Leuprolide
Also known as: Lupron, Eligard, Leuprorelin, GnRH agonist
Leuprolide (also called Lupron or Eligard) is an FDA-approved GnRH agonist. Leuprolide is a GnRH agonist with a D-leucine substitution at position six and an ethylamide C-terminus, changes that increase receptor affinity and greatly extend half-life relative to native GnRH.
For research use only.
Key Facts
- CAS
- 53714-56-0
- Molecular Weight (MW)
- 1209.4 g/mol (free base); 1269.4 g/mol (acetate)
- Half-life
- ~3 hours (immediate-release); depot provides sustained levels
- FDA status
- Approved
- Administration Route
- Subcutaneous / Intramuscular
- Frequency
- Daily, monthly, every 3 months, or every 4 months depending on formulation
- Last updated
- Aug 30, 2026
- Reviewed
- Aug 30, 2026
- Targets
- GnRH receptor
Research summary
FDA-approved GnRH agonist for prostate cancer, endometriosis, and central precocious puberty. Causes pituitary downregulation after an initial flare. WADA S2 (GnRH analogues).
Peptide Library's Leuprolide 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.
Protocol
- Dosage Range
- Varies by indication: 1 mg daily, 7.5 mg monthly, 22.5 mg every 3 months, or 30 mg every 4 months
- Frequency
- Daily, monthly, every 3 months, or every 4 months depending on formulation
- Cycle
- Long-term use as prescribed
- Administration Route
- Subcutaneous / Intramuscular
- Reconstitution Guide
- Depot formulations require reconstitution per package insert
- Injection Sites
- Per product labeling
- Concentration Example
- Depot: 7.5 mg, 22.5 mg, or 30 mg per injection
- Timing Notes
- Inject subcutaneously or intramuscularly as per formulation
- Expected Onset
- Hormonal suppression typically achieved within 2-4 weeks
May vary by vendor concentration and protocol.
Not yet checked against primary sources
These figures are compiled from earlier reference material. They have not been verified against FDA labelling, registered trials or published literature, no citation is attached to them, and none of them is a recommended dose. Leuprolide is queued for dosage evidence review.
Compare reported doses across the whole librarySequence & molecular data
| Molecular formula | C59H84N16O12 |
|---|---|
| Molecular weight | 1209.4 g/mol (free base); 1269.4 g/mol (acetate) |
| CAS number | 53714-56-0 |
| Half-life | ~3 hours (immediate-release); depot provides sustained levels |
| Appearance | Solution and depot formulations |
| Formulation | Lyophilized Powder |
| PubChem CID | 657181 |
| FDA UNII | EFY6W0M8TG |
| ChEMBL | CHEMBL1201199 |
| DrugBank | DB00007 |
Identifiers link to the public PubChem, FDA Substance Registration (UNII), ChEMBL and DrugBank records for the same entity.
Science
Mechanism of Action
Leuprolide is a GnRH agonist with a D-leucine substitution at position six and an ethylamide C-terminus, changes that increase receptor affinity and greatly extend half-life relative to native GnRH. Delivered continuously from a depot rather than in physiological pulses, it first stimulates the pituitary — the testosterone or oestrogen flare seen in the first one to two weeks — and then desensitises and downregulates the GnRH receptor. Gonadotropin secretion falls and sex steroid production drops to castrate concentrations within roughly two to four weeks. The initial flare is clinically relevant, which is why anti-androgen cover is used in advanced prostate cancer.
Origin
Synthetic nonapeptide GnRH analog.
Targets
Studies
- Treatment of High-Risk Biochemically Recurrent Prostate Cancer With Enzalutamide in Combination With Leuprolide: Secondary End Points From the EMBARK Trial
- Testosterone Recovery for Relugolix Versus Leuprolide in Men with Advanced Prostate Cancer: Results from the Phase 3 HERO Study
- Cardiovascular Safety of Degarelix Versus Leuprolide in Patients With Prostate Cancer: The Primary Results of the PRONOUNCE Randomized Trial
- Long-acting injectable PLGA/PLA depots for leuprolide acetate: successful translation from bench to clinic
- Improved Survival with Enzalutamide in Biochemically Recurrent Prostate Cancer
Regulatory & research status
Leuprolide is an FDA-approved product for specific labelled indications. Approval does not extend to the research contexts described on this page, and approved products are prescription medicines.
| FDA status | Approved |
|---|---|
| Availability | Prescription-Only |
| WADA (sport) | Banned in Sport |
| Library classification | FDA-Approved |
Benefits
Leuprolide side effects
Side Effects
- Hot flashes
- Bone loss
- Flare phenomenon
- Injection-site reactions
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.
Leuprolide: frequently asked questions
What is Leuprolide?
FDA-approved GnRH agonist for prostate cancer, endometriosis, and central precocious puberty. Causes pituitary downregulation after an initial flare. WADA S2 (GnRH analogues).
How does Leuprolide work?
Leuprolide is a GnRH agonist with a D-leucine substitution at position six and an ethylamide C-terminus, changes that increase receptor affinity and greatly extend half-life relative to native GnRH. Delivered continuously from a depot rather than in physiological pulses, it first stimulates the pituitary — the testosterone or oestrogen flare seen in the first one to two weeks — and then desensitises and downregulates the GnRH receptor.
Is Leuprolide FDA approved?
Yes. Leuprolide is approved by the FDA, and approved products are prescription medicines. Approval is always for specific indications studied in clinical trials, so an approved status does not mean the compound is approved for every use it is discussed for. Research-chemical material sold under the same name is not the approved product.
What is the half-life of Leuprolide?
Reported half-life for Leuprolide is ~3 hours (immediate-release); depot provides sustained levels. 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 Leuprolide banned in sport?
Leuprolide 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 Leuprolide?
Compounds most often compared with Leuprolide include Goserelin, Triptorelin, Nafarelin and Histrelin. They are grouped by shared mechanism or research area rather than by equivalence, and their regulatory status and evidence base differ.
References
- FDA label — Lupron DepotExternal reference
- WADA Prohibited List 2026External reference
- Treatment of High-Risk Biochemically Recurrent Prostate Cancer With Enzalutamide in Combination With Leuprolide: Secondary End Points From the EMBARK Trial — J Urol, 2026External reference
- Testosterone Recovery for Relugolix Versus Leuprolide in Men with Advanced Prostate Cancer: Results from the Phase 3 HERO Study — Eur Urol Oncol, 2024External reference
- Cardiovascular Safety of Degarelix Versus Leuprolide in Patients With Prostate Cancer: The Primary Results of the PRONOUNCE Randomized Trial — Circulation, 2021External reference
- Long-acting injectable PLGA/PLA depots for leuprolide acetate: successful translation from bench to clinic — Drug Deliv Transl Res, 2023External reference
- Improved Survival with Enzalutamide in Biochemically Recurrent Prostate Cancer — N Engl J Med, 2026External reference
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Compiled by Peptide Library Editorial · Reviewed Aug 30, 2026 · Updated Aug 30, 2026 · Version 1
This Leuprolide 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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