# Kisspeptin Dosing Parameters — Research-Context Summary of Administration in Registered Clinical Trials > Research-context summary of kisspeptin administration parameters from registered clinical trials: dose ranges for KP-10 and KP-54, half-life data, routes studied, and receptor desensitization considerations. Dose ranges, routes, half-life data, and desensitization considerations — drawn exclusively from peer-reviewed registered protocols. This page is research context, not dosing guidance. ## The short version Kisspeptin-10 and kisspeptin-54 are two forms derived from the same gene. They both activate the same receptor, produce comparable hormonal responses at matched molar doses, but differ sharply in how long they last — about 4 minutes for kisspeptin-10 versus 27 to 28 minutes for kisspeptin-54. That half-life gap matters: the shorter form clears via plasma peptidases before it can sustain the hormonal response that the longer form extends. That difference drives the choice of route and protocol in the clinical trials. This page documents what those registered protocols actually administered: IV infusion ranges for reproductive hormone restoration and sexual desire studies, subcutaneous bolus doses for IVF egg-maturation triggering, and the intranasal dose first demonstrated effective in 2025. None of these are recommendations. They are the administration parameters the research record reports, with their sources cited. ## Isoform distinction and molecular context Kisspeptin research has primarily studied two isoforms: kisspeptin-10 (KP-10, 1,302.5 Da, 10 amino acids) and kisspeptin-54 (KP-54, approximately 6,264 Da, 54 amino acids). Both share the identical C-terminal RF-amide sequence required for KISS1R binding and biological activity. In a direct head-to-head comparison in healthy men, both isoforms produced comparable LH and FSH area-under-the-curve responses at equivalent molar doses (0.1, 0.3, and 1.0 nmol/kg/h IV over 3 hours), despite their substantially different molecular masses and plasma pharmacokinetics [3]. The principal practical distinction between isoforms is half-life. After intravenous bolus administration in humans, kisspeptin-10 has a plasma half-life of approximately 4 minutes (3.8 ± 0.3 min in men; 4.1 ± 0.4 min in follicular-phase women). Clearance occurs primarily via matrix metalloproteinases (MMP-2, MMP-9) and plasma peptidases, with renal clearance also contributing given the low molecular weight. Kisspeptin-54's plasma half-life after IV bolus is approximately 27–28 minutes — longer due to the greater peptide length conferring partial protease resistance [3]. This half-life difference has direct implications for the route and frequency of administration in clinical protocols. For effects requiring sustained plasma concentrations — reproductive hormone restoration, HSDD studies, bone formation measurement — continuous IV infusion is the standard approach. For applications requiring a single triggered event — oocyte maturation in IVF — a subcutaneous bolus of kisspeptin-54, which provides a more extended concentration profile than KP-10 would at the same molar dose, has been the primary approach studied. ## Intravenous infusion: doses studied in registered protocols The intravenous route has been used in the large majority of registered kisspeptin clinical trials. Doses and durations vary by indication: **Reproductive hormone restoration / hypothalamic amenorrhea:** The range studied in the 2014 Jayasena et al. trial was 0.01–1.00 nmol/kg/h of kisspeptin-54, administered as a continuous IV infusion over 8–10 hours. At intermediate doses, a 3-fold increase in LH pulse number and 6-fold increase in pulse secretory mass were observed. At the highest dose tested (1.00 nmol/kg/h), desensitization — blunting of the LH response — was observed, consistent with KISS1R internalization under sustained agonism [2]. **First proof-of-concept (healthy men, Dhillo et al. 2005):** Dose range 0.25–12 pmol/kg/min as a 90-minute IV infusion. Dose-dependent LH elevation was observed across this range; the study used this range to establish the first human dose-response curve for kisspeptin-54 [1]. **Head-to-head isoform comparison (healthy men):** 0.1, 0.3, and 1.0 nmol/kg/h of either kisspeptin-10 or kisspeptin-54, IV over 3 hours. Comparable LH and FSH responses at each dose level; GnRH at equivalent doses produced approximately 2–3× higher LH and approximately 2× higher FSH responses [3]. **HSDD studies (men and women):** 1 nmol/kg/h IV infusion over 75 minutes. This dose was selected based on established gonadotropin response curves and was administered as a fixed rate across the infusion window. No adverse effects were recorded in either the male [6] or female [7] trials at this dose. **Bone formation study (healthy men, Comninos et al. 2022):** 1 nmol/kg/h IV for 90 minutes. Bone formation markers (osteocalcin) were measured at intervals over 240 minutes post-infusion [8]. **Safety / anxiety study (2025, largest RCT, n=95):** 1 nmol/kg/h IV over 75 minutes. No anxiogenic effects, no changes in cortisol, blood pressure, or heart rate. ## Subcutaneous administration: IVF trigger protocols Subcutaneous kisspeptin-54 bolus injection has been studied specifically as an oocyte maturation trigger in IVF protocols for patients at high risk of ovarian hyperstimulation syndrome (OHSS). In the Phase 2 Abbara et al. trial (2015), four dose levels were tested: 3.2, 6.4, 9.6, and 12.8 nmol/kg. The 12.8 nmol/kg dose produced oocyte maturation in 95% of high-OHSS-risk patients, with 0% moderate, severe, or critical OHSS, a 53% clinical pregnancy rate, and a 45% live birth rate per transfer [4]. A follow-up randomized trial tested the effect of a second kisspeptin-54 dose. A second subcutaneous injection of 9.6 nmol/kg administered 10 hours after the first trigger dose increased the proportion of patients achieving ≥60% mature oocyte yield from 45% (single dose) to 71% (double dose). OHSS incidence remained low: 0% moderate OHSS in the double-dose arm versus 3.2% in the single-dose arm [5]. The subcutaneous route for kisspeptin-54 has not been studied outside of the IVF triggering context in the registered published literature. The bioavailability, pharmacokinetics, and gonadotropin response profile for subcutaneous kisspeptin-54 in other clinical contexts have not been formally characterized in peer-reviewed human data. ## Intranasal delivery: 2025 first-in-humans demonstration The non-invasive intranasal route for kisspeptin was first demonstrated effective in humans in a 2025 study published in eBioMedicine (The Lancet group), authored by an Imperial College London / INSERM collaboration. In healthy men, intranasal kisspeptin-54 at 12.8 nmol/kg produced a mean LH increase of 4.4 ± 0.6 IU/L (p=0.002 versus placebo). The same preparation produced LH responses in healthy women and in women with hypothalamic amenorrhea. Dose levels studied ranged from 3.2 to 25.6 nmol/kg; 12.8 nmol/kg was the identified optimal dose. The nasal spray formulation was characterized for stability: it retained gonadotropin-stimulating activity after 60 days of storage at 4°C, an important practical parameter for any clinical translation. No adverse events were reported across all groups and dose levels. This study represents an early-phase (Phase 1-equivalent) characterization of the intranasal route. Long-term formulation stability, bioavailability variability between individuals, and effects in pathological states (hypothalamic amenorrhea, HSDD) via the intranasal route require further investigation before this route can be assessed against IV or SC administration for any specific indication. ## Receptor desensitization and the therapeutic window A critical pharmacodynamic consideration across all kisspeptin dosing contexts is receptor desensitization. At the highest dose tested in the hypothalamic amenorrhea trial (1.00 nmol/kg/h), LH response was blunted relative to intermediate doses — a pattern consistent with KISS1R internalization and downregulation under sustained agonism [2]. This mirrors the known pharmacology of GnRH agonists, which initially stimulate the HPG axis but cause profound hypogonadism after continuous administration. The implication is that pulsatile or intermittent dosing regimens may sustain HPG axis activation more effectively than continuous infusion, and that the optimal dose is not simply the highest tolerated dose but one that maintains receptor responsiveness across the dosing interval. The registered clinical protocols have not yet published definitive pulsatile-dosing schedules for kisspeptin in humans — this remains an active area of investigation. Kisspeptin is listed under the WADA Prohibited List S2 (Peptide Hormones, Growth Factors, Related Substances and Mimetics) as a compound with the potential to affect gonadotropin secretion and testosterone levels. Individuals subject to anti-doping regulations should be aware of this classification. No regulatory agency has approved kisspeptin for any human therapeutic indication; all documented human use is within registered clinical trials conducted under ethical review. --- An independent editorial digest of the peer-reviewed kisspeptin research record — no clinical advice, no product affiliation.