PT-141 20mg Pen

This page covers the ProPeptide-labelled PT-141 pen. It carries a label claim of 20mg of peptide held in solution inside a 3mL cartridge, fitted in a pen-style housing. The material arrives as a liquid fill rather than a dry powder, so there is no preparation step between unpacking and bench storage.

Bremelanotide, known in early papers by its code PT-141, is a synthetic cyclic heptapeptide from the alpha-melanocyte-stimulating hormone (alpha-MSH) family. Early papers place it among the melanocortin receptor agonists, with activity reported at MC3R and MC4R, receptors tied to signalling in the central nervous system. That sets it apart from PDE5-class compounds, which act on the nitric-oxide pathway.

In June 2019 the U.S. FDA approved a branded bremelanotide product, Vyleesi. Remy Research does not sell that medicine. This pen is research material from a different source, and its label, testing and intended use are separate from the approved product. We cite the official label only as a pharmacology and safety reference.

The pen is offered to laboratories running cell-culture and animal experiments. For research use only. Not for human or veterinary use. Background reading, with every citation, is on our PT-141 melanocortin research page.

Remy Research lists PT-141 in two ProPeptide formats. The peptide is the same; packaging, quantity and testing coverage are not.

A liquid fill, not a freeze-dried cake

The pen holds bremelanotide already in solution. Labs that prefer one sealed container per study series, or want to avoid weighing and preparing a powder, often pick a cartridge. Labs that need to set their own working concentration, or want the better long-term stability of dry material, usually choose the PT-141 10mg vial.

Twice the label quantity

Each cartridge is labelled at 20mg in 3mL, double the content of the single vial. That can simplify stock-keeping when one study runs over several weeks.

A batch report you can check

This pen has a published third-party report. Janoshik Analytical tested batch PT20P-001 by HPLC and recorded 99.703% peptide purity at a measured 6.84 mg/mL, close to the roughly 6.67 mg/mL implied by the label claim. The lab noted that its purity figure covers peptide peaks only, and the report does not confirm identity by mass spectrometry or the salt form. The scans and Janoshik verification key are on the PT20P-001 batch page. That report applies to this pen batch only, not to the vial.

Liquids need steady cold storage

Dissolved peptide degrades faster than dry peptide when it is warmed, frozen or left in light. Put the carton in a fridge as soon as it arrives. The chemistry behind this is covered in the peptide storage guide.

Chilled courier across the UAE

Orders go out with a cold-chain courier in insulated packaging rated for 2–8°C. Dubai orders in before 4 PM arrive the same day; elsewhere in the UAE, a noon cut-off gives next-day delivery. Full terms are on the delivery page.

Bremelanotide has a longer human record than most catalogue peptides, because it went through a full drug-development programme. The points below summarise what published studies and the U.S. label describe. They are findings from controlled settings, not outcomes anyone should expect.

A broad melanocortin agonist

Molinoff and colleagues (2003) described PT-141 as an alpha-MSH analogue with agonist activity at MC3R and MC4R. The later U.S. label adds MC1R, the receptor on pigment cells, which explains why skin darkening appears among its documented effects. Neither PT-141 nor the related Melanotan II is cleanly selective for one receptor.

From early studies to phase 3

The human programme moved in three steps. Early placebo-controlled work in 2004 tested an intranasal form. A randomized, placebo-controlled range-finding trial in premenopausal women followed in 2016, and two RECONNECT phase 3 trials were published in 2019. Those studies reported changes in validated questionnaire endpoints and fed into the FDA approval.

Official pharmacokinetic values

For the approved product, the label reports peak blood levels at a median of roughly 1 hour, a mean terminal half-life near 2.7 hours and 21% protein binding. These describe the licensed medicine and are reference figures only.

Tolerability signals researchers track

Ambulatory monitoring in a 2017 study found short-lived rises in blood pressure compared with placebo. The label also lists nausea and focal hyperpigmentation. Any melanocortin study design has to account for these signals.

PT-141 and Melanotan II

The two compounds share a melanocortin scaffold and are often confused. PT-141 has primary trials and official label material behind it, while Melanotan II rests mostly on preclinical and observational reports. Our PT-141 vs Melanotan II comparison sets the differences out.