Kisspeptin-10: natural hormone that triggers puberty, fertility, and sex-hormone release
A natural brain signal that tells the body to release sex hormones; studied to trigger egg maturation in IVF with lower ovarian over-stimulation risk, and to treat low sexual desire; experimental, not yet an approved drug.
- Class
- Endogenous neuropeptide fragment — HPG axis trigger
- Status
- Research stage. No FDA or EMA approval. Used in UK academic clinical research under investigator protocols (Imperial College London and affiliated centers).
- Best-supported effect
- Modulation of sexual brain processing (fMRI) and penile tumescence in adults with HSDD in Phase 1–2 IV-infusion trials (single center); HPG axis stimulation (LH/FSH/testosterone) confirmed in mechanistic human studies.
- Main caveat
- All published human efficacy evidence from one research center (Imperial College London) at small scale (n=32 per arm); no Phase 3 data; community SC-injection use has no matching studied evidence base; fertility/IVF trial evidence in the compiled source used kisspeptin-54, not kisspeptin-10.
A researcher, an agent, or an algorithm wrote down the sequence and picked a target to hit.
An AI model like OpenFold3 or AlphaFold built a 3D structure and scored how well it fits the binding site.
A second contributor repeated the computation on their own hardware and the scores matched.
A chemistry service or a researcher ordered the sequence, it was manufactured, and mass spectrometry confirmed the right molecule was produced.
A binding or activity measurement confirmed that it actually does what the computer predicted — or didn't.
What this is
Kisspeptin-10 is the 10-amino-acid C-terminal active fragment of kisspeptin, an endogenous neuropeptide produced in the hypothalamus. It is the shortest isoform that retains full agonist activity at the KISS1R receptor (also called GPR54), and it functions as the master upstream trigger of the hypothalamic-pituitary-gonadal (HPG) axis: kisspeptin-10 activates GnRH neurons, GnRH drives pituitary release of LH and FSH, and LH/FSH in turn control gonadal production of testosterone and estrogen. The raw sequence stored here (YNWNSFGLRF) is the standard 1-letter representation; the biologically active form carries a C-terminal amide (Phe-NH₂), which is naturally present in the endogenous fragment and is not reflected in the stored sequence.
Kisspeptin-10 should be distinguished from kisspeptin-54, the longer-acting full-length isoform used in most fertility and IVF trigger trials. Evidence from kisspeptin-54 trials does not automatically extend to kisspeptin-10; published literature explicitly flags this distinction.
History
Kisspeptin was discovered in 1996 at Pennsylvania State University's Hershey Medical Center as a product of the KISS1 metastasis-suppressor gene — named in a nod to the town's Hershey's Kisses. Its reproductive function was not recognized until 2003, when independent groups led by Stéphanie Seminara at Massachusetts General Hospital and Nicolas de Roux at INSERM in Paris showed that humans carrying inactivating mutations in KISS1R fail to undergo puberty entirely — establishing kisspeptin as the upstream master regulator of human reproduction. Clinical research in sexual medicine and fertility has since been led predominantly by Prof. Waljit Dhillo and colleagues at Imperial College London, producing the primary published human evidence base for this peptide.
What it does
Kisspeptin-10 activates GnRH neurons in the hypothalamus, triggering the hormonal cascade that drives testosterone production in men and estrogen production in women. In clinical studies it has raised LH and FSH within minutes of administration (George and colleagues, 2011). Beyond its hormonal effects, it modulates brain regions involved in sexual arousal and processing — including areas such as the posterior cingulate cortex and hippocampus — in ways that appear partially independent of downstream gonadal hormone release. This dual action (HPG axis activation and direct central sexual-brain modulation) distinguishes kisspeptin-10 from purely peripheral reproductive hormones.
A notable limitation for sustained use: continuous or frequent administration leads to tachyphylaxis at the kisspeptin receptor, making chronic HPG-axis stimulation difficult. Published studies specifically document that chronic administration causes receptor desensitization (Jayasena and colleagues, 2009).
