Kisspeptin-54 (Metastin)
Also known as: Kp-54
Kisspeptin-54 (Metastin), also called Kp-54, is a research peptide in the GnRH Modulator class. Kisspeptin-54 is the full-length product of the KISS1 gene, originally described as metastin for its reported suppression of tumour metastasis.
For research use only.
Key Facts
- CAS
- 374675-16-8
- Molecular Weight (MW)
- ≈5857 g/mol
- Half-life
- Short; study-dependent
- FDA status
- Not Approved
- Evidence level
- Limited Human Evidence
- Human dose established
- Yes
- Administration Route
- Subcutaneous infusion · Intravenous
- Frequency
- Continuous infusion over 8 hours in the published study
- Last updated
- Sep 6, 2026
- Reviewed
- Aug 30, 2026
- Targets
- KISS1R
Vendor price snapshot
Each vendor counts once, at the median price per mg of its own listings; the typical range is the middle half of vendors. From public vendor listings collected between Dec 2025 and Sep 2026, so confirm the live price on the vendor site. Peptide Library does not sell peptides.
- Vendors listing this peptide
- 19
- Listed offers
- 27
- Median price per mg
- $8.00/mg
- Typical $5.75–$10.94/mg
Research summary
Full-length product of the KISS1 gene, originally described as metastin for its reported suppression of tumour metastasis. It acts on hypothalamic neurons upstream of GnRH release and is a gatekeeper of puberty and reproductive axis function; loss-of-function mutations in its receptor cause failure of puberty. It has been used in human reproductive-endocrine research, where its longer sequence gives a somewhat greater duration of action than kisspeptin-10. Not FDA-approved. Prohibited in sport under WADA class S2.
Peptide Library's Kisspeptin-54 (Metastin) profile summarises 5 cited studies listed in the Science section, the compound's regulatory status, and research-protocol parameters reported for it. It is a research reference, not medical advice.
Kisspeptin-54 (Metastin) dosage chart
Kisspeptin-54 has published human dosing from academic endocrine research: subcutaneous infusion at 0.1, 0.3 or 1.0 nmol/kg/h over 8 hours in healthy women, stimulating gonadotrophin release. That dosing is a weight-based infusion rate delivered in a research setting, not a self-administered regimen, and no product containing it is approved.
| Human dosing established | Yes |
|---|---|
| Studied dose range | 0.1-1.0 nmol/kg/h by subcutaneous infusion |
| Route | Subcutaneous infusion · Intravenous |
| Frequency | Continuous infusion over 8 hours in the published study |
| Duration studied | Acute, single-session protocols |
| Evidence level | Limited Human Evidence |
| Last reviewed | 2026-09-05 |
Research-reported dosing
Doses as studied, one row per regimen. Different trials used different regimens; they are listed separately rather than averaged.
| Study / context | Population | Dose | Route | Frequency | Duration | Outcome studied | Source |
|---|---|---|---|---|---|---|---|
| Subcutaneous infusion study in healthy women (2016)Clinical trial · Human endocrine physiology study | Healthy women (n=4), early follicular phase across 4 separate menstrual cycles | 0.1, 0.3 or 1.0 nmol/kg/h, or saline | Subcutaneous infusion | Continuous over 8 hours | 8-hour infusion per cycle | Luteinising hormone and gonadotrophin release, and its relationship to baseline oestradiol | Subcutaneous infusion of kisspeptin-54 stimulates gonadotrophin release in women. Clin Endocrinol (Oxf). 2016. |
| Reproductive hormone and anxiety study (2025)Clinical trial · Human physiology study | Human participants | Per study protocol | Intravenous | — | — | Reproductive hormones and anxiety measures | Kisspeptin Administration Stimulates Reproductive Hormones but Does Not Affect Anxiety in Humans. J Clin Endocrinol Metab. 2025. |
Where sources disagree
- Published dosing is an infusion rate in nanomoles per kilogram per hour, sustained over 8 hours under supervision. Kisspeptin sold for self-injection is dosed as a fixed bolus in micrograms; the two are not interchangeable, and a rate cannot be converted into a bolus without changing what was studied.
