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Degarelix (Firmagon)

Degarelix Acetate (N-acetyl-D-Nal(2)-D-Cpa-D-Pal(3)-Ser-Aph(Hor)-D-Aph(Cbm)-Leu-ILys-Pro-D-Ala-NH2)

FDA Approved

Approved status applies to specific products, routes, and indications, not every use context discussed online.

An FDA-approved monthly injection (Firmagon) for advanced prostate cancer that rapidly lowers testosterone levels within days, helping slow cancer growth. Unlike some older treatments, it avoids an initial temporary spike in testosterone that can briefly worsen symptoms.

20 studiesUpdated 2026-03-10Subcutaneous
Clinical bottom lineApproved

Degarelix (Firmagon) is FDA-approved.

Use according to current labeled indication and prescribing guidance.

Safety Summary

In the CS21 Phase III trial (n=207 degarelix, n=201 leuprolide), the overall adverse event rate was 79% for degarelix vs 78% for leuprolide PMID 19035858. Injection site reactions occurred in 35% of degarelix patients vs <1% leuprolide (pain 28%, erythema 17%, swelling 6%, induration 4%, nodule 3%), mostly transient and mild-to-moderate. Hot flashes: 26% degarelix vs 21% leuprolide. Liver enzyme elevations: 10% vs 5%, mostly Grade 1-2 and reversible. In the extension study (median 43 months, n=385), injection site infections including abscess occurred in 1% of patients (FDA Label). Anti-degarelix antibody development was observed in 10% of patients at 1 year but did not affect efficacy or safety (FDA Label). The 2025 meta-analysis PMID 41216753 confirmed higher overall AE rate with degarelix (RR 1.07, p<0.001) but no increase in severe complications (RR 0.89, p=0.43) or death (RR 0.64, p=0.16). A 2026 FAERS analysis identified 53 previously unlabeled AE signals including interstitial lung disease, cardiac failure, osteoporotic fracture, and hyperkalemia PMID 41776145.

Clinical check-in

If real-world use or exposure is being considered, review potential interactions, contraindications, and monitoring needs with a licensed clinician rather than relying on summary copy alone.

See cited studies on this page (20)

Cited sources

Every claim on this page links to one of the 20 sources below. Identifiers are PubMed (PMID), ClinicalTrials.gov (NCT), or DOI; click through to the source of record before acting on a claim.

  1. 1PMID 19035858PubMed
  2. 2PMID 24661333PubMed
  3. 3PMID 21788033PubMed
  4. 4PMID 34459214PubMed
  5. 5PMID 34350976PubMed
  6. 6PMID 41216753PubMed
  7. 7PMID 27390687PubMed
  8. 8PMID 29624800PubMed
  9. 9PMID 27756786PubMed
  10. 10PMID 23258223PubMed
  11. 11PMID 24954791PubMed
  12. 12PMID 29398594PubMed
  13. 13PMID 29545772PubMed
  14. 14PMID 41776145PubMed
  15. 15PMID 20110043PubMed
  16. 16PMID 41781018PubMed
  17. 17PMID 37060432PubMed
  18. 18PMID 29606109PubMed
  19. 19PMID 28753747PubMed
  20. 20PMID 34396210PubMed