide companies and the companion piece on purity claims and COA batch documentation.

Further reading

KPV is the other melanocortin-family fragment with a settled mechanism question, and the answer went a direction nobody expected: the transporter it depends on can be knocked out, and the effect goes with it. That evidence is set out in KPV enters cells through PepT1, not a melanocortin receptor.

Semax carries the same family lineage into a different research area, with a long Russian clinical literature and no registered US intervention studies. The contrast with an FDA-reviewed record is drawn out in the Semax profile.

Tesamorelin is the cleanest comparison for what an approved product does and does not confer on a compound, covered in tesamorelin, a peptide with a drug label.

Frequently asked questions

Are PT-141 and bremelanotide the same compound?

Yes. FDA's substance registry places "PT-141 FREE BASE" in the synonym list for bremelanotide free base under UNII 6Y24O4F92S, with CAS number 189691-06-3.

Is PT-141 the same as Melanotan II?

No. The literature describes PT-141 as the carboxylate derivative of Melanotan II. They are chemically related but distinct molecules, close enough in mass that identity should be confirmed by mass spectrometry rather than assumed.

Is PT-141 legal to buy in the US?

It depends on which form. Bremelanotide is lawfully available by prescription as Vyleesi, within that product's label. Raw PT-141 is sold as a research chemical for laboratory use and is not a controlled substance as of August 2026. The research form is not approved for human use, and selling it for human consumption is what federal cases have targeted.

Where can a researcher buy PT-141?

From suppliers that publish lot-specific, independently issued COAs and operate as identifiable companies. Several well-known vendors closed or faced federal action in 2025 and 2026, and clone sites now trade on their names, so verify the company before the price. Curo does not stock PT-141.

How much does PT-141 cost?

Suppliers that publish lot-matched third-party COAs typically charge $38 to $85 for a 10mg research vial as of August 2026, with most listings between $40 and $50. Vials below that range usually come without verifiable lot documentation. The approved prescription product is priced on an entirely different basis.

What did FDA approve?

FDA approved Vyleesi under NDA 210557 on June 21, 2019 for premenopausal women with acquired, generalised hypoactive sexual desire disorder.

What does the Vyleesi label exclude?

The label excludes hypoactive sexual desire disorder in postmenopausal women and men, and it excludes enhancement of sexual performance. It also lists contraindications in uncontrolled hypertension and known cardiovascular disease.

Does Curo have a PT-141 product page?

No. This compound profile is a research reference, not a Curo product listing.

What should a certificate of analysis for PT-141 show?

Lot-specific identity and purity data from chromatographic and mass-spectrometry methods, plus endotoxin results, tied to the exact lot number on the vial and verifiable through a public lookup.