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ZOLADEX is the only

GnRH agonist with FDA approval for pre- and perimenopausal women with advanced breast cancer1

GnRH=gonadotropin-releasing hormone.
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NCCN Guidelines Recommends 5 Years

For premenopausal patients receiving adjuvant endocrine therapy with ovarian suppression, NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) recommend a five-year treatment duration as an option in those with HR-positive breast cancer at higher risk of recurrence2

NCCN Category 1 evidence—based upon high-level evidence (≥1 randomized phase 3 trials or high-quality, robust meta-analyses), there is uniform NCCN consensus (≥85% support of the Panel) that the intervention is appropriate.2

Pivotal trial1,3:
The Southwest Oncology Group (SWOG) conducted a prospective, randomized clinical trial (SWOG-8692) in premenopausal women with locally advanced or metastatic hormone receptor-positive breast cancer. The study compared ZOLADEX (3.6 mg administered subcutaneously every 4 weeks) with oophorectomy.

The ZOLADEX 3.6 mg Prescribing Information contains interim data from SWOG-8692, and the publication of SWOG-8692 (Taylor et al.) represents the full dataset for the clinical trial. SWOG-8692 was originally designed as an equivalence trial with 80% power to exclude a 50% improvement in survival with oophorectomy. Due to slow accrual, the study was terminated early, resulting in a reduced final power of 60% for the alternative hypothesis of equal survival outcomes.

Best objective response comparable to oophorectomy3

22% ZOLADEX1
12% Oophorectomy1

CR=complete response; PR=partial response.

Interim data set (SWOG-8692)1:
On the basis of interim data from 124 women, the best objective response (CR+PR) for the ZOLADEX group was 22% vs 12% for the oophorectomy group. The median time to treatment failure was 6.7 months for patients treated with ZOLADEX and 5.5 months for patients treated with oophorectomy. The median survival time for the ZOLADEX arm was 33.2 months and for the oophorectomy arm was 33.6 months.

CR=complete response; PR=partial response.

Comparison of estradiol levels at baseline and after 8 weeks of ZOLADEX treatment (secondary endpoint)3

Bar graph showing the comparison of estradiol levels at baseline and after 8 weeks of ZOLADEX treatment with 117.4 pg/mL at baseline and 21.6 pg/mL after 8 weeks

Natural postmenopausal estradiol levels are ~35 pg/mL.4

Final data set (Taylor et al.)3:
The primary objective was to determine if ZOLADEX was equivalent to oophorectomy in its effect on failure-free survival and overall survival. Secondary objectives were to compare objective response rates and toxicities and to assess the endocrine effects of ZOLADEX, including estradiol levels. A subset of patients (n=33) had paired follow-up estradiol assessments at baseline and after 8 weeks of ZOLADEX treatment.

Representing patient assistance

Adverse events reported in ≥5% of patients in the pivotal trial (SWOG-8692) in the ZOLADEX group regardless of causality1

ZOLADEX(n=57) Oophorectomy(n=55)
ADVERSE EVENTS % of Patients % of Patients
Hot Flashes 70 47
Tumor Flare 23 4
Nausea 11 7
Edema 5 0
Malaise/Fatigue/Lethargy 5 2
Vomiting 4 7
Illustration of magnifying glass
A closer look at tumor flare1:

As a GnRH agonist, ZOLADEX initially causes transient increases in estrogen in the first few weeks of treatment.

  • Chronic exposure to ZOLADEX subsequently leads to suppression of gonadotropin secretion
  • Serum estradiol is suppressed to levels similar to those observed in postmenopausal women within 3 weeks following initial administration
  • A small number of patients may experience a temporary increase in bone pain, which can be managed symptomatically
Illustration of magnifying glass

From the ZOLADEX in Pre-menopausal Patients (ZIPP) study5,6

Study design: In the ZIPP study, 2710 premenopausal women with invasive, operable, node-positive or -negative early breast cancer were randomly assigned to ZOLADEX alone (3.6 mg administered subcutaneously every 4 weeks; n=469), endocrine therapy alone (20 or 40 mg daily; n=879), both therapies (n=882), or no endocrine therapy (n=476). Treatments were administered for 2 years. Women received primary treatment, including surgery with/without radiotherapy and adjuvant systemic chemotherapy, when appropriate. In this study, the endocrine therapy administered was tamoxifen.

Primary endpoint: Event-free survival
The hazard ratio (HR) for event-free survival (EFS), defined as a recurrence, new tumor, or death, was5:

  • ZOLADEX alone vs no endocrine therapy: HR 0.67 (95% CI: 0.56-0.81)
  • Endocrine therapy alone vs no endocrine therapy: HR 0.71 (95% CI: 0.60-0.84)
  • ZOLADEX and endocrine therapy vs no endocrine therapy: HR 0.65 (95% CI: 0.55-0.78)

Tolerability6
The most common side effect was hot flashes: 78 (17%) patients treated with endocrine therapy alone, 35 (26%) patients treated with ZOLADEX alone, 200 (44%) patients treated with both ZOLADEX and endocrine therapy, and 0 (0%) patients who did not receive endocrine therapy. The only other side effect reported in more than 10% of patients was weight gain: 32 (7%) patients treated with endocrine therapy alone, 5 (4%) patients treated with ZOLADEX alone, 50 (11%) patients treated with both ZOLADEX and endocrine therapy, and 0 (0%) patients who did not receive endocrine therapy.

