PT-141

Key points

• PT-141 (bremelanotide) is a seven amino acid peptide that activates melanocortin receptors in the brain.
• Unlike the common erection tablets, it works on desire centrally, not on blood flow.
• It is licensed in some countries, including the United States (sold as Vyleesi), for a specific type of low sexual desire in premenopausal women.
• It has no UK marketing authorisation. Use in men is not an approved use anywhere.

Quick facts

What it is

Melanocortin receptor agonist, 7 amino acids (bremelanotide)

Approved use

Low sexual desire in premenopausal women (some countries)

UK status

Not a licensed medicine; no UK marketing authorisation

Note

Can briefly raise blood pressure

How it works

PT-141 activates melanocortin receptors, mainly in the hypothalamus, a part of the brain involved in sexual arousal. This is a different approach from tablets such as sildenafil, which work on blood flow. Because it acts on brain signalling rather than the circulation, it is being looked at for low desire as well as erectile difficulty.

What the evidence shows

Its approved use in women rests on two late stage placebo controlled trials, where the average benefit was modest. In men with erectile difficulty the evidence is earlier, from mid stage studies, including some men who had not responded to the usual tablets. There is no completed late stage trial of the approved injectable in men, so male use remains off the approved path.

What it does not settle

• The average benefit in the approved use is modest, and it does not suit everyone.
• Long term safety, and use in men and in postmenopausal women, are less well studied.
• There is no long term heart outcome data.

Side effects

Common

• Nausea is the most common effect and depends on the dose. Flushing, injection site reactions and mild headache are also reported.

Less common but serious

• It can cause a short lived rise in blood pressure, so it is not suitable for people with uncontrolled high blood pressure or known heart disease.
• Repeated use can cause darkening of patches of skin, including on the face and gums.

Report any suspected side effect through the MHRA Yellow Card scheme.

UK legal status and access

PT-141 has no UK marketing authorisation, so it is not a licensed medicine here. Its licensed use in other countries is on prescription after assessment. Products sold online without a prescription are unlicensed, and their dose and contents cannot be verified.

Common questions