Compare Peptides

Select any two compounds for a side-by-side comparison of mechanism, uses, risks, and FDA regulatory status.

Popular comparisons

Setmelanotide

Imcivree, RM-493

FDA Approved
Metabolic

PT-141

Bremelanotide, Vyleesi

FDA Approved
Melanocortin & Sexual Health
Overview

An MC4R (melanocortin 4 receptor) agonist FDA-approved for rare genetic obesity disorders including POMC, PCSK1, and LEPR deficiency. Represents a precision medicine approach to obesity treatment.

A synthetic melanocortin receptor agonist derived from Melanotan II. Unlike Melanotan II, PT-141 was developed specifically for sexual dysfunction and received FDA approval in 2019 as Vyleesi for hypoactive sexual desire disorder (HSDD) in premenopausal women.

Mechanism of Action

Activates the MC4R pathway in the hypothalamus, restoring satiety signaling that is disrupted in specific genetic obesity conditions. Unlike GLP-1 agonists, it targets the melanocortin pathway directly.

Activates melanocortin receptors (MC3R and MC4R) in the central nervous system, increasing sexual desire through a brain-based mechanism rather than vascular effects. This distinguishes it from PDE5 inhibitors like sildenafil which work peripherally.

Common Uses
  • Rare genetic obesity (POMC deficiency)
  • PCSK1 deficiency obesity
  • LEPR deficiency obesity
  • Female sexual dysfunction (FDA-approved indication)
  • Male sexual dysfunction (off-label)
  • Libido enhancement
  • Erectile dysfunction (off-label)
Known Risks
  • Skin hyperpigmentation (common)
  • Injection site reactions
  • Depression and suicidal ideation (boxed warning)
  • Spontaneous penile erections
  • Very narrow approved indication
  • Nausea (most common side effect — ~40% in trials)
  • Flushing
  • Headache
  • Transient blood pressure increase
  • Hyperpigmentation with repeated use
  • Injection site reactions
Regulatory Status
FDA Approved

FDA-approved as Imcivree (2020) for chronic weight management in patients 6+ years with obesity due to POMC, PCSK1, or LEPR deficiency confirmed by genetic testing. Not approved for general obesity.

FDA Approved

FDA-approved as Vyleesi (bremelanotide injection) in June 2019 for hypoactive sexual desire disorder (HSDD) in premenopausal women. Off-label use for male sexual dysfunction is common through telehealth clinics. Available through compounding pharmacies with prescription.

This comparison is for educational purposes only and does not constitute medical advice. Always consult a qualified healthcare professional before starting any peptide therapy.