Head-to-head clinical analysis & difference comparison: details on mechanism of action, dosing, half-life, interactions, and maternal-fetal safety.
CETRORELIX ACETATE vs DEGARELIX ACETATE
Clinician-reviewed, head-to-head comparison of mechanism, dosing, pharmacokinetics, and safety profiles.
Last clinically reviewed: July 2026 · OpiCalc Medical Review Team
Gonadotropin-releasing hormone (Gn RH) antagonist. Competitively blocks Gn RH receptors on pituitary gonadotropes, inhibiting secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).
Gonadotropin-releasing hormone (Gn RH) receptor antagonist; competitively and reversibly binds to Gn RH receptors in the anterior pituitary, rapidly suppressing luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion, thereby reducing testosterone production.
Inhibition of premature LH surges in women undergoing controlled ovarian hyperstimulation for assisted reproductive technology (ART)
Treatment of advanced prostate cancer
250 mcg subcutaneously once daily, starting on day 7 of ovarian stimulation and continuing until the day of h CG administration. Alternatively, a single 3 mg subcutaneous dose on day 7 of stimulation if h CG is given on day 9.
Subcutaneous injection: 240 mg loading dose (two 120 mg injections) on day 1, followed by 80 mg every 28 days.
Terminal elimination half-life: ~7-9 hours in healthy adults; prolonged to ~14-30 hours in patients with hepatic or renal impairment (clinical significance: no dose adjustment needed for mild-to-moderate renal or hepatic impairment, but caution in severe cases due to potential accumulation).
Terminal elimination half-life is approximately 43-73 days after subcutaneous administration, reflecting slow release from the depot formulation.
Metabolized via peptidolysis; not significantly metabolized by cytochrome P450 enzymes.
Hepatic via hydrolysis of the acetate ester; no significant CYP450 involvement.
Primarily renal (excreted unchanged in urine ~42% within 24 hours; total urinary recovery ~66-69% over 8 days); biliary/fecal elimination accounts for <5%.
Renal elimination accounts for approximately 20-30% of the dose as unchanged drug; fecal elimination accounts for 70-80% primarily as metabolites.
86-96% bound to albumin (alpha-1-acid glycoprotein binding not significant).
Approximately 90% bound to plasma proteins, primarily albumin and alpha-1-acid glycoprotein.
Apparent Vd: 1.14 L/kg (range 0.8–1.4 L/kg), indicating distribution primarily into extracellular fluid; not extensively tissue-bound.
Approximately 1 L/kg, indicating extensive distribution into tissues.
Subcutaneous: ~85% (absolute bioavailability).
Subcutaneous: approximately 100% for the depot formulation; not available orally due to peptide degradation.
No dose adjustment required for mild to moderate renal impairment (GFR ≥30 m L/min). Insufficient data for severe impairment (GFR <30 m L/min); use with caution.
No dose adjustment required for GFR ≥15 m L/min. Insufficient data for GFR <15 m L/min or dialysis; use caution.
No dose adjustment recommended for mild to moderate hepatic impairment (Child-Pugh A or B). Not studied in severe impairment (Child-Pugh C); use with caution.
No dose adjustment required for mild to moderate hepatic impairment (Child-Pugh A or B). Not studied in severe impairment (Child-Pugh C).
Not indicated in pediatric patients (safety and efficacy not established).
Safety and efficacy not established in pediatric patients; no recommended dosing.
No specific dose adjustment; limited experience in women >65 years. Use with caution due to reduced renal and hepatic function.
No specific dose adjustment required; similar efficacy and safety observed in elderly patients (≥65 years) compared to younger adults.
None.
None
Hypersensitivity reactions including anaphylaxis and urticaria.,Ovarian hyperstimulation syndrome (OHSS) due to gonadotropin therapy.,Pregnancy category X: contraindicated in pregnancy.,May cause fetal harm if administered during pregnancy.
