Cetrorelix vs Degarelix
Written by Aaron CuhaReviewed Sep 2026
The short answer
Two GnRH blocking drugs used in totally different settings. One prevents eggs from releasing too early during fertility treatment. The other pushes testosterone down in prostate cancer. Same way of working, different dose, different length of use, and no reason to swap one for the other.
- Cetrorelix people
- 564
- Cetrorelix nulls
- 0
- Degarelix people
- 610
- Degarelix nulls
- 0
Dose
Approved medicine. No human dose established for unlabelled uses
Labeled amounts sit on the prescribing information. This page records what trials measured, not a personal dose.
FDA-approved (Cetrotide)
Dose
Approved medicine. No human dose established for unlabelled uses
Labeled amounts sit on the prescribing information. This page records what trials measured, not a personal dose.
FDA-approved on 24 December 2008 under NDA 022201, sold as Firmagon, to treat advanced prostate cancer. No boxed warning. Not approved for any use beyond that, including prostate cancer that has not spread, any use in women, or any use in healthy adults.
First-hand reports are counted on each profile and never added together. This page sets two published records side by side. It does not pick a winner.
Column A
CetrorelixCetrorelix (GnRH antagonist)
An FDA-approved drug used in fertility treatment to stop ovulation from happening too early.
Column B
DegarelixDegarelix (Firmagon), GnRH receptor antagonist
A hormone blocker approved in 2008 for advanced prostate cancer. In its main study of 610 men, testosterone was down to castration level by day 3 in about 96 percent on degarelix, and in none on the older drug, leuprolide. Over 12 months it held testosterone down just as well. 40 percent had reactions where the shot went in, against under 1 percent on leuprolide. The study built to test whether it is easier on the heart was stopped early and found no difference.
Side by side, on the facts we can check
| What we compare | Cetrorelix | Degarelix |
|---|---|---|
| Category | Hormone | Hormone |
| FDA status | FDA-approved (Cetrotide) | FDA-approved on 24 December 2008 under NDA 022201, sold as Firmagon, to treat advanced prostate cancer. No boxed warning. Not approved for any use beyond that, including prostate cancer that has not spread, any use in women, or any use in healthy adults. |
| Half-life | ~5-63 hours (formulation dependent) | About 53 days terminal, driven by slow release from the subcutaneous depot. |
| Molecular weight | 1,431.1 Da | About 1632 Da as the free base, per the label. A decapeptide with five D-amino acids. |
| How it works | It blocks GnRH receptors. That stops LH and FSH release right away. | It blocks the GnRH receptor in the pituitary gland directly. That stops the hormones that drive the testes right away, so testosterone falls within days with no first surge. This is the opposite of how leuprolide, goserelin and triptorelin work. Those drugs get their effect by first overworking the same receptor. Degarelix also forms a little store under the skin where it was injected, and seeps out slowly. That explains both why it lasts so long in the body and why so many people react at the shot site. |
| Studies in people | 2 | 3 |
| Evidence | Moderate: 1 completed trial, 564 people given it | Moderate: 2 completed trials, 610 people given it |
| Legal status, US | FDA-approved, prescription only | FDA-approved, prescription only |
Frequently asked questions
What is the difference between Cetrorelix and Degarelix?
Cetrorelix: An FDA-approved drug used in fertility treatment to stop ovulation from happening too early. Degarelix: A hormone blocker approved in 2008 for advanced prostate cancer. In its main study of 610 men, testosterone was down to castration level by day 3 in about 96 percent on degarelix, and in none on the older drug, leuprolide. Over 12 months it held testosterone down just as well. 40 percent had reactions where the shot went in, against under 1 percent on leuprolide. The study built to test whether it is easier on the heart was stopped early and found no difference.
Which has stronger research evidence, Cetrorelix or Degarelix?
Each compound gets a band worked out from facts we counted, with the math shown. Cetrorelix is Moderate (1 completed trial, 564 people given it). Degarelix is Moderate (2 completed trials, 610 people given it). That counts how much has been done in people. It does not rate whether either one works, and neither one is called the winner.
Are Cetrorelix and Degarelix FDA-approved?
Cetrorelix: FDA-approved (Cetrotide). Degarelix: FDA-approved on 24 December 2008 under NDA 022201, sold as Firmagon, to treat advanced prostate cancer. No boxed warning. Not approved for any use beyond that, including prostate cancer that has not spread, any use in women, or any use in healthy adults..
Reviewed Sep 2026. This page puts two published records side by side. It is for learning, and it is not medical advice. When this site shows a dose, it is the dose a trial or a clinic actually used, or what people say they did, with the source attached. None of it tells you what to take.