Degarelix Reference

Plain English

What it is

Degarelix is an FDA-approved prescription medicine sold under the brand name Firmagon. It is a man-made hormone blocker (called a GnRH receptor antagonist) used to treat advanced prostate cancer.

What people use it for

Doctors use it to lower testosterone, the hormone that helps prostate cancer grow. It is given as a shot by a healthcare professional in a clinic, so it is not something people use on their own. Unlike some older hormone drugs in its class, it does not cause an early surge in testosterone before levels drop.

What the science shows

In a large year-long study that compared it head to head with leuprolide (another hormone drug), degarelix lowered testosterone within a few days while leuprolide did not, and it kept levels low for the rest of the year. The researchers found it lowered testosterone faster than leuprolide and avoided the early hormone flare.

The catch

This is a cancer drug that must be prescribed and given by a clinician, and off-label or self-administered use is not safe and is outside FDA approval. Common effects include injection-site reactions, hot flashes, and rises in liver enzymes. Lowering testosterone over time can weaken bones, and the label notes the therapy may prolong the heart's QT interval in people who already have heart or electrolyte risks.

Reference summary

Degarelix is a label-verified GnRH antagonist depot with a Phase 3 head-to-head (CS21) against leuprolide showing comparable testosterone suppression by day 28, faster onset (suppression within days), and absence of the testosterone microsurge / clinical flare that GnRH agonists produce in the first 1 to 2 weeks. pepSmart surfaces label-reference content only.

Regulatory and posture

Categories

Reproductive, Hormonal

Aliases

Firmagon, GnRH antagonist, GnRH antagonist depot, Degarelix acetate, FE200486

Evidence posture

human - Oncology drug. Prescription-only and clinician-administered; off-label or self-administered use is not safe and is outside FDA approval. Prolonged androgen-deprivation therapy carries bone-density loss, cardiovascular events, hot flashes, libido loss, ALT/AST elevations, and label-noted QT/QTc considerations in at-risk patients.

Regulatory status

FDA-approved prescription medication (Firmagon). Indicated for advanced prostate cancer. Prescription-only and clinician-administered. EU- and Japan-approved with the same indication.

Content review status

label verified

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