Hypersensitivity reactions including anaphylaxis and angioedema,QT interval prolongation,Laboratory test interference with gonadotropin and gonadal steroid assays,Injection site reactions including pain and erythema,Bone density loss,Hyperglycemia and increased risk of diabetes
Hypersensitivity to cetrorelix acetate, mannitol, or any component.,Pregnancy and lactation.,Postmenopausal women.,Severe hepatic or renal impairment (safety not established).
Hypersensitivity to degarelix or any component of the formulation,Pregnancy (potential fetal harm)
No significant food interactions. No dietary restrictions required.
No specific food interactions have been identified. Degarelix is administered parenterally and does not interact with dietary components. Avoid grapefruit juice if concurrent QT-prolonging drugs are used, but not a direct interaction with degarelix.
Category X. Risk of congenital anomalies if pregnancy occurs. Avoid use during pregnancy; confirm negative pregnancy test before initiation. First trimester: No data; theoretical risk due to hormonal antagonism. Second and third trimesters: Not indicated for use; may interfere with pregnancy maintenance.
Category X: Contraindicated in pregnancy. First trimester: Risk of spontaneous abortion and congenital anomalies due to hormonal disruption. Second and third trimesters: Potential for fetal androgen deprivation leading to ambiguous genitalia in male fetuses.
Not recommended during breastfeeding. M/P ratio unknown; cetrorelix is likely excreted in milk based on molecular weight; potential for adverse effects in the infant, including hormonal disruption.
No data available on excretion in human milk; potential for serious adverse effects in nursing infants; discontinue breastfeeding or discontinue drug.
Contraindicated in pregnancy; no dose adjustment recommended. Use only in non-pregnant patients. Pharmacokinetic changes in pregnancy unknown; drug not intended for use during gestation.
No dose adjustments are applicable as degarelix is contraindicated in pregnancy; therapy must be discontinued if pregnancy occurs.
Administer subcutaneously in the lower abdominal wall. Rotate injection sites. Reconstitute with 1 m L of sterile water for injection or provided diluent; use immediately after reconstitution. Monitor for ovarian hyperstimulation syndrome (OHSS), especially in patients with polycystic ovary syndrome. Cetrorelix can cause transient injection site reactions. It is contraindicated in pregnancy and during lactation.
Degarelix acetate is a Gn RH antagonist used for advanced prostate cancer. It provides rapid testosterone suppression without the initial testosterone surge seen with Gn RH agonists. Monitor serum testosterone and PSA levels; castrate levels (<50 ng/d L) typically achieved within 3 days. Injection site reactions are common; rotate injection sites (abdomen, thigh, buttock). Avoid in patients with known QT prolongation or concurrent QT-prolonging drugs. Contraindicated in women and children.
Cetrorelix is used to prevent premature ovulation during fertility treatments.,Inject the medication exactly as prescribed, usually once daily in the abdomen.,Rotate injection sites and do not inject into irritated or bruised skin.,Do not skip doses; if a dose is missed, contact your healthcare provider.,Report any symptoms of OHSS such as severe pelvic pain, nausea, vomiting, or sudden weight gain.,This drug is not for use during pregnancy; inform your doctor if you think you are pregnant.
Degarelix is given as a subcutaneous injection by a healthcare provider every month (or every 2 months for maintenance dose) to treat advanced prostate cancer.,Do not miss scheduled injections because consistent dosing is needed to keep testosterone levels low.,Common side effects include injection site pain, redness, or swelling; hot flashes; increased liver enzymes; and weight gain.,Report signs of allergic reaction (rash, itching, difficulty breathing) or prolonged QT interval (fainting, palpitations) to your doctor immediately.,Degarelix may cause bone thinning; discuss calcium and vitamin D supplementation with your doctor.,This drug can cause harm to a fetus; not for use in women or children.
