Cetrorelix
Cetrorelix is an FDA-approved GnRH receptor antagonist. Cetrorelix competitively blocks GnRH receptors on pituitary gonadotrophs, suppressing luteinising hormone secretion within hours and without the initial flare seen with agonists. In assisted reproduction this prevents premature ovulation while allowing follicles to continue developing under exogenous gonadotropin stimulation.
For research use only.
Key Facts
- CAS
- —
- Molecular Weight (MW)
- 1431 g/mol
- Half-life
- —
- FDA status
- Approved
- Administration Route
- subcutaneous
- Frequency
- —
- Last updated
- Aug 30, 2026
- Reviewed
- Aug 30, 2026
Research summary
GnRH receptor antagonist approved to prevent premature luteinising hormone surges in women undergoing controlled ovarian stimulation.
Peptide Library's Cetrorelix 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
- —
- Frequency
- —
- Cycle
- —
- Administration Route
- subcutaneous
- Reconstitution Guide
- —
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. Cetrorelix is queued for dosage evidence review.
Compare reported doses across the whole librarySequence & molecular data
| Molecular formula | C70H92ClN17O14 |
|---|---|
| Molecular weight | 1431 g/mol |
| PubChem CID | 25074887 |
| FDA UNII | OON1HFZ4BA |
| ChEMBL | CHEMBL1200490 |
| DrugBank | DB00050 |
Identifiers link to the public PubChem, FDA Substance Registration (UNII), ChEMBL and DrugBank records for the same entity.
Science
Mechanism of Action
Cetrorelix competitively blocks GnRH receptors on pituitary gonadotrophs, suppressing luteinising hormone secretion within hours and without the initial flare seen with agonists. In assisted reproduction this prevents premature ovulation while allowing follicles to continue developing under exogenous gonadotropin stimulation. The effect is dose-dependent and reverses on discontinuation.
Studies
- Efficacy of GnRH antagonists in the treatment of uterine fibroids: a meta-analysis
- Cetrotide confirmatory trial of cetrorelix/0.25 mg in 26 women undergoing ovarian stimulation with recombinant follicle stimulating hormones for IVF, ICSI and embryo transfer (ET)
- Delayed Start Versus Conventional GnRH Antagonist Protocol in Poor Responders Pretreated With Estradiol in Luteal Phase: A Randomized Controlled Trial
- Cetrorelix in reproductive medicine
- The LHRH antagonist cetrorelix: a review
Regulatory & research status
Cetrorelix 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 |
|---|---|
| Research status | Approved product (see FDA status) |
| Availability | Prescription-Only |
| WADA (sport) | Unknown / Not Listed |
| Library classification | FDA-Approved |
Benefits
—
Potential Side Effects
No side effects listed yet for this entry.
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.
Cetrorelix: frequently asked questions
What is Cetrorelix?
GnRH receptor antagonist approved to prevent premature luteinising hormone surges in women undergoing controlled ovarian stimulation.
How does Cetrorelix work?
Cetrorelix competitively blocks GnRH receptors on pituitary gonadotrophs, suppressing luteinising hormone secretion within hours and without the initial flare seen with agonists. In assisted reproduction this prevents premature ovulation while allowing follicles to continue developing under exogenous gonadotropin stimulation.
Is Cetrorelix FDA approved?
Yes. Cetrorelix 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 peptides are similar to Cetrorelix?
Compounds most often compared with Cetrorelix include Degarelix, Ganirelix, Leuprolide and Gonadorelin. They are grouped by shared mechanism or research area rather than by equivalence, and their regulatory status and evidence base differ.
References
- Efficacy of GnRH antagonists in the treatment of uterine fibroids: a meta-analysis — Arch Gynecol Obstet, 2025External reference
- Cetrotide confirmatory trial of cetrorelix/0.25 mg in 26 women undergoing ovarian stimulation with recombinant follicle stimulating hormones for IVF, ICSI and embryo transfer (ET) — Clin Exp Obstet Gynecol, 2000External reference
- Delayed Start Versus Conventional GnRH Antagonist Protocol in Poor Responders Pretreated With Estradiol in Luteal Phase: A Randomized Controlled Trial — Reprod Sci, 2015External reference
- Cetrorelix in reproductive medicine — F S Rep, 2023External reference
- The LHRH antagonist cetrorelix: a review — Hum Reprod Update, 2000External reference
Related research, comparisons & guides
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Compiled by Peptide Library Editorial · Reviewed Aug 30, 2026 · Updated Aug 30, 2026 · Version 1
This Cetrorelix 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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