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About Breast Cancer

Breast cancer is a type of cancer that forms within the breast tissue. This can happen when healthy breast cells develop changes that cause them to rapidly grow and divide, forming a tumor. Breast cancer may spread beyond the breast to other parts of the body.

When breast cancer spreads to nearby tissue or lymph nodes, this is called locally advanced (LA) breast cancer.

If breast cancer spreads further to other organs, like the lungs, bones, liver, or brain, this is known as metastatic breast cancer (MBC).


Although people sometimes refer to "breast cancer" as a single disease, in reality, there are many types of breast cancer based on certain characteristics of the cancer cells.

After you are diagnosed, your doctor will determine which tests are needed to help guide your treatment plan.

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One way that locally advanced or metastatic breast cancer (LA/MBC) can be classified is based on the amount of HER2 protein on the surface of breast cells. If the LA/MBC cells have only small amounts of HER2 protein, the cancer is considered HER2-negative (HER2-).


HER2- LA/MBC can be classified based on whether the tumor cells contain proteins called hormone receptors.

  • Hormone receptor-positive (HR+) is a breast cancer subtype in which the cancer cells contain either the estrogen and/or progesterone receptors. These cancer cells will grow in response to estrogen and/or progesterone hormones, respectively.
  • Hormone receptor-negative (HR-) is a breast cancer subtype in which the cancer cells have little to no estrogen or progesterone receptors.

Based on whether or not your HER2- LA/MBC has hormone receptors, it can be classified as either:

HR+, HER2- Breast Cancer

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Triple-negative Breast Cancer (TNBC)

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After a patient is diagnosed with LA/MBC, a doctor may also order a blood test to determine whether the cancer is classified as “germline BRCA-mutated” (gBRCA-mutated).

BRCA1 and BRCA2 are genes that everyone has within their cells. Normally, BRCA proteins help repair damaged DNA inside the cell.

But if either the BRCA1 or BRCA2 gene has an inherited, or germline, mutation (sometimes abbreviated as a gBRCA mutation), the DNA repair processes within the cell can be defective and, in some cases, lead to the formation of tumors. Because these gBRCA-mutated cancer cells cannot use BRCA to repair their DNA, the cells rely on other DNA-repair proteins, like “poly (ADP-ribose) polymerase” (PARP), to keep the cancer alive.

If you have HER2- LA/MBC with a gBRCA mutation, there are different treatment options that may be right for you—like TALZENNA.


Hereditary BRCA mutations can be passed on from one generation to the next.

Although hereditary breast cancer is more common in women, men with inherited gBRCA mutations also have an increased risk for developing breast cancer.

Patients with hereditary breast cancer may be referred to a genetic counselor. Genetic counselors can offer guidance and education to patients and their families on BRCA testing and treatment decision-making.

Regardless of whether patients have a family history of breast cancer, gBRCA mutation testing is an important step in understanding if TALZENNA is the right type of treatment for them.

LEARN ABOUT TALZENNA HER2-=human epidermal growth factor receptor 2 (HER2)-negative.

About 1 in 10 breast cancers is hereditary

Important Safety Information and Indication

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Important Safety Information

TALZENNA may cause serious side effects, including:

Bone marrow problems called Myelodysplastic Syndrome (MDS) or Acute Myeloid Leukemia (AML). Some people who have cancer and who have received previous treatment with chemotherapy or certain other medicines for their cancer have developed MDS or AML during or after treatment with TALZENNA. MDS or AML may lead to death. If you develop MDS or AML, your healthcare provider will stop treatment with TALZENNA.

Symptoms of low blood cell counts are common during treatment with TALZENNA, but can be a sign of serious problems, including MDS or AML. Tell your healthcare provider if you have any of the following symptoms during treatment with TALZENNA:

  • weakness
  • weight loss
  • fever
  • frequent infections
  • blood in urine or stool
  • shortness of breath
  • feeling very tired
  • bruising or bleeding more easily

Your healthcare provider will do blood tests to check your blood cell counts:

  • every month during treatment with TALZENNA
  • weekly if you have low blood cell counts that last a long time. Your healthcare provider may stop treatment with TALZENNA until your blood cell counts improve.

Before taking TALZENNA, tell your healthcare provider about all of your medical conditions, including if you:

  • have kidney problems
  • are pregnant or plan to become pregnant. TALZENNA can harm your unborn baby, and may cause loss of pregnancy (miscarriage). You should not become pregnant during treatment with TALZENNA. Tell your healthcare provider right away if you are pregnant or become pregnant during treatment with TALZENNA.
    • Females who are able to become pregnant should use effective birth control (contraception) during treatment with TALZENNA and for at least 7 months after receiving the last dose of TALZENNA. Talk to your healthcare provider about forms of birth control that may be right for you.
    • Males with female partners who are pregnant or are able to become pregnant should use effective birth control during treatment with TALZENNA and for at least 4 months after receiving the last dose of TALZENNA.
  • are breastfeeding or plan to breastfeed. It is not known if TALZENNA passes into your breast milk. Do not breastfeed during treatment with TALZENNA and for at least 1 month after receiving the last dose of TALZENNA. Talk to your healthcare provider about the best way to feed your baby during this time.

Tell your healthcare provider about all the medicines you take, including prescription medicines, over-the-counter medicines, vitamins, and herbal supplements. Taking TALZENNA and certain other medicines can affect how TALZENNA works and may cause side effects.

Know the medicines you take. Keep a list of your medicines and show it to your healthcare provider and pharmacist when you get a new medicine.

How to take TALZENNA

  • Take TALZENNA exactly as your healthcare provider tells you.
  • If you miss a dose of TALZENNA or vomit, take your next dose at your regular time. Do not take an extra dose to make up for a missed dose.
  • If you take too much TALZENNA, call your healthcare provider or go to the nearest hospital emergency room right away.

The most common side effects of TALZENNA include:

  • low red blood cell counts
  • low white blood cell counts
  • low platelet counts
  • tiredness or weakness
  • increased blood glucose levels
  • increased liver function tests
  • low calcium in the blood
  • nausea
  • headache
  • vomiting
  • hair loss
  • diarrhea
  • decreased appetite

TALZENNA may cause fertility problems in males. This may affect your ability to father a child. Talk to your healthcare provider if this is a concern for you. These are not all of the possible side effects of TALZENNA.

Call your doctor for medical advice about side effects.

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.


TALZENNA is a prescription medicine used:

  • alone to treat adults with a certain type of breast cancer (human epidermal growth factor receptor 2 [HER2]-negative)
    • who have an abnormal inherited BRCA gene, and
    • whose cancer has spread to other parts of the body (locally advanced or metastatic).

Your healthcare provider will perform a test to make sure that TALZENNA is right for you. It is not known if TALZENNA is safe and effective in children.

Please see Full Prescribing Information and Patient Information.