Peptide LibraryCetrorelix
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
- Evidence level
- FDA Approved
- Human dose established
- Yes
- Administration Route
- Subcutaneous
- Frequency
- Once daily
- Last updated
- Nov 7, 2026
- Reviewed
- Nov 7, 2026
Research summary
GnRH receptor antagonist approved to prevent premature luteinising hormone surges in women undergoing controlled ovarian stimulation.
Research evidence
- Regulatory review (FDA label)1 reviewed source
- Controlled human trialsNone in reviewed sources
- Early or uncontrolled human studies1 reviewed source
- Lab & animal studiesNone in reviewed sources
How it works
Each step shows whether the sources Peptide Library has reviewed include that kind of research. Counts are reviewed sources, not every study ever published. Reviews and programme summaries that describe human use are shown as "reported", not as trials, and registered trials without published results are listed but not counted. A higher step means research has progressed further; it does not mean a compound works better or is safer. Compounds whose evidence has not been reviewed yet show "Not reviewed" instead of a guess.
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.
Cetrorelix dosage evidence
Cetrorelix has an FDA-approved human dosage for preventing a premature LH surge in women having controlled ovarian stimulation. The Cetrotide label dose is 0.25 mg under the skin once a day, started on stimulation day 5 or 6 and continued until the day of hCG.
| Human dosing established | Yes |
|---|---|
| Studied dose range | 0.25 mg once daily during ovarian stimulation, until the day of hCG |
| Route | Subcutaneous |
| Frequency | Once daily |
| Duration studied | From stimulation day 5 or 6 until the day of hCG |
| Evidence level | FDA Approved |
| Last reviewed | 2026-11-07 |
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 |
|---|---|---|---|---|---|---|---|
| FDA label — Cetrotide 0.25 mgFDA-approved label · FDA prescribing information | Women undergoing controlled ovarian stimulation | 0.25 mg | Subcutaneous | Once daily | From stimulation day 5 (morning or evening) or day 6 (morning) until the day of hCG administration | Inhibition of premature LH surges | CETROTIDE (cetrorelix acetate for injection) 0.25 mg — FDA prescribing information (EMD Serono), DailyMed |
| Cetrotide confirmatory trial (Mettler and Brandenburg, 2000)Clinical trial · Single-arm clinical trial | Women having ovarian stimulation with recombinant FSH for IVF or ICSI (n=26) | 0.25 mg | Subcutaneous | Once daily from cycle day 7 until the day of hCG | One stimulation cycle | Mean 5.5 oocytes retrieved in 24 patients; pregnancy in 10 patients | Mettler L, Brandenburg K. 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. 2000. |
Where sources disagree
- The Cetrotide label's clinical studies section also describes a single 3 mg dose regimen that was tested in phase 3, but its dosage section gives only the 0.25 mg daily regimen.
- Cetrorelix is one part of an IVF protocol: the label pairs it with gonadotropins from cycle day 2 or 3 and hCG to induce ovulation, and says no hCG should be given if the ovaries respond excessively.
- The label says pregnancy must be excluded before treatment and reports hypersensitivity reactions, including anaphylactoid reactions with the first dose.
Sequence & 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
Research statistics
759 PubMed publications · 46.1% human clinical research · 92 registered trials
Counts of published research through 2026-11-01, not evidence that it works. Publications by year, study types and trials · How publications are counted
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 |
How FDA approval, compounding and research-only status differ
Benefits
—
Cetrorelix side effects
No side effects listed yet for this entry.
Storage & stability
This compound is not supplied as a powder to be mixed, so the freeze-dried powder and reconstitution handling described for research peptides does not apply. Storage conditions are product-specific: follow the label or packaging of the product itself.
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 Nov 7, 2026 · Version 2
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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