cetrorelix acetate: clinical use

Prescribing considerations

• Restrict prescribing to specialists experienced in assisted reproduction.
• Give the first administration under medical supervision where severe hypersensitivity can be treated immediately.
• Assess active allergy or allergic predisposition; treatment is not advised in severe allergic conditions.
• Use caution in hepatic or renal impairment because these groups have not been adequately studied.
• Repeated stimulation cycles require individual benefit–risk assessment because experience is limited.

Contraindications and cautions

• Hypersensitivity to cetrorelix, structural GnRH analogues, extrinsic peptide hormones or an excipient
• Pregnancy
• Breastfeeding
• Severe renal impairment

Monitoring

• Observe for allergic or pseudo-allergic reactions, particularly with first exposure.
• Monitor ovarian response using follicular assessment and, where appropriate, circulating oestradiol.
• Assess promptly for symptoms and complications of ovarian hyperstimulation syndrome.

Clinical pharmacology

Cetrorelix is a competitive GnRH receptor antagonist that rapidly suppresses pituitary LH and FSH secretion without an initial stimulatory flare. It delays the LH surge and ovulation; the endocrine effect is reversible after withdrawal.

Formulation and product differences

• The product contains a powder vial and a pre-filled syringe of water for injections.
• The reconstituted solution must be clear and particle-free and used immediately.
• The powder contains mannitol, and the solvent is water for injections.