Product Overview

Leuprolide acetate (leuprorelin, CAS 74381-53-6) is a synthetic nonapeptide GnRH/LHRH agonist — the des-Gly¹⁰-[D-Leu⁶]-LH-RH N-ethylamide analog — with sequence Glp-His-Trp-Ser-Tyr-D-Leu-Leu-Arg-Pro-NHEt. It is supplied as the lyophilized acetate salt (free base C₅₉H₈₄N₁₆O₁₂, MW 1209.4; acetate salt C₆₁H₈₈N₁₆O₁₄, MW 1269.45). As a GnRH receptor agonist, leuprolide binds the pituitary GnRH receptor with high affinity and, after an initial “flare-up” — a transient surge of LH, FSH, and gonadal sex steroids lasting roughly one to two weeks — triggers receptor desensitization and downregulation, producing sustained suppression of LH, FSH, and sex steroids (chemical castration). This biphasic pharmacology is the mechanistic foundation of hormone-dependent oncology and endocrine research. Leuprolide is the active ingredient of the clinically established product Lupron®, referenced here strictly as RUO research context only — not as an endorsement or clinical claim.

As a research grade peptide supplier, UPOR Biotech provides leuprolide acetate for hormone-sensitive prostate cancer research, endometriosis and uterine fibroid studies, central precocious puberty models, IVF and controlled ovarian stimulation protocols, and hypothalamic-pituitary-gonadal (HPGA) axis pharmacology. The compound’s sustained sex-steroid suppression profile makes it a cornerstone reagent for studying androgen- and estrogen-dependent signaling in vitro and in vivo. Research Use Only (RUO) — not for human diagnostic or therapeutic use. Every batch is manufactured under ISO 9001, cGMP, and FDA facility registration with full documentation (COA, HPLC, MS, endotoxin), and is supplied lyophilized in 1/5/10/50 mg vials for convenient reconstitution.

Leuprolide vs Cetrorelix — GnRH Agonist (Flare-Up) vs GnRH Antagonist (No Flare-Up)

When comparing leuprolide (GnRH agonist) vs cetrorelix (GnRH antagonist), the defining mechanistic distinction is the flare-up profile. Leuprolide initially binds and stimulates the GnRH receptor, causing a transient surge of LH/FSH and sex steroids before receptor desensitization and downregulation achieve sustained suppression. Cetrorelix blocks the GnRH receptor directly, delivering immediate suppression with no flare-up — a critical difference for fertility protocols where premature ovulation must be prevented instantly, and for hormone-sensitive cancer research where a transient steroid surge can stimulate tumor growth. This agonist vs antagonist choice is central to experimental design in HPGA pharmacology, assisted reproduction, and hormone-dependent oncology studies.

Technical Specifications

PropertySpecification
Product NameLeuprolide Acetate — Research Grade (RUO) — GnRH Agonist Peptide
SynonymsLeuprolide; Leuprorelin; A-43818
Analog Typedes-Gly¹⁰-[D-Leu⁶]-LH-RH N-ethylamide analog of native luteinizing hormone-releasing hormone
CAS Number74381-53-6
Molecular FormulaC₆₁H₈₈N₁₆O₁₄ (acetate salt) / C₅₉H₈₄N₁₆O₁₂ (free base)
Molecular Weight1269.45 g/mol (acetate salt) / 1209.4 g/mol (free base)
Salt FormAcetate
Peptide ClassNonapeptide GnRH/LHRH agonist
SequenceGlp-His-Trp-Ser-Tyr-D-Leu-Leu-Arg-Pro-NHEt
C-Terminal ModificationN-ethylamide — enhanced metabolic stability and receptor potency vs native LH-RH
MechanismGnRH receptor agonist → initial flare-up → receptor desensitization and downregulation → sustained LH/FSH and sex-steroid suppression
Purity (HPLC)≥98.0% (area normalization)
Peptide Content≥85% (by nitrogen determination)
AppearanceWhite to off-white lyophilized powder
SolubilitySoluble in water, normal saline, and aqueous buffers at >10 mg/mL; freely soluble in methanol; sparingly soluble in ethanol
ReconstitutionReconstitute in sterile water or PBS; vortex gently to dissolve; aliquot to avoid repeated freeze-thaw
Endotoxin≤1.0 EU/mg
Water Content≤5.0% (Karl Fischer)
Counter-ionAcetate
pH3.0 – 6.0 (1 mg/mL aqueous solution)
Heavy Metals≤10 ppm
Storage−20°C, tightly sealed, protected from light and moisture
GradeResearch Grade (RUO)
ApplicationsHormone-sensitive prostate cancer research, endometriosis and uterine fibroid studies, central precocious puberty research, IVF protocols, HPGA axis pharmacology
CertificationsISO 9001, cGMP, FDA facility registration
Packaging1 mg / 5 mg / 10 mg / 50 mg sealed vials (lyophilized)
Shelf Life2 years (stored at −20°C)
DisclaimerResearch Use Only (RUO) — not for human diagnostic or therapeutic use

Key Benefits — Leuprolide Acetate

Potent GnRH Receptor Agonism — des-Gly¹⁰-[D-Leu⁶] Analog

Leuprolide binds the pituitary GnRH receptor with high affinity as a synthetic nonapeptide agonist. The D-Leu at position 6 and N-ethylamide C-terminal modification confer resistance to enzymatic degradation and enhanced receptor potency relative to native LH-RH.

