Cetrorelix Acetate

Gonadotropin-releasing hormone (GnRH) antagonist; a synthetic decapeptide analog of naturally occurring GnRH.1 2 3 4

Contraindications

• Known hypersensitivity to cetrorelix acetate, mannitol, or any ingredient in the formulation.1

• Known hypersensitivity to extrinsic peptide hormones, GnRH, or any other GnRH analog.1

• Severe renal impairment.a b

• Known or suspected pregnancy or lactation.1 b (See Fetal/Neonatal Morbidity and Mortality under Cautions.)

Warnings/Precautions

Warnings

May cause fetal harm; embryolethality reported in animals.a Congenital anomalies reported in women who received cetrorelix during pregnancy.1

Exclude pregnancy prior to initiation of therapy.1

Sensitivity Reactions

Severe anaphylaxis associated with cough, rash, and hypotension during therapy exceeding recommended dosages (10 mg daily for 7 months for an indication other than infertility) reported.1 Monitor patients carefully after initial injection.1 5 Take special care in women with signs and symptoms of active allergic conditions or history of allergies.a Use not recommended in women with severe allergic conditions.a

General Precautions

Elevations in liver function test results including ALT, AST, γ-glutamyltransferase (GGT, γ-glutamyl transpeptidase, GGTP), and alkaline phosphatase reported.1

Specific Populations

Category X.1 May result in fetal loss secondary to antigonadotropic properties.1 (See Contraindications and also see Fetal/Neonatal Morbidity and Mortality under Cautions.)

Not known whether cetrorelix is distributed into milk.1 Use not recommended.1

Not intended for use in pediatric patients.5

Not intended for use in patients ≥65 years of age.1

Common Adverse Effects

Ovarian hyperstimulation syndrome,1 2 3 4 nausea,1 headache.1

Absorption

Bioavailability

Absolute bioavailability in healthy females is 85%.1

Onset

Single 3-mg dose: Suppression of LH secretion within 1 hour.1

Single 0.25-mg dose: Suppression of LH secretion within 2 hours.1

Duration

Single 3-mg dose: LH secretion suppressed for ≥4 days.1

Single 0.25-mg dose: LH secretion suppressed for 24 hours.1

Distribution

Extent

Distributes into follicular fluid; similar concentrations in follicular fluid and plasma on day of oocyte retrieval.1

Not known whether cetrorelix is distributed into milk.1

Plasma Protein Binding

86%.1

Elimination

Metabolism

Metabolized by peptidases to smaller peptides.1

Elimination Route

In 24 hours, excreted in urine as unchanged drug (2–4%) and in bile (5–10%) as unchanged drug and metabolites.1

Half-life

Single 0.25-mg dose: 5 hours.1

Multiple 0.25-mg doses: 20.6 hours.1

Single 3-mg dose: 62.8 hours.1

Storage

Parenteral

0.25-mg vial: 2–8°C; store vials in carton to protect from light until used.1 b

3-mg vial: 25°C (may be exposed to 15–30°C); protect from excessive moisture and heat.1 b Store vials in carton to protect from light until used.1 b

• Importance of providing patient a copy of manufacturer’s patient information.1

• Importance of informing clinicians of a history of severe allergic reactions prior to initiation of therapy.b

• Importance of discussing duration of treatment and required monitoring procedures.1

• Importance of contacting a clinician immediately if prescribed dosage is exceeded.b

• Importance of advising women of risk of fetal harm if administered during pregnancy;1 need for pregnancy testing prior to initiation of therapy. Importance of women informing their clinician if they plan to breast-feed.a

• Importance of informing clinicians of existing or contemplated concomitant therapy, including prescription and OTC drugs.1

• Importance of informing patients of other precautionary information.1 (See Cautions.)