I overstated how interesting this kisspeptin study is.
Four problems:
1) Only 32 men completed the trial (all diagnosed with HSDD, not ED)
2) The active treatment was a single 75-minute IV infusion which doesn't really tell us whether effects continue with repeated/long-term use
3) The primary endpoint was changes in brain activity, not better sex or erections or quality of life
4) The 56% was the difference in penile tumescence, not improvement in erectile function
The study is a neat mechanistic proof-of-concept, but as evidence for kisspeptin being a serious ED drug, it's a bit of a dud.
A peptide increased penile enlargement during sexual arousal by up to 56% vs placebo.
Kisspeptin also changed activity across the brain’s sexual-processing network.
This could be a replacement for the 300M ED drugs sold in the US every year.