Evidence
- Human: Phase 1–2 crossover RCTs conducted at Imperial College London demonstrated that kisspeptin-10 IV infusion improved sexual brain processing (fMRI) and increased penile tumescence by approximately 56% versus placebo in men with hypoactive sexual desire disorder (HSDD); a parallel trial in women with HSDD showed enhanced sexual brain processing and reduced sexual aversion (Mills and colleagues, 2023; Thurston and colleagues, 2022). Mechanistic studies established HPG axis dose-response in healthy men across IV bolus and infusion arms, and a separate study found HPG axis responses in men with type-2-diabetes-associated hypogonadism (George and colleagues, 2011). A 2025 study reported no anxiety provocation at biologically active doses. All published human efficacy data originate from a single research center; no Phase 3 trials for kisspeptin-10 specifically have been completed. IVF oocyte-maturation trigger trials (which showed reduced ovarian hyperstimulation syndrome risk) used kisspeptin-54, not kisspeptin-10, and their findings do not directly transfer.
- Animal: No animal efficacy data for kisspeptin-10 individually are identified in the available literature.
- In vitro: No cell or binding assay data for kisspeptin-10 are identified in the available literature.
Known effects
- HPG axis stimulation (LH/FSH/testosterone rise) — Supported by human mechanistic studies (Phase 1, IV route)
- Sexual brain processing modulation in HSDD — Phase 1–2 human RCT evidence (IV infusion, single center)
- Penile tumescence increase in men with HSDD — Phase 1–2 human RCT evidence (IV infusion, single center)
- Improved sexual brain processing in women with HSDD — Phase 1–2 human RCT evidence (IV infusion, single center)
- IVF oocyte maturation triggering with reduced OHSS risk — Evidence is for kisspeptin-54, not kisspeptin-10
Safety signals
Transient flushing is the most commonly reported adverse event across published Phase 1–2 IV-infusion trials at Imperial College London; mild headache has been reported infrequently. No serious adverse events were reported in the published supervised IV-infusion protocols. A short-protocol study published in 2025 found no anxiety signal at biologically active doses. Plasma half-life is approximately 4–5 minutes, which limits cumulative exposure in IV-infusion settings. Long-term safety data are absent from the published literature for any route or population; the existing safety record applies specifically to short-duration, IV-route, supervised research protocols and does not characterize risks of repeated subcutaneous administration.
Regulatory status
- US (FDA): Not approved for any indication; classified as a research compound. No late-stage regulatory filing is described as pending in the available literature.
- EU (EMA): Not approved. Used in UK academic clinical research under investigator protocols.
- UK: Investigator-protocol research use at Imperial College London and affiliated academic centers; not a licensed medicine.
- WADA: Per available sources as of 2025, kisspeptin-10 is not explicitly listed by name; current status on the WADA prohibited list was not independently refreshed for this card.
Mechanism
Kisspeptin-10 acts as a full agonist at KISS1R (GPR54), a G protein-coupled receptor expressed on GnRH neurons in the hypothalamus. Agonism at KISS1R triggers depolarization of GnRH neurons and GnRH release into the hypothalamic-pituitary portal circulation. GnRH then binds pituitary gonadotroph receptors to drive pulsatile release of LH and FSH, which act on the gonads to stimulate testosterone synthesis in men and estrogen/progesterone synthesis in women. The requirement of functional kisspeptin-KISS1R signaling for puberty onset is established by loss-of-function genetic evidence in humans: individuals with inactivating KISS1R mutations fail to undergo puberty and present with hypogonadotropic hypogonadism (de Roux and colleagues, 2003). Kisspeptin neurons also integrate metabolic, circadian, and stress signals, positioning the peptide as a convergence point for systemic physiological state and reproductive readiness.
Kisspeptin-10 also independently modulates brain regions involved in sexual arousal — including the posterior cingulate cortex, hippocampus, and globus pallidus — through mechanisms that appear partially independent of downstream gonadal hormone release (Izzi-Engbeaya and colleagues, 2019; Tsoutsouki and colleagues, 2022).