- Kisspeptin-54 and kisspeptin-10 are different lengths of the same parent peptide, and studies are indexed under kisspeptin, KP-54, KP-10, metastin and kisspeptin-112-121. Evidence for one length is not automatically evidence for the other.
- All published human work is acute and mechanistic, measuring a hormone response over hours. Nothing establishes a repeated-dosing regimen or its safety over time.
Reconstitution
Common research vial sizes: 5 mg, 10 mg.
| Vial | Bacteriostatic water | Concentration | Per 0.01 mL |
|---|---|---|---|
| 5 mg | 2 mL | 2.5 mg/mL | 25 mcg per 0.01 mL |
| 10 mg | 2 mL | 5 mg/mL | 50 mcg per 0.01 mL |
These figures are arithmetic only — they convert a vial and a volume into a concentration. They are not a recommendation to take any dose.
Calculate reconstitution & dose →Handling & administration
- Timing Notes
- Investigated for fertility/IVF applications
Sequence & molecular data
| Molecular formula | C258H401N79O78 |
|---|---|
| Molecular weight | ≈5857 g/mol |
| CAS number | 374675-16-8 |
| Half-life | Short; study-dependent |
| Appearance | White lyophilized powder |
| Formulation | Lyophilized Powder |
| PubChem CID | 71306396 |
| FDA UNII | 2VG74ZW2K5 |
Identifiers link to the public PubChem, FDA Substance Registration (UNII), ChEMBL and DrugBank records for the same entity.
Science
Mechanism of Action
Kisspeptin-54 is the full-length product of the KISS1 gene, originally described as metastin for its reported suppression of tumour metastasis. It acts at KISS1R on hypothalamic GnRH neurons, the signalling step that gates the entire reproductive axis: loss-of-function mutations in KISS1R cause hypogonadotropic hypogonadism and failure of puberty, which is what established kisspeptin as the upstream trigger of GnRH pulsatility. Receptor activation depolarises GnRH neurons and increases luteinising and follicle-stimulating hormone secretion. The longer full-length peptide has a somewhat greater duration of action than the kisspeptin-10 fragment, though both are short-lived.
Origin
Synthetic full-length kisspeptin-54.
Targets
Studies
- Circulatory metastin/kisspeptin-1 in polycystic ovary syndrome: a systematic review and meta-analysis with diagnostic test accuracy
- Safety Evaluation of KP-10 (Metastin 45-54) Following once Daily Intravenous Administration for 14 Days in Dog
- Kisspeptin receptor agonist has therapeutic potential for female reproductive disorders
- Distribution of the kisspeptin system and its relation with gonadotropin-releasing hormone in the hypothalamus
- Kisspeptin system-physiology and clinical perspectives
Regulatory & research status
Kisspeptin-54 (Metastin) is not an FDA-approved product. It is sold for laboratory research and has no approved medical use.
| FDA status | Not Approved |
|---|---|
| Availability | Research-Only |
| WADA (sport) | Banned in Sport |
| Library classification | Research-Only |
Benefits
Kisspeptin-54 (Metastin) side effects
Kisspeptin-54 (Metastin) has only limited human data, so the list below is incomplete and its side-effect profile is not well established.
Side Effects
- Injection reactions
- Reproductive-hormone swings
Storage & stability
Lyophilized (freeze-dried) peptide powder is far more stable than the reconstituted solution. Keep sealed vials cold, dry and away from light; long-term storage is typically frozen, with short-term refrigeration for vials in use.
Once reconstituted in bacteriostatic water, keep the solution refrigerated, avoid repeated freeze–thaw cycles and agitation, and label the vial with the reconstitution date and concentration. Discard any solution that turns cloudy or shows particulates.
