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FDA Approved Sexual & Reproductive Health

Goserelin

also known as: Zoladex

AstraZeneca's Zoladex — a long-acting GnRH agonist delivered as a subcutaneous biodegradable implant. FDA-approved for advanced prostate cancer, advanced breast cancer in premenopausal women, endometriosis, and endometrial thinning prior to ablation.

A decapeptide GnRH agonist with D-Ser(tBu) at position 6 and azaGly-NH2 at position 10, formulated as a 3.6 mg monthly or 10.8 mg quarterly biodegradable subcutaneous abdominal-wall implant. Mechanism and effects parallel leuprolide and triptorelin: initial flare followed by sustained hypogonadism. Notable for FDA approval in both hormone-receptor-positive advanced breast cancer (premenopausal ovarian suppression) and advanced prostate cancer.

Mechanism of action

GnRH-receptor agonism on pituitary gonadotrophs — chronic exposure produces receptor desensitization, abolishing pulsatile LH/FSH secretion and producing reversible medical castration.

Primary uses

  • Advanced prostate cancer (palliative ADT)
  • Advanced breast cancer, premenopausal / perimenopausal women
  • Endometriosis
  • Endometrial thinning prior to endometrial ablation
  • Stage B2–C prostate cancer (with flutamide + radiotherapy)

Typical dosing

3.6 or 10.8 mg every 28 days (3.6 mg) or every 12 weeks (10.8 mg) (subcutaneous biodegradable implant (abdominal wall))

Administered via preloaded syringe-implant device into the upper abdominal wall. Flare prophylaxis with anti-androgen (bicalutamide or flutamide) is standard in symptomatic metastatic prostate cancer.

Regulatory status

FDA-approved as Zoladex (AstraZeneca, first approved 1989) — 3.6 mg implant for monthly dosing; 10.8 mg implant for every-12-week dosing. Indications: palliative treatment of advanced prostate cancer (including combination with flutamide); palliative treatment of advanced breast cancer in pre- and perimenopausal women; endometriosis; endometrial thinning prior to endometrial ablation; stage B2–C prostate cancer in combination with flutamide and radiotherapy.

References

  1. [fda-pi] Zoladex (goserelin acetate implant) Prescribing Information. TerSera Therapeutics / AstraZeneca.
  2. [pubmed] Francis PA, et al. "Adjuvant Ovarian Suppression in Premenopausal Breast Cancer." N Engl J Med, 2015;372:436-446 (SOFT trial — foundational evidence for ovarian suppression with goserelin in breast cancer).

Related peptides

Leuprolide

The prototypical long-acting GnRH agonist, FDA-approved across multiple formulations (Lupron Depot, Eligard, Fensolvi, Camcevi) for advanced prostate cancer, endometriosis, central precocious puberty, uterine fibroids, and IVF protocols.

Triptorelin

A widely used long-acting GnRH agonist — FDA-approved as Trelstar for advanced prostate cancer and as Triptodur for pediatric central precocious puberty; approved internationally (Decapeptyl, Gonapeptyl) for endometriosis, uterine fibroids, and female infertility protocols.

Histrelin

Endo Pharmaceuticals' Supprelin LA (pediatric) and Vantas (adult prostate cancer) — a 12-month subcutaneous hydrogel implant delivering histrelin for continuous GnRH-receptor suppression over a full year, minimizing dosing burden for pediatric CPP patients and adult prostate cancer patients alike.

Degarelix

Ferring's Firmagon — a GnRH antagonist for advanced prostate cancer that achieves castrate testosterone within 3 days, eliminating the clinical flare risk of GnRH-agonist therapy in patients with symptomatic bone metastases or impending spinal cord compression.

Gonadorelin

The native GnRH decapeptide — the hypothalamic signal that drives LH/FSH release and downstream testosterone/estradiol production. Historically FDA-approved (Factrel, Lutrepulse), now widely used in TRT-adjacent fertility protocols as a testicular-preservation alternative to HCG.

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Disclaimer

This entry is for educational purposes only and does not constitute medical advice. Dosing information reflects published regulatory or research data and is not a recommendation. Many compounds described here are not approved for human use in the United States. Consult a licensed medical professional before considering any peptide therapy.