Open questions
- Independent replication: All published kisspeptin-10 HSDD efficacy data originate from a single research center (Imperial College London). Whether results replicate in independent populations and at other institutions is unresolved.
- Route translation: Human clinical evidence used IV infusion. Whether subcutaneous administration achieves comparable HPG axis activation or central sexual-brain effects — given the very short plasma half-life of approximately 4–5 minutes — is not established in the published literature.
- Phase 3 data: No Phase 3 trials for kisspeptin-10 in HSDD or any other indication are described as completed or underway in the available literature.
- KP-10 vs KP-54 in fertility: Most IVF and fertility evidence used kisspeptin-54. Whether kisspeptin-10 performs equivalently in those contexts, given differing pharmacokinetics, is not addressed in the published literature.
- Long-term safety: No chronic exposure data exist in the published literature for any route or population.
- Postmenopausal HSDD: A registered trial in postmenopausal women with HSDD was ongoing as of October 2023; results are not yet in the published record.
Related peptides
- Kisspeptin-54 — the full-length 54-amino-acid parent isoform; most IVF oocyte-maturation trigger trials used this form, not kisspeptin-10. A separate platform card covers kisspeptin-54.
- GnRH (Gonadorelin) — the downstream target of kisspeptin signaling; binds pituitary gonadotroph receptors to release LH and FSH.
Research directions for this peptide, selected from the current sources — hypotheses you can explore and model. None of it is proven yet; tap any one to see the full thinking.
Could the shortest active form of kisspeptin, which clears the body faster, preserve the pulsing hormone pattern that fertility depends on better than the longer version being tested in IVF?
If true, women with hormone-driven infertility might respond better to a treatment matched to the body's own rapid signaling rhythm, reducing the risk that the drug loses effectiveness over time. This could open a simpler option for restoring natural cycles without the side-effects of conventional hormone therapies.
Is the small chemical group added to the end of kisspeptin-10 in the body a true part of the binding grip on the receptor, meaning that research using the uncapped version is measuring a fundamentally different compound?
If true, a large body of published kisspeptin-10 pharmacology may need reinterpretation, and drug developers would need to ensure correct amidation to avoid testing an inadvertent partial agonist. This matters for anyone designing kisspeptin-based fertility or anti-cancer drugs.
Could a tiny fragment of kisspeptin made within the placenta itself play a role in keeping early pregnancy stable, and could low levels of this signal contribute to miscarriage?
If true, measuring or restoring this local signal might provide doctors with a new early-pregnancy biomarker or treatment target, potentially preventing some of the roughly one-in-five pregnancies that end in miscarriage before 12 weeks.
Could the body's own fertility-triggering peptide also slow the spread of certain cancers by activating the receptor that suppresses metastasis?
If true, a natural hormone fragment already known to be safe in humans could potentially be added to cancer treatment to reduce the risk of tumors spreading, without the full hormonal side effects of activating the body's fertility system at high doses.
Does kisspeptin-10 affect body weight, fat distribution, or blood sugar differently in men and women, through the same receptor it uses for fertility signaling?
If true, kisspeptin-10 might become a useful research tool for understanding why metabolic diseases like obesity and type 2 diabetes affect men and women differently, and could suggest new sex-tailored treatment strategies.
▸full evidence table2 metrics
| metric | value | tool |
|---|---|---|
| ipTM | 0.9427151083946228 | boltz-2 |
| ranking score | 0.7692812085151672 | boltz-2 |
▸3-letter notation
▸recipeboltz-2 2.2.1
| parameter | value |
|---|---|
| model | boltz-2 2.2.1 |
| weights | — |
| hardware | vast_v100_32gb |
| mlx version | — |
| python | — |
| random seed | 1 |
| msa strategy | colabfold_local |
| runtime | — |
| predicted by | — |
| predicted at | 2026-05-22 |
▸citationbibtex
@peptide{pep10710,
sequence = {YNWNSFGLRF},
target = {kiss1r},
author = {peptidemodel},
year = {2026},
status = {synthesized}
}