No interactions on record
"Asenapine, a second-generation antipsychotic, is associated with dose-dependent QTc interval prolongation due to its inhibitory effects on cardiac potassium channels (specifically IKr). Degarelix, a GnRH antagonist used in prostate cancer, may also cause QTc prolongation, likely through hormonal suppression mechanisms. Coadministration can result in additive QTc prolongation, increasing the risk of torsade de pointes and other ventricular arrhythmias, especially in patients with pre-existing risk factors."
"Dolasetron, a 5-HT3 receptor antagonist, is known to cause dose-dependent prolongation of the QT interval by blocking cardiac potassium channels. When coadministered with Degarelix, a GnRH receptor antagonist that also reduces testosterone levels and can induce QT prolongation via electrolyte disturbances (e.g., hypokalemia, hypomagnesemia) or direct cardiac effects, the risk of additive QT prolongation is increased. This may lead to a higher propensity for torsade de pointes and other ventricular arrhythmias, particularly in patients with pre-existing risk factors."
"Cabazitaxel is a taxane antineoplastic agent that undergoes extensive hepatic metabolism via CYP3A4/5 and is a substrate of P-glycoprotein. Degarelix, a GnRH antagonist, has no known direct metabolic interaction with Cabazitaxel but may theoretically increase the risk of QT prolongation when combined with other drugs. However, the baseline description is vague; the interaction is not well-established and possibly refers to additive myelosuppression or cardiovascular effects from overlapping toxicities."
Explore head-to-head clinical comparisons of other medications in the same therapeutic classes.
Common clinical questions about CETRORELIX ACETATE vs DEGARELIX ACETATE, answered by our medical review team.
CETRORELIX ACETATE is a GnRH antagonist that works by Gonadotropin-releasing hormone (Gn RH) antagonist. Competitively blocks Gn RH receptors on pituitary gonadotropes, inhibiting secretion of luteinizing hormone (LH) and follicle-stimulating hormone (FSH).. DEGARELIX ACETATE is a GnRH antagonist that works by Gonadotropin-releasing hormone (Gn RH) receptor antagonist; competitively and reversibly binds to Gn RH receptors in the anterior pituitary, rapidly suppressing luteinizing hormone (LH) and follicle-stimulating hormone (FSH) secretion, thereby reducing testosterone production.. They differ in pharmacokinetic profiles, FDA-approved indications, and side effect profiles.
Potency comparisons between CETRORELIX ACETATE and DEGARELIX ACETATE depend on the specific clinical indication. These are both GnRH antagonist agents and are not directly interchangeable by dose. A physician or clinical pharmacist should guide any therapeutic switching decisions.
The standard adult dose of CETRORELIX ACETATE is: 250 mcg subcutaneously once daily, starting on day 7 of ovarian stimulation and continuing until the day of h CG administration. Alternatively, a single 3 mg subcutaneous dose on day 7 of stimulation if h CG is given on day 9.. The standard adult dose of DEGARELIX ACETATE is: Subcutaneous injection: 240 mg loading dose (two 120 mg injections) on day 1, followed by 80 mg every 28 days.. Dosing should always be individualized based on indication, renal and hepatic function, age, and other patient factors.
No direct drug-drug interaction has been formally documented between CETRORELIX ACETATE and DEGARELIX ACETATE in current clinical databases. However, individual patient risk factors including other medications, organ function, and comorbidities should always be evaluated by a qualified healthcare provider.
The maternal-fetal safety profiles differ. CETRORELIX ACETATE is classified as Category C. Category X. Risk of congenital anomalies if pregnancy occurs. Avoid use during pregnancy; confirm negative pregnancy test before initiation. First trimester: No data; theoretical r. DEGARELIX ACETATE is classified as Category C. Category X: Contraindicated in pregnancy. First trimester: Risk of spontaneous abortion and congenital anomalies due to hormonal disruption. Second and third trimesters: Potential . Always consult a maternal-fetal medicine specialist before taking either drug during pregnancy or lactation.