PT-141 (Bremelanotide): What It Is and U.S. Status

What is PT-141?

PT-141 is the development code for bremelanotide, a synthetic peptide that acts on melanocortin receptors. Bremelanotide is FDA-approved as a prescription medicine under the brand name Vyleesi, but only for one specific use in premenopausal women. Products sold online as "PT-141" are not Vyleesi and are not covered by that approval.

How it works

Melanocortin receptors respond to natural hormones such as alpha-melanocyte-stimulating hormone (alpha-MSH). Different receptor subtypes are involved in skin pigment, appetite, sexual function and other processes. According to the Vyleesi label, bremelanotide activates several of these subtypes, with the MC1 and MC4 receptors most relevant at the levels reached in clinical use. The label states that the exact way it acts on low sexual desire is not known.

Development history

Bremelanotide was developed by Palatin Technologies out of earlier research on melanotan II, a related research peptide. It is a different compound from melanotan II, with its own clinical program and approval.

The FDA approved Vyleesi on June 21, 2019. The approval was based on two identical phase 3, randomized, double-blind, placebo-controlled trials lasting 24 weeks in a combined 1,247 premenopausal women with acquired, generalized hypoactive sexual desire disorder (HSDD). The trials measured changes in a sexual desire score and in a score for distress related to low desire.

In December 2023, Palatin sold its worldwide rights to Vyleesi to Cosette Pharmaceuticals, which is the current labeler.

Approved use and its limits

Vyleesi is approved for premenopausal women with acquired, generalized HSDD. This means low sexual desire that causes marked distress and is not due to another medical or mental health condition, problems in the relationship, or the effects of a medication or other drug.

The label states that Vyleesi is not approved for postmenopausal women or for men, and that it is not meant to enhance sexual performance.

Documented safety information

The Vyleesi label includes the following safety information, among other details:

• It should not be used by people with uncontrolled high blood pressure or known cardiovascular disease.
• It can cause a temporary rise in blood pressure and a drop in heart rate after each use, usually resolving within 12 hours.
• Nausea was reported by 40% of patients in clinical trials. Other common reactions included flushing, reactions where the shot was given, headache and vomiting.
• Darkening of patches of skin (focal hyperpigmentation) was reported, more often in people with darker skin, and may not fully fade after stopping.
• It may greatly lower the levels of naltrexone taken by mouth, so it should be avoided with oral naltrexone products used for alcohol or opioid dependence.

U.S. regulatory status

Current status: FDA-approved prescription drug (Rx only).

The FDA approval covers Vyleesi itself, which is made under FDA oversight, prescribed by a licensed healthcare provider and dispensed by a licensed pharmacy. A prescriber typically reviews blood pressure and heart health before deciding whether it is appropriate.

The approval does not extend to products sold as "PT-141" through websites, which are often labeled "for research purposes only" or "not for human consumption." Those products are not approved medicines, and the FDA has not reviewed their contents, purity or strength.

Why Peptide Labs does not sell PT-141

Peptide Labs does not sell this compound. This page is general information, not medical advice. We do not supply bremelanotide, and we do not point readers to anyone who does.

For personal medical questions, including questions about bremelanotide, the right person to ask is a licensed healthcare provider.

Related reading

See the full list of compound profiles in the Peptide Guide. Related melanocortin peptides: melanotan II and melanotan I (afamelanotide). For background, read what peptides are.