Degradation rates differ by sequence: peptides containing methionine, cysteine, asparagine or glutamine are more prone to oxidation and deamidation, so shelf life after reconstitution is compound-specific rather than universal.
Read the full guide: how to store peptides before and after reconstitution →
Source: Manning MC, Chou DK, Murphy BM, Payne RW, Katayama DS. Stability of protein pharmaceuticals: an update. Pharm Res. 2010;27(4):544–575. (PMID 20143256). General guidance for research handling; not product-specific instructions.
Kisspeptin-54 (Metastin): frequently asked questions
What is Kisspeptin-54 (Metastin)?
Full-length product of the KISS1 gene, originally described as metastin for its reported suppression of tumour metastasis. It acts on hypothalamic neurons upstream of GnRH release and is a gatekeeper of puberty and reproductive axis function; loss-of-function mutations in its receptor cause failure of puberty. It has been used in human reproductive-endocrine research, where its longer sequence gives a somewhat greater duration of action than kisspeptin-10. Not FDA-approved. Prohibited in sport under WADA class S2.
How does Kisspeptin-54 (Metastin) work?
Kisspeptin-54 is the full-length product of the KISS1 gene, originally described as metastin for its reported suppression of tumour metastasis. It acts at KISS1R on hypothalamic GnRH neurons, the signalling step that gates the entire reproductive axis: loss-of-function mutations in KISS1R cause hypogonadotropic hypogonadism and failure of puberty, which is what established kisspeptin as the upstream trigger of GnRH pulsatility.
Is Kisspeptin-54 (Metastin) FDA approved?
No. Kisspeptin-54 (Metastin) is not approved by the FDA for any indication and is categorised as research-only. It has not been reviewed for safety or efficacy as a medicine, and published research should be read as investigation rather than established use.
What is the half-life of Kisspeptin-54 (Metastin)?
Reported half-life for Kisspeptin-54 (Metastin) is Short; study-dependent. Half-life describes how long the compound persists in circulation, not how long any effect lasts, and published figures vary with route of administration, formulation and the population studied.
Is Kisspeptin-54 (Metastin) banned in sport?
Kisspeptin-54 (Metastin) is recorded here as prohibited in sport. Athletes subject to anti-doping rules should check the current WADA Prohibited List directly, since it is revised annually and classifications change.
What peptides are similar to Kisspeptin-54 (Metastin)?
Compounds most often compared with Kisspeptin-54 (Metastin) include Kisspeptin-10, Gonadorelin, Cetrorelix and Degarelix. They are grouped by shared mechanism or research area rather than by equivalence, and their regulatory status and evidence base differ.
References
- WADA Prohibited List 2026External reference
- Circulatory metastin/kisspeptin-1 in polycystic ovary syndrome: a systematic review and meta-analysis with diagnostic test accuracy — Reprod Biomed Online, 2019External reference
- Safety Evaluation of KP-10 (Metastin 45-54) Following once Daily Intravenous Administration for 14 Days in Dog — Int J Toxicol, 2021External reference
- Kisspeptin receptor agonist has therapeutic potential for female reproductive disorders — J Clin Invest, 2020External reference
- Distribution of the kisspeptin system and its relation with gonadotropin-releasing hormone in the hypothalamus — Vitam Horm, 2025External reference
- Kisspeptin system-physiology and clinical perspectives — Ann Endocrinol (Paris), 2025External reference
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Compiled by Peptide Library Editorial · Reviewed Aug 30, 2026 · Updated Sep 6, 2026 · Version 2
This Kisspeptin-54 (Metastin) profile is compiled from published literature (5 cited studies linked above), public regulatory records and chemical registries. It describes what research reports; it is not medical advice, and nothing here is a dosing recommendation for humans. Peptide Library does not sell peptides. Editorial policy · How profiles are compiled · Report an error
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