We sometimes see men asking about PT-141 (bremelanotide) in ED discussion forums. Despite apparent interest, there doesn’t seem to be much information available.
We researched PT-141, and found four somewhat dated clinical studies1 2 3 4.
The conclusion seems to be that PT-141 was a promising treatment, with moderate, well-tolerated side effects. The most common reported side-effect was nausea. In some cases, it allows men who do not respond to PDE5 inhibitors to achieve erections.
However, in 2007, after analyzing data from Phase 1 & 2 trials, the FDA questioned both efficacy and clinical benefits, and identified blood-pressure elevation as its principal safety concern. King Pharmaceuticals chose to discontinue testing, and there has been no further research on the effectiveness of PT-141 as a treatment for erectile dysfunction.
Note that PT-141 is used for for other conditions. In 2019, it was approved by the FDA as a treatment for premenopausal women with Hypoactive Sexual Desire Disorder (HSSD)5, indicating that it is regarded as generally safe.
In 2024, Palatin Technologies announced a clinical study to test PT-141 in combination with PDE5 inhibitors for men who do not respond to PDE5 inhibitors alone. The results of that study have no been published.
What is PT-141?
PT-141 is a peptide (a cyclic heptapeptide melanocortin analog) that primarily affects the nervous system. This may indicate that it is not an effective treatment for men with vasculogenic erectile dysfunction. However, patients who do not respond to PDE-5 inhibitors showed a statistically significant response to PT-141.
PT-141 can be administered as an injection, or as a nasal spray.
Is It Safe?
PT-141 is contraindicated for men with hypertension or cardiovascular disease. Talk to your doctor before experimenting with PT-141.
How to Buy PT-141
According to peptides.org, “While PT-141 is widely available online, researchers may find that securing a reliable source of research-grade bremelanotide is challenging. Our team has found that many vendors claiming to offer high-quality PT-141 fall short of the mark.”
Peptides.org recommends Peptide Sciences as a source for high-quality PT-141, but we have not verified their assessment.
References
- Diamond, L E ; Earle, D C ; Rosen, R C; Willett, M S; Molinoff, P B. “Double-blind, placebo-controlled evaluation of the safety, pharmacokinetic properties and pharmacodynamic effects of intranasal PT-141, a melanocortin receptor agonist, in healthy males and patients with mild-to-moderate erectile dysfunction.” International Journal of Impotence Research. Feb 2004;16(1):51-9.
<https://pubmed.ncbi.nlm.nih.gov/14963471/> - Molinoff, P B; Shadiack, A M; Earle, D; Diamond, L E; Quon C Y. “PT-141: a melanocortin agonist for the treatment of sexual dysfunction.” Annals of the New York Academy of Sciences. Jun 2003;994:96-102.
<https://pubmed.ncbi.nlm.nih.gov/12851303/> - Rosen, R C; Diamond, L E; Earle, D C; Shadiack, A M; Molinoff, P B. “Evaluation of the safety, pharmacokinetics and pharmacodynamic effects of subcutaneously administered PT-141, a melanocortin receptor agonist, in healthy male subjects and in patients with an inadequate response to Viagra.” International Journal of Impotence Research. Apr 2004;16(2):135-42.
<https://pubmed.ncbi.nlm.nih.gov/14999221/> - Safarinejad, Mohammad Reza; Hosseini, Seyyed Yousof. “Salvage of Sildenafil Failures With Bremelanotide: A Randomized, Double-Blind, Placebo Controlled Study.” The Journal of Urology. March 2008.
<https://www.auajournals.org/doi/full/10.1016/j.juro.2007.10.063> - Dhillon,Sohita ; Keam, Susan J. “Bremelanotide: First Approval.” Drugs. Sep 2019;79(14):1599-1606.
<https://pubmed.ncbi.nlm.nih.gov/31429064/>