Back to Encyclopedia

PT-141 (Bremelanotide)

Sexual Health

Also known as: Bremelanotide, Vyleesi

Half-life: ~2.7 hours

Sexual Health

Overview

PT-141 (bremelanotide) is a synthetic cyclic heptapeptide melanocortin receptor agonist derived from Melanotan II. Unlike phosphodiesterase inhibitors (such as sildenafil) that act on vascular smooth muscle, PT-141 works through the central nervous system by activating melanocortin-4 receptors (MC4R) in the brain, directly stimulating sexual desire and arousal pathways. This unique mechanism of action makes it the first medication to target the neurological basis of sexual desire rather than peripheral blood flow.

In June 2019, the FDA approved bremelanotide as Vyleesi for the treatment of hypoactive sexual desire disorder (HSDD) in premenopausal women, making it the first injectable medication for this indication. The approval was based on two Phase 3 RECONNECT trials involving over 1,200 premenopausal women, which demonstrated statistically significant improvements in sexual desire and reductions in distress associated with low sexual desire. PT-141 is administered subcutaneously at least 45 minutes before anticipated sexual activity.

While the FDA approval is specifically for HSDD in premenopausal women, PT-141 has also shown efficacy in clinical studies for erectile dysfunction in men and is used off-label in the wellness community for both sexes. The primary side effects include nausea (approximately 40% of users), flushing, and a transient increase in blood pressure. The FDA label restricts use to no more than once in 24 hours and no more than 8 doses per month.

History

PT-141 (bremelanotide) was developed by Palatin Technologies as a derivative of Melanotan II. During the University of Arizona's clinical trials with Melanotan II in the 1990s, researchers noticed unexpected and significant sexual arousal effects. Palatin Technologies created PT-141 as a cyclic metabolite of Melanotan II with more selective activity at melanocortin-4 receptors, designed specifically for sexual dysfunction. Initial development targeted erectile dysfunction in men via intranasal delivery, but a Phase 2b trial was halted due to blood pressure concerns. The focus shifted to subcutaneous delivery for female sexual dysfunction. Two Phase 3 RECONNECT trials in over 1,200 premenopausal women led to FDA approval of Vyleesi (bremelanotide) in June 2019 for hypoactive sexual desire disorder (HSDD), making it the first injectable medication for this indication.

Effects

  • Increases sexual desire and arousal via central MC4R activation
  • Reduces distress associated with low sexual desire
  • Enhances erectile function in men (off-label)
  • Acts through neurological pathways rather than vascular mechanisms
  • Effective in both men and women for sexual dysfunction

Side Effects

  • Nausea (approximately 40% of users, typically resolves within 2 hours)
  • Facial flushing and warmth
  • Headache
  • Transient increase in blood pressure (primarily systolic)
  • Injection site reactions

Tolerability

PT-141 has a moderate tolerability profile with well-characterized side effects from Phase 3 clinical trials. Nausea is the most common side effect, occurring in approximately 40% of users but typically lasting less than 2 hours. Flushing and headache are also common. A transient increase in blood pressure (particularly systolic) occurs and is the main safety concern, leading to restrictions against use in patients with uncontrolled hypertension or cardiovascular disease. The FDA label limits use to no more than once in 24 hours and no more than 8 times per month. Despite the nausea burden, patient satisfaction in trials was generally positive due to the meaningful improvement in sexual desire.

Dosing Ranges

HSDD treatment (FDA-approved dose)

Dose Range

1750 mcg

Frequency

As needed, at least 45 minutes before activity

Duration

As needed, max 8 doses per month

General sexual function enhancement

Dose Range

1000-2000 mcg

Frequency

As needed, 45-60 minutes before activity

Duration

As needed

Dosing information is for educational purposes only. Consult a healthcare professional before using any peptide.

Reconstitution

Preparation Details

Typical Vial Size

10 mg

Water Type

Bacteriostatic water (BAC water)

Mixing Volume

2 mL

Half-Life

~2.7 hours

Molecular Weight

1025.2 Da

Vyleesi (pharmaceutical) is supplied as pre-filled syringes at 1.75 mg dose. Store refrigerated at 2-8°C. Research-grade PT-141 is reconstituted with BAC water and administered 45-60 minutes before anticipated sexual activity.

Regulatory Status

FDA Status

FDA approved. Bremelanotide (Vyleesi) was approved in June 2019 for treatment of hypoactive sexual desire disorder (HSDD) in premenopausal women.

Legal Status

Prescription medication in the USA (as Vyleesi). Research chemical in most other countries. Not approved outside the USA.

USA

Approved

FDA approved Vyleesi June 2019 for HSDD in premenopausal women

EU

Not approved

EMA has not authorized

UK

Not approved

Not licensed by MHRA

Australia

Not approved

Not evaluated by TGA

Canada

Not approved

Not authorized by Health Canada

Russia

Not approved

Not authorized

Cited Studies

Bremelanotide for hypoactive sexual desire disorder: A randomized, double-blind, placebo-controlled, dose-finding trial (RECONNECT)

Kingsberg SA, Clayton AH, Portman D, Williams LA, Krop J, Jordan R, Lucas J, Simon JA

Obstetrics and Gynecology (2019)

Phase 3 pivotal trial demonstrating that bremelanotide significantly improves sexual desire and reduces distress in premenopausal women with HSDD, forming the basis for FDA approval.

View Study →

Bremelanotide: new drug for hypoactive sexual desire disorder in premenopausal women

Simon JA, Kingsberg SA, Portman D, Williams LA, Krop J, Jordan R, Lucas J, Clayton AH

Journal of the American Medical Association (2019)

Comprehensive analysis of the RECONNECT trial program, confirming the efficacy and safety profile of bremelanotide for HSDD treatment.

View Study →

Melanocortin receptor agonists, penile erection, and sexual motivation: human studies with Melanotan II

Wessells H, Levine N, Hadley ME, Dorr R, Hruby VJ

International Journal of Impotence Research (2000)

Early clinical work establishing that melanocortin agonists induce erections and sexual motivation in men, providing the foundational evidence for PT-141 development.

View Study →

Track PT-141 (Bremelanotide) and more with PinnyPeptide.

Sign Up to Track