About ARIMIDEX

ARIMIDEX is an aromatase inhibitor with over 8 years of clinical data—5 years on treatment and more than 3 years of follow-up—in the initial treatment of hormone receptor-positive early breast cancer in postmenopausal women.

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ARIMIDEX is made by AstraZeneca, the same company that discovered tamoxifen and the company that has a 30-year history of helping women with breast cancer treatment.

Learn about ARIMIDEX

If you have been diagnosed with breast cancer or are new to hormonal breast cancer treatment, it's time to learn how ARIMIDEX may help reduce your risk of breast cancer recurrence.

ARIMIDEX is a prescription medicine approved for postmenopausal women with hormone receptor-positive early breast cancer. ARIMIDEX is also approved for the initial treatment of postmenopausal women with hormone receptor-positive or hormone receptor-unknown locally advanced or metastatic breast cancer and for the treatment of postmenopausal women with advanced breast cancer that has progressed following treatment with tamoxifen. ARIMIDEX is a hormonal treatment that helps fight breast cancer by lowering the amount of the hormone estrogen in the body.

Ask your doctor about ARIMIDEX, the most prescribed aromatase inhibitor.*

*IMS National Prescription Audit Plus: Therapeutic Category Report. February 2008.

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The science of ARIMIDEX

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In a complex series of reactions, the adrenal gland makes certain hormones in women, including androgens (male hormones) and estrogens (female hormones).

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When women have gone through menopause, their ovaries no longer make estrogen. Most of their estrogen is created by changing the androgens to estrogens. An enzyme called aromatase helps in this process. Androgens change to estrogens in various places in the body, such as in muscle, fat, and the liver, and also in breast tumors. Some breast cancer tumors grow when the hormone estrogen is present.

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ARIMIDEX binds to aromatase, stopping—or inhibiting—aromatase activity and the production of estrogen. For this reason, ARIMIDEX is called an aromatase inhibitor.

  • ARIMIDEX significantly lowers the concentration of certain estrogens in your body
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ARIMIDEX side effect profile

Possible Side Effects of ARIMIDEX.

Based on information from a study in patients with early breast cancer, women with a history of blockages in heart arteries (ischemic heart disease) who take ARIMIDEX may have a slight increase in this type of heart disease compared to similar patients who take tamoxifen.

ARIMIDEX can cause bone softening/weakening (osteoporosis) increasing the chance of fractures. In a clinical study in early breast cancer, there were more fractures (including fractures of the spine, hip, and wrist) with ARIMIDEX (10%) than with tamoxifen (7%).

In a clinical study in early breast cancer, some patients taking ARIMIDEX had an increase in cholesterol. Skin reactions, allergic reactions, and changes in blood tests of liver function have also been reported.

In the early breast cancer clinical trial, the most common side effects seen with ARIMIDEX include hot flashes, joint symptoms (including arthritis and arthralgia), weakness, mood changes, pain, back pain, sore throat, nausea and vomiting, rash, depression, high blood pressure, osteoporosis, fractures, swelling of arms/legs, insomnia, and headache.

In advanced breast cancer trials, the most common side effects seen with ARIMIDEX versus tamoxifen include hot flashes, nausea, decreased energy and weakness, pain, back pain, headache, bone pain, increased cough, shortness of breath, sore throat, and swelling of arms and legs. Joint pain/stiffness has been reported in association with the use of ARIMIDEX.

Patients taking ARIMIDEX were less likely than those taking tamoxifen to stop treatment because of side effects. See Important Safety Information below, and talk to your doctor to see if ARIMIDEX is right for you.

  • Prescription ARIMIDEX is only for postmenopausal women. ARIMIDEX should not be taken if you are pregnant because it may harm your unborn child
  • ARIMIDEX should not be taken with tamoxifen or estrogen-containing therapies

Please see full Prescribing Information. For more information, see your doctor.

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Important Information About ARIMIDEX

ARIMIDEX is approved for adjuvant treatment (treatment following surgery with or without radiation) of postmenopausal women with hormone receptor-positive early breast cancer.

ARIMIDEX is approved for the initial treatment of postmenopausal women with hormone receptor-positive or hormone receptor-unknown locally advanced or metastatic breast cancer and for the treatment of postmenopausal women with advanced breast cancer that has progressed following treatment with tamoxifen. Patients with hormone receptor-negative disease and patients who did not previously respond to tamoxifen therapy rarely responded to ARIMIDEX.

Important Safety Information About ARIMIDEX

  • Prescription ARIMIDEX is only for postmenopausal women. ARIMIDEX should not be taken if you are pregnant because it may harm your unborn child
  • Based on information from a study in patients with early breast cancer, women with a history of blockages in heart arteries (ischemic heart disease) who take ARIMIDEX may have a slight increase in this type of heart disease compared to similar patients who take tamoxifen
  • ARIMIDEX can cause bone softening/weakening (osteoporosis) increasing the chance of fractures. In a clinical study in early breast cancer, there were more fractures (including fractures of the spine, hip, and wrist) with ARIMIDEX (10%) than with tamoxifen (7%)
  • In a clinical study in early breast cancer, some patients taking ARIMIDEX had an increase in cholesterol. Skin reactions, allergic reactions, and changes in blood tests of liver function have also been reported
  • In the early breast cancer clinical trial, the most common side effects seen with ARIMIDEX include hot flashes, joint symptoms (including arthritis and arthralgia), weakness, mood changes, pain, back pain, sore throat, nausea and vomiting, rash, depression, high blood pressure, osteoporosis, fractures, swelling of arms/legs, insomnia, and headache
  • In advanced breast cancer trials, the most common side effects seen with ARIMIDEX versus tamoxifen include hot flashes, nausea, decreased energy and weakness, pain, back pain, headache, bone pain, increased cough, shortness of breath, sore throat, and swelling of arms and legs. Joint pain/stiffness has been reported in association with the use of ARIMIDEX
  • ARIMIDEX should not be taken with tamoxifen or estrogen-containing therapies

Please click here for full Prescribing Information.

You are encouraged to report negative side effects of prescription drugs to the FDA. Visit www.FDA.gov/medwatch or call 1-800-FDA-1088 (1-800-332-1088).