Cetrorelix (as acetate) 0.25 mg per vial

Basic Info

CAS Number	130143-01-0
Active Ingredient	Cetrorelix acetate, a synthetic GnRH-antagonist decapeptide
Dosage Form	Lyophilised powder for injection
Specification & Packaging	Strength: 0.25 mg per vial Pack: 1 vial + 1 mL diluent Group: 03 Item No.: 37

Storage & Common Excipients

Storage Conditions	2–8 °C, protected from light (for the unreconstituted lyophilised powder); follow the label
Common Excipients	Typical lyophilisate: mannitol (tonicity), sucrose; reconstituted with sterile water for injection. Confirm against COA

Product Introduction

A gonadotropin-releasing hormone antagonist that competitively blocks the GnRH receptor and rapidly suppresses LH and FSH secretion. The reference product is a powder for injection (0.25 mg/vial with 1 mL sterile water for reconstitution)

Therapeutic Use

Women undergoing controlled ovarian hyperstimulation for assisted reproduction (IVF/ICSI), to prevent premature LH surge and control timing of ovulation; indications follow the locally approved label

Mode of Action

A competitive GnRH-receptor antagonist with rapid onset (no receptor desensitisation required) and fully reversible suppression after withdrawal; shortens the treatment cycle compared with GnRH agonists; no oestrogenic effect

Administration & Monitoring

Subcutaneous injection once daily; monitor follicular development by transvaginal ultrasound, serum oestradiol and LH surge; observe for systemic or injection-site hypersensitivity after the first dose

Important Safety Information

Prescription medicine; contraindicated in hypersensitivity to the product or any excipient (including mannitol). Can contribute to ovarian hyperstimulation syndrome (OHSS), particularly when combined with gonadotropins. Preservative-free — use immediately after reconstitution

Adverse Reactions

Mild transient injection-site reactions (erythema, bruising, pain, induration); headache, nausea, vomiting, abdominal distension; ovarian hyperstimulation syndrome (OHSS); systemic hypersensitivity reactions (anaphylaxis reported rarely); transient transaminase elevation

Important Risks

OHSS (risk increased with concurrent gonadotropins); hypersensitivity (observation after the first dose); pregnancy — the product is used in reproductive treatment and is contraindicated in pregnancy

Contraindications

Hypersensitivity to cetrorelix or any excipient; pregnancy; lactation; unexplained vaginal bleeding; active hepatic or renal disease (relative); no paediatric or over-65 indication

Special Populations

Women of childbearing potential are the principal treatment population; no use in pregnancy or lactation; no paediatric, adolescent or geriatric indication; use with caution in hepatic or renal impairment

Usage Limitations

Prescription-only, used under specialist reproductive supervision; do not refrigerate after reconstitution and inject promptly; do not mix with other drugs in the same syringe; must be used with ultrasound and hormone monitoring

Anti-Doping Testing

Cetrorelix acetate is not on the WADA Prohibited List. However, it suppresses endogenous gonadotropins and can therefore **distort interpretation** of Athlete Biological Passport sex-hormone markers, so athletes should proactively declare its use

Product Quality Testing

Identification (peptide mapping/HPLC-MS), assay (peptide content), purity and single impurities, acetate content, water content, reconstitution time, clarity and sterility after reconstitution, endotoxin, fill volume, stability (including long-term 25 °C/60% RH); COA