Trastuzumab

The most important thing to know

ENHERTU can cause serious side effects, including: Lung problems that may be severe, life-threatening or that may lead to death. If you develop lung problems your healthcare provider may treat you with corticosteroid medicines. Tell your healthcare provider right away if you get any of the following signs and symptoms: cough trouble breathing or shortness of breath fever other new or worsening breathing symptoms (such as chest tightness, wheezing) Low white blood cell count (neutropenia).

Low white blood cell counts are common with ENHERTU and can sometimes be severe. Your healthcare provider will check your white blood cell counts before starting ENHERTU and before starting each dose. Tell your healthcare provider right away if you develop any signs or symptoms of an infection or have fever or chills during treatment with ENHERTU.

Heart problems that may affect your heart's ability to pump blood. Your healthcare provider will check your heart function before starting treatment with ENHERTU and during treatment if needed. Tell your healthcare provider right away if you get any of the following signs and symptoms: new or worsening shortness of breath coughing feeling tired swelling of your ankles or legs irregular heartbeat sudden weight gain dizziness or feeling light-headed loss of consciousness Your healthcare provider will check you for these side effects during your treatment with ENHERTU.

Your healthcare provider may reduce your dose, delay treatment or completely stop treatment with ENHERTU if you have severe side effects. Harm to your unborn baby. Tell your healthcare provider right away if you become pregnant or think you might be pregnant during treatment with ENHERTU. If you are able to become pregnant, your healthcare provider should do a pregnancy test before you start treatment with ENHERTU.

Females who are able to become pregnant should use effective birth control (contraception) during treatment with ENHERTU and for 7 months after the last dose. Males who have female partners that are able to become pregnant should use effective birth control (contraception) during treatment with ENHERTU and for 4 months after the last dose.

See "

Side effects, and when to stop

" for more information about side effects. What is ENHERTU? ENHERTU is a prescription medicine used to treat adults with: Human epidermal growth factor receptor 2 (HER2)-positive stage II or stage III early breast cancer followed by a taxane, trastuzumab and pertuzumab (THP) before surgery. Your healthcare provider will perform a test to make sure ENHERTU is right for you.

HER2-positive breast cancer that cannot be removed by surgery or