For every 100 breast cancer patients treated with 2 years of ZOLADEX added to endocrine therapy (vs no endocrine therapy)5

Circular stat image

FEWER DEATHS AND RECURRENCES AT 15 YEARS*†

*2.8 with fewer recurrences.

†2.6 fewer deaths.

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What to expect when starting patients on ZOLADEX

Dosing and administration
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Learn more about the following indications

Prostate cancer Endometriosis
  1. ZOLADEX® (goserelin implant) 3.6 mg. Prescribing Information. TerSera Therapeutics LLC.
  2. Referenced with permission from the NCCN Clinical Practice Guidelines in Oncology (NCCN Guidelines®) for Breast Cancer. V.4.2025. © National Comprehensive Cancer Network, Inc. 2025. All rights reserved. Accessed August 15, 2025. To view the most recent and complete version of the guidelines, go online to NCCN.org. NCCN makes no warranties of any kind whatsoever regarding their content, use, or application and disclaims any responsibility for their application or use in any way.
  3. Taylor CW, Green S, Dalton WS, et al. Multicenter randomized clinical trial of goserelin versus surgical ovariectomy in premenopausal patients with receptor-positive metastatic breast cancer: an intergroup study. J Clin Oncol. 1998;16(3):994-999.
  4. De Vos FY, van Laarhoven HW, Laven JS, et al. Menopausal status and adjuvant hormonal therapy for breast cancer patients: a practical guideline. Crit Rev Oncol Hematol. 2012;84(2):252-260.
  5. Hackshaw A, Baum M, Fornander T, et al. Long-term effectiveness of adjuvant goserelin in premenopausal women with early breast cancer. J Natl Cancer Inst. 2009;101(5):341-349.
  6. Baum M, Hackshaw A, Houghton J, et al. Adjuvant goserelin in pre-menopausal patients with early breast cancer: results from the ZIPP study. Eur J Cancer. 2006;42(7):895-904.

IMPORTANT SAFETY INFORMATION

GENERAL

Systemic hypersensitivity, antibody formation, and acute anaphylactic reactions have been reported in patients receiving ZOLADEX. ZOLADEX is contraindicated in patients with known hypersensitivity to GnRH, GnRH agonist, or any of the components in ZOLADEX.

Tumor Flare Phenomenon: Transient worsening of tumor symptoms may occur in the first few weeks of therapy in patients being treated for cancer. Monitor patients at risk for complications of tumor flare including ureteral obstruction, spinal cord compression, and increased bone pain.

Hypercalcemia has been reported in patients with bone metastases treated with ZOLADEX. Monitor and manage appropriately.

ZOLADEX can cause severe cutaneous adverse reactions (SCARs), including Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP). SCARs, including SJS/TEN, DRESS, and AGEP, occurred in patients receiving ZOLADEX or other GnRH agonists, including cases with visceral involvement and/or requiring skin grafts. Monitor patients for the development of SCARs. If a SCAR is suspected, interrupt ZOLADEX until the etiology of the reaction has been determined. Consultation with a dermatologist is recommended. If a SCAR is confirmed, or for other grade 4 skin reactions, permanently discontinue ZOLADEX.

Injection site injury and vascular injury have been reported with ZOLADEX. Extra care should be taken when administering ZOLADEX to patients with low BMI and/or to patients receiving full dose anticoagulation.

FEMALES

ZOLADEX is contraindicated during pregnancy unless used for palliative treatment of advanced breast cancer. If used during pregnancy, the patient should be advised of the potential hazard to the fetus. Otherwise, pregnancy must be excluded and effective nonhormonal contraception must be used by all premenopausal women during ZOLADEX therapy and for 12 weeks following discontinuation of therapy.

ZOLADEX may cause an increase in cervical resistance. Therefore, caution is recommended when dilating the cervix for endometrial ablation.

Depression may occur or worsen in women receiving GnRH agonists, including ZOLADEX. Monitor and manage appropriately.

MALES

Hyperglycemia and an increased risk of developing diabetes have been reported in men receiving GnRH agonists. Monitor blood glucose levels and manage according to current clinical practice.

Increased risk of myocardial infarction, sudden cardiac death and stroke has been reported in association with use of GnRH agonists in men. Patients should be monitored for cardiovascular disease and be managed according to current clinical practice.

Androgen deprivation therapy may prolong the QT interval. Consider risks and benefits.

ADVERSE REACTIONS

In men, the most common adverse reactions (>10%) include hot flashes, sexual dysfunction, decreased erections and lower urinary tract symptoms.

In women, the most common adverse reactions (>20%) include hot flashes, vaginitis, headache, emotional lability, decreased libido, sweating, depression, acne, breast atrophy, seborrhea, and peripheral edema.

