Clinical Experience & Use Clinical Data: Adverse Events

ARIMIDEX—with 8+ years of data1

In the initial adjuvant setting, results of the ATAC (ARIMIDEX, Tamoxifen Alone or in Combination) trial comparing anastrozole and tamoxifen in postmenopausal women with early breast cancer demonstrate that ARIMIDEX helped reduce the risk of recurrence through treatment completion and beyond, with an established safety profile for 5 years on treatment and 3+ years off treatment.1

Serious Adverse Events

In initial adjuvant therapy of postmenopausal women with hormone receptor-positive early breast cancer: results from 100-month median follow-up analysis vs tamoxifen, including 5 years of treatment and 3+ years of follow-up…1

Arimidex: established 5-year on-treatment and 3+ year off-treatment safety profile1

Serious adverse events before recurrence: annual rate*1

  1. *Rates refer to patients with an event, except for fracture episodes, where patients could have more than one episode. Patients with an "on treatment" event were not at risk for an “off treatment” event, except for fracture episodes.
  2. †As judged by the investigator.
  3. ‡A fracture episode comprised one or more fractures on the same day based on reports of adverse events and serious adverse events.

Safety profile confirmed through >46,000 woman-years of follow-up.1

  • After patients completed treatment, serious adverse events and fracture rates decreased and became similar for both treatment arms
  • Cardiovascular and cerebrovascular profile established through 8+ years
  • No excess in fracture rate seen after treatment completion
  • Continued diminished risk of endometrial cancer vs tamoxifen

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Important Information About Arimidex® (anastrozole) Tablets

Arimidex is indicated for adjuvant treatment of postmenopausal women with hormone receptor-positive early breast cancer.

Arimidex is indicated for first-line treatment of postmenopausal women with hormone receptor-positive or hormone receptor-unknown locally advanced or metastatic breast cancer and for the treatment of advanced breast cancer in postmenopausal women with disease progression following tamoxifen therapy. Patients with estrogen receptor-negative disease and patients who did not respond to previous tamoxifen therapy rarely responded to Arimidex.

Important Safety Information About Arimidex

  • Arimidex is only for postmenopausal women. Arimidex can cause fetal harm when administered to a pregnant woman. Before starting treatment with Arimidex, pregnancy must be excluded (see WARNINGS section of full Prescribing Information)
  • In women with preexisting ischemic heart disease 465/6186 (7.5%), an increased incidence of ischemic cardiovascular events occurred with Arimidex (17%) vs tamoxifen (10%). In this patient population, angina pectoris was reported in 25/216 (11.6%) vs 13/249 (5.2%) and myocardial infarction was reported in 2/216 (0.9%) vs 8/249 (3.2%) patients receiving Arimidex and tamoxifen, respectively
  • Compared to baseline, Arimidex showed a mean decrease in both lumbar spine and total hip bone mineral density. Tamoxifen showed a mean increase in these measurements. Nine percent of patients receiving Arimidex had an elevated serum cholesterol vs 3.5% of patients receiving tamoxifen
  • Common side effects seen with Arimidex vs tamoxifen in the early breast cancer trial after 5 years of treatment include hot flashes (36% vs 41%), joint disorders (including arthritis, arthrosis, arthralgia) (36% vs 29%), asthenia (19% vs 18%), mood disturbances (19% vs 18%), pain (17% vs 16%), pharyngitis (14% vs 14%), nausea and vomiting (13% vs 12%), rash (11% vs 13%), depression (13% vs 12%), hypertension (13% vs 11%), osteoporosis (11% vs 7%), peripheral edema (10% vs 11%), lymphedema (10% vs 11%), back pain (10% vs 10%), insomnia (10% vs 9%), and headache (10% vs 8%). Fractures, including fractures of the spine, hip, and wrist, occurred more often with Arimidex vs tamoxifen (10% vs 7%)
  • In the advanced breast cancer studies, the most common (occurring with an incidence of >10%) side effects occurring in women taking Arimidex included hot flashes, nausea, asthenia, pain, headache, back pain, bone pain, increased cough, dyspnea, pharyngitis, and peripheral edema. Joint pain/stiffness has been reported in association with the use of Arimidex
  • Clinical and pharmacokinetic results suggest that tamoxifen should not be administered with Arimidex. Estrogen-containing therapies should not be used with Arimidex as they may diminish its pharmacologic action

Please click here for full Prescribing Information.