Last reviewed 2026-04-20 · How we verify

Depoestradiol (ESTRADIOL CYPIONATE)

Depoestradiol, marketed by Pfizer, is an advanced prostatic carcinoma treatment that binds to estrogen receptors, currently holding a niche market position. Its key strength lies in its unique mechanism of action and the extended patent protection until 2028. The primary risk is the presence of multiple off-patent competitors with similar mechanisms, which may limit market expansion and revenue growth.

At a glance

Approved indications

• Advanced Prostatic Carcinoma
• Contraception
• Female hypogonadism syndrome
• Menopausal flushing
• Metastatic Prostate Carcinoma
• Primary ovarian failure

Boxed warnings

• WARNINGS ESTROGENS INCREASE THE RISK OF ENDOMETRIAL CANCER Close clinical surveillance of all women taking estrogens is important. Adequate diagnostic measures including endometrial sampling, when indicated, should be undertaken to rule out malignancy in all cases of undiagnosed persistent or recurring abnormal vaginal bleeding. There is currently no evidence that the use of "natural" estrogens results in a different endometrial risk profile than "synthetic" estrogens at equivalent estrogen doses. (See WARNINGS, malignant neoplasms, Endometrial cancer .) CARDIOVASCULAR AND OTHER RISKS Estrogens with and without progestins should not be used for the prevention of cardiovascular disease. (See WARNINGS, Cardiovascular disorders .) The Women's Health Initiative (WHI) study reported increased risks of myocardial infarction, stroke, invasive breast cancer, pulmonary emboli, and deep vein thrombosis in postmenopausal women (50 to 79 years of age) during 5 years of treatment with oral conjugated estrogens (CE 0.625 mg) combined with medroxyprogesterone acetate (MPA 2.5 mg) relative to placebo. (See CLINICAL PHARMACOLOGY, Clinical Studies. ) The Women's Health Initiative Memory Study (WHIMS), a substudy of WHI, reported increased risk of developing probable dementia in postmenopausal women 65 years of age or older during 4 years of treatment with oral conjugated estrogens plus medroxyprogesterone acetate relative to placebo. It is unknown whether this finding applies to younger postmenopausal women or to women taking estrogen-alone therapy. (See CLINICAL PHARMACOLOGY, Clinical Studies .) Other doses of conjugated estrogens with medroxyprogesterone acetate, and other combinations and dosage forms of estrogens and progestins were not studied in the WHI clinical trials and, in the absence of comparable data, these risks should be assumed to be similar. Because of these risks, estrogens with or without progestins should be prescribed at the lowest effective doses and for the shortest duration consistent with treatment goals and risks for the individual woman. WHAT IS THE MOST IMPORTANT INFORMATION I SHOULD KNOW ABOUT DEPO-ESTRADIOL (AN ESTROGEN HORMONE)? Estrogens increase the chances of getting cancer of the uterus. Report any unusual vaginal bleeding right away while you are taking estrogens. Vaginal bleeding after menopause may be a warning sign of cancer of the uterine (womb). Your healthcare provider should check any unusual vaginal bleeding to find out the cause. Do not use estrogens with or without progestins to prevent heart disease, heart attacks, or strokes. Using estrogens with or without progestins may increase your chances of getting heart attacks, strokes, breast cancer, and blood clots. You and your healthcare provider should talk regularly about whether you still need treatment with DEPO-Estradiol.

Common side effects

• Deep and superficial venous thrombosis
• Pulmonary embolism
• Thrombophlebitis
• Myocardial infarction
• Stroke
• Increase in blood pressure
• Ovarian cancer
• Endometrial hyperplasia
• Endometrial cancer
• Breast cancer
• Pancreatitis
• Enlargement of hepatic hemangiomas

Key clinical trials

• Menopausal Hormones and Sympathetic Activation (PHASE4)
• Capivasertib+Fulvestrant asTreatment for Locally Advanced(Inoperable) or Metastatic HR+/HER2- Breast Cancer in Chinese Patients (PHASE3)
• Targeted Therapy Directed by Genetic Testing in Treating Patients With Locally Advanced or Advanced Solid Tumors, The ComboMATCH Screening Trial (PHASE2)
• Romosozumab as an Adjunct to Physiologic Estrogen Replacement in Functional Hypothalamic Amenorrhea (PHASE3)
• Study of ECI830 Single Agent or in Combination in Patients With Advanced HR+/HER2- Breast Cancer and Other Advanced Solid Tumors (PHASE1,PHASE2)
• A Study of LOXO-783 in Patients With Breast Cancer/Other Solid Tumors (PHASE1)
• Efficacy and Safety of Tinengotinib Tablets Combined With Fulvestrant Injection in Patients With HR Positive and HER-2 Negative Recurrent or Metastatic Breast Cancer Who Have Failed Prior Treatment (PHASE2)
• Liquid-biopsy Informed Platform Trial to Evaluate CDK4/6-inhibitor Resistant ER+/HER2- Metastatic Breast Cancer (PHASE2)

Primary sources

Every claim on this page is sourced from regulatory or scientific primary sources. See our editorial policy for full methodology.

Competitive intelligence

For the full competitive landscape — auto-detected comparators, recent regulatory actions across the set, upcoming PDUFA, patent timeline, sponsor landscape:

• Depoestradiol CI brief — competitive landscape report
• Depoestradiol updates RSS · CI watch RSS
• Pfizer portfolio CI