To report SUSPECTED ADVERSE REACTIONS, contact the FDA at 1‑800‑FDA‑1088 or www.FDA.gov/medwatch. You may also contact TerSera Therapeutics at 1‑844‑334‑4035 or medicalinformation@tersera.com.

Please see accompanying Full Prescribing Information for ZOLADEX 3.6 mg and ZOLADEX 10.8 mg.

INDICATIONS

ZOLADEX (goserelin implant) is a Gonadotropin Releasing Hormone (GnRH) agonist.

ZOLADEX 3.6 mg is indicated for:

  • Use in the palliative treatment of advanced breast cancer in pre- and perimenopausal women
  • The management of endometriosis
  • Use as an endometrial-thinning agent prior to endometrial ablation for dysfunctional uterine bleeding

ZOLADEX 3.6 mg and ZOLADEX 10.8 mg are indicated for:

  • Use in combination with flutamide for the management of locally confined carcinoma of the prostate
  • Palliative treatment of advanced carcinoma of the prostate

IMPORTANT SAFETY INFORMATION

GENERAL

Systemic hypersensitivity, antibody formation, and acute anaphylactic reactions have been reported in patients receiving ZOLADEX. ZOLADEX is contraindicated in patients with known hypersensitivity to GnRH, GnRH agonist, or any of the components in ZOLADEX.

Tumor Flare Phenomenon: Transient worsening of tumor symptoms may occur in the first few weeks of therapy in patients being treated for cancer. Monitor patients at risk for complications of tumor flare including ureteral obstruction, spinal cord compression, and increased bone pain.

Hypercalcemia has been reported in patients with bone metastases treated with ZOLADEX. Monitor and manage appropriately.

ZOLADEX can cause severe cutaneous adverse reactions (SCARs), including Stevens-Johnson syndrome/toxic epidermal necrolysis (SJS/TEN), drug reaction with eosinophilia and systemic symptoms (DRESS), and acute generalized exanthematous pustulosis (AGEP). SCARs, including SJS/TEN, DRESS, and AGEP, occurred in patients receiving ZOLADEX or other GnRH agonists, including cases with visceral involvement and/or requiring skin grafts. Monitor patients for the development of SCARs. If a SCAR is suspected, interrupt ZOLADEX until the etiology of the reaction has been determined. Consultation with a dermatologist is recommended. If a SCAR is confirmed, or for other grade 4 skin reactions, permanently discontinue ZOLADEX.

Injection site injury and vascular injury have been reported with ZOLADEX. Extra care should be taken when administering ZOLADEX to patients with low BMI and/or to patients receiving full dose anticoagulation.

FEMALES

ZOLADEX is contraindicated during pregnancy unless used for palliative treatment of advanced breast cancer. If used during pregnancy, the patient should be advised of the potential hazard to the fetus. Otherwise, pregnancy must be excluded and effective nonhormonal contraception must be used by all premenopausal women during ZOLADEX therapy and for 12 weeks following discontinuation of therapy.

ZOLADEX may cause an increase in cervical resistance. Therefore, caution is recommended when dilating the cervix for endometrial ablation.

Depression may occur or worsen in women receiving GnRH agonists, including ZOLADEX. Monitor and manage appropriately.

MALES

Hyperglycemia and an increased risk of developing diabetes have been reported in men receiving GnRH agonists. Monitor blood glucose levels and manage according to current clinical practice.

Increased risk of myocardial infarction, sudden cardiac death and stroke has been reported in association with use of GnRH agonists in men. Patients should be monitored for cardiovascular disease and be managed according to current clinical practice.

Androgen deprivation therapy may prolong the QT interval. Consider risks and benefits.

ADVERSE REACTIONS

In men, the most common adverse reactions (>10%) include hot flashes, sexual dysfunction, decreased erections and lower urinary tract symptoms.

In women, the most common adverse reactions (>20%) include hot flashes, vaginitis, headache, emotional lability, decreased libido, sweating, depression, acne, breast atrophy, seborrhea, and peripheral edema.

To report SUSPECTED ADVERSE REACTIONS, contact the FDA at 1‑800‑FDA‑1088 or www.FDA.gov/medwatch. You may also contact TerSera Therapeutics at 1‑844‑334‑4035 or medicalinformation@tersera.com.

Please see accompanying Full Prescribing Information for ZOLADEX 3.6 mg and ZOLADEX 10.8 mg.

INDICATIONS

ZOLADEX (goserelin implant) is a Gonadotropin Releasing Hormone (GnRH) agonist.

ZOLADEX 3.6 mg is indicated for:

  • Use in the palliative treatment of advanced breast cancer in pre- and perimenopausal women
  • The management of endometriosis
  • Use as an endometrial-thinning agent prior to endometrial ablation for dysfunctional uterine bleeding

ZOLADEX 3.6 mg and ZOLADEX 10.8 mg are indicated for:

  • Use in combination with flutamide for the management of locally confined carcinoma of the prostate
  • Palliative treatment of advanced carcinoma of the prostate