Last reviewed 2026-04-20 · How we verify

Arimidex

At a glance

Approved indications

• Hormone receptor positive malignant neoplasm of breast

Common side effects

• Vasodilatation
• Asthenia
• Arthritis
• Pain
• Arthralgia
• Pharyngitis
• Hypertension
• Depression
• Nausea
• Rash
• Osteoporosis
• Lymphedema

Serious adverse events

• Skin reactions (lesions, ulcers, blisters)
• Allergic reactions with facial/throat swelling
• Liver function changes and hepatitis

Key clinical trials

• A Study of Elacestrant Versus Standard Endocrine Therapy in Women and Men With ER+,HER2-, Early Breast Cancer With High Risk of Recurrence (PHASE3)
• Testing Whether Hormone Therapy With Ribociclib is as Effective as Chemotherapy Followed by Hormone Therapy With Ribociclib for the Treatment of High Anatomic Stage Breast Cancer With Low Recurrence Risk, The RxFINE-Low Trial (PHASE3)
• Hormone Therapy With or Without Combination Chemotherapy in Treating Women Who Have Undergone Surgery for Node-Negative Breast Cancer (The TAILORx Trial) (PHASE3)
• A Study of LOXO-783 in Patients With Breast Cancer/Other Solid Tumors (PHASE1)
• Tamoxifen Citrate, Letrozole, Anastrozole, or Exemestane With or Without Chemotherapy in Treating Patients With Invasive RxPONDER Breast Cancer (PHASE3)
• Ribociclib And Endocrine Treatment of Physician's Choice for Locoregional Recurrent, Resected Hormone Receptor Positive HER2 Negative Breast Cancer (PHASE2)
• A Study of Tersolisib (LY4064809/STX-478) With Other Anti-Cancer Treatments in Participants With Advanced Breast Cancer With a Genetic Change (PIK3CA) (PHASE3)
• A Study of the Impact of Endocrine Therapy on Surgical Outcomes in People With Breast Cancer (PHASE2)

Primary sources

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