FDA Approves Zoladex (goserelin) for Locally Confined and Advanced Prostate Cancer

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FDA Published May 12, 2026 Medically reviewed May 12, 2026 DOI ↗ By Dr. Julia Lee, PhD · Oncology, Genomics & Drug Development

Key Takeaway

Consider Zoladex 10.8 mg every 12 weeks for androgen deprivation in prostate cancer, with similar efficacy to the 3.6 mg monthly dose.

The FDA has approved Zoladex (goserelin), a gonadotropin-releasing hormone (GnRH) agonist, for two indications in prostate cancer. For locally confined stage T2b-T4 (stage B2-C) carcinoma of the prostate, Zoladex is indicated in combination with flutamide, starting 8 weeks prior to radiation therapy and continuing during radiation. For advanced prostate cancer, Zoladex is indicated as palliative treatment. The approval is based on studies showing similar long-term endocrine responses, objective responses, and survival compared to orchiectomy for the 3.6 mg dose, and pharmacodynamic equivalence for the 10.8 mg dose. The 10.8 mg implant is administered subcutaneously every 12 weeks, offering a convenient dosing schedule for clinicians.

＋ Clinical Details (Mechanism · Dosing · Trial Data · Warnings)

Mechanism of Action

ZOLADEX is a Gonadotropin Releasing Hormone (GnRH) agonist. It suppresses serum testosterone levels.

Indication & Patient Population

ZOLADEX is indicated for: Use in combination with flutamide for the management of locally confined Stage T2b-T4 (Stage B2-C) carcinoma of the prostate; Use as palliative treatment of advanced carcinoma of the prostate.

Dosing & Administration

ZOLADEX 10.8 mg should be administered subcutaneously every 12 weeks into the anterior abdominal wall below the navel line. For Stage B2-C prostatic carcinoma, treatment with ZOLADEX and flutamide should start 8 weeks prior to initiating radiation therapy and continue during radiation therapy. A treatment regimen using one ZOLADEX 3.6 mg depot, followed in 28 days by one ZOLADEX 10.8 mg depot, should be administered. For advanced prostate cancer, ZOLADEX is intended for long-term administration unless clinically inappropriate. No dosage adjustment is necessary for patients with renal or hepatic impairment. ZOLADEX 10.8 mg implant is not indicated in women.

Key Clinical Trial Data

In controlled studies of patients with advanced prostatic cancer comparing ZOLADEX 3.6 mg to orchiectomy, the long-term endocrine responses and objective responses were similar between the two treatment arms. Duration of survival was similar between the two treatment arms in a major comparative trial. In controlled studies, ZOLADEX 10.8 mg implant produced pharmacodynamically similar effect in terms of suppression of serum testosterone to that achieved with ZOLADEX 3.6 mg implant. Clinical outcome similar to that produced with the use of the ZOLADEX 3.6 mg implant administered every 28 days is predicted with the ZOLADEX 10.8 mg implant administered every 12 weeks.

Warnings & Contraindications

Not reported in label.

Place in Therapy

ZOLADEX is a GnRH agonist used for androgen deprivation therapy in prostate cancer. It is indicated for both locally confined disease (in combination with flutamide and radiation) and advanced disease as palliative treatment. The 10.8 mg implant provides a 12-week dosing interval.

Study Details

Study typeFda approval

PublishedJan 1996

View Original Abstract ↓

1 INDICATIONS AND USAGE ZOLADEX is a Gonadotropin Releasing Hormone (GnRH) agonist indicated for: Use in combination with flutamide for the management of locally confined carcinoma of the prostate ( 1.1 ) Use as palliative treatment of advanced carcinoma of the prostate ( 1.2 ) 1.1 Stage B2-C Prostatic Carcinoma ZOLADEX is indicated for use in combination with flutamide for the management of locally confined Stage T2b-T4 (Stage B2-C) carcinoma of the prostate. Treatment with ZOLADEX and flutamide should start 8 weeks prior to initiating radiation therapy and continue during radiation therapy [see Dosage and Administration ( 2.1 ) and Clinical Studies ( 14.1 )]. 1.2 Prostatic Carcinoma ZOLADEX is indicated in the palliative treatment of advanced carcinoma of the prostate [see Dosage and Administration ( 2.2 ) and Clinical Studies ( 14.2 )]. In controlled studies of patients with advanced prostatic cancer comparing ZOLADEX 3.6 mg to orchiectomy, the long-term endocrine responses and objective responses were similar between the two treatment arms. Additionally, duration of survival was similar between the two treatment arms in a major comparative trial. In controlled studies of patients with advanced prostatic cancer, ZOLADEX 10.8 mg implant produced pharmacodynamically similar effect in terms of suppression of serum testosterone to that achieved with ZOLADEX 3.6 mg implant. Clinical outcome similar to that produced with the use of the ZOLADEX 3.6 mg implant administered every 28 days is predicted with the ZOLADEX 10.8 mg implant administered every 12 weeks. The automatic safety feature of the syringe aids in the prevention of needlestick injury.