GnRH Receptor Agonist

Sustained Sex-Steroid Suppression

Following the initial flare-up, chronic agonist exposure induces receptor desensitization and downregulation, producing sustained suppression of LH, FSH, and gonadal sex steroids — the biochemical basis of chemical castration in hormone-dependent research.

LH/FSH Suppression

Stable Acetate Salt Lyophilized Form

Supplied as the lyophilized acetate salt (C₆₁H₈₈N₁₆O₁₄, MW 1269.45), leuprolide offers excellent stability, aqueous solubility, and lot-to-lot consistency — enabling reproducible reconstitution and dependable experimental outcomes.

Lyophilized Acetate

≥98% HPLC Purity Research Peptide

Every lot is released at ≥98.0% purity by HPLC with ≤1.0 EU/mg endotoxin, ≥85% peptide content, and complete COA documentation — supporting rigorous, reproducible bioactivity and pharmacology studies.

≥98% HPLC

Applications

Hormone-Sensitive Prostate Cancer Research

Leuprolide-induced chemical castration models are central to studying androgen-dependent prostate cancer growth, androgen receptor signaling, and castration-resistant progression in preclinical oncology research. RUO reference only.

Endometriosis & Uterine Fibroid Studies

Sustained suppression of estrogen and progesterone supports in vivo models of endometriosis lesion regression and uterine leiomyoma (fibroid) growth inhibition — key platforms for gynecological therapeutic development.

Central Precocious Puberty Research

GnRH agonist-mediated HPGA suppression is the reference mechanism for puberty onset regulation studies, modeling the therapeutic paradigm used in central precocious puberty research.

IVF & Controlled Ovarian Stimulation Protocols

Pituitary desensitization with leuprolide enables programmed ovulation timing and multiple follicle development in controlled ovarian hyperstimulation (COH) research protocols.

Hypothalamic-Pituitary-Gonadal Axis Pharmacology

As a prototypical GnRH agonist, leuprolide is a reference reagent for HPGA feedback loop, gonadotropin secretion, and sex-steroid negative feedback investigations.

Peptide Reference Standard & Assay Development

High-purity leuprolide acetate serves as a reference standard for HPLC, LC-MS, and immunoassay development and validation in peptide analysis laboratories.

Frequently Asked Questions

Leuprolide acetate (leuprorelin, CAS 74381-53-6) is a synthetic nonapeptide GnRH/LHRH agonist — the des-Gly¹⁰-[D-Leu⁶]-LH-RH N-ethylamide analog, sequence Glp-His-Trp-Ser-Tyr-D-Leu-Leu-Arg-Pro-NHEt. It works by binding the pituitary GnRH receptor: after an initial flare-up (transient surge of LH/FSH and sex steroids), chronic stimulation causes receptor desensitization and downregulation, leading to sustained suppression of LH, FSH, and gonadal sex steroids — the basis of chemical castration in hormone-dependent research. Supplied as the lyophilized acetate salt, C₆₁H₈₈N₁₆O₁₄, MW 1269.45. Research Use Only (RUO).

Leuprolide is a GnRH agonist — it initially binds and stimulates the GnRH receptor, producing a transient flare-up of LH/FSH and sex steroids before receptor desensitization and downregulation achieve sustained suppression. Cetrorelix is a GnRH antagonist — it blocks the GnRH receptor directly for immediate suppression with no flare-up. This distinction is central to fertility research (immediate blockade vs programmed desensitization) and to hormone-sensitive cancer research where a transient steroid surge can stimulate tumor growth.

Leuprolide acetate is used in hormone-sensitive prostate cancer research (chemical castration models), endometriosis and uterine fibroid studies, central precocious puberty research, IVF and controlled ovarian stimulation protocols, hypothalamic-pituitary-gonadal (HPGA) axis pharmacology, and as a peptide reference standard for HPLC, LC-MS, and immunoassay development.

Store lyophilized leuprolide acetate at −20°C, tightly sealed and protected from light and moisture. Reconstitute in sterile water or a compatible buffer (PBS or physiological saline) at the desired concentration, vortexing gently until fully dissolved. To preserve stability, aliquot and store reconstituted solution at −20°C or −80°C and avoid repeated freeze-thaw cycles.

Every shipment includes a COA (HPLC purity ≥98.0%, peptide content, counter-ion), MSDS, HPLC chromatogram, mass spectrometry (MS) confirmation, endotoxin test (≤1.0 EU/mg), heavy metals analysis, and stability data. Manufacturing is conducted under ISO 9001, cGMP, and FDA facility registration. Leuprolide acetate is supplied for Research Use Only (RUO) — not for human diagnostic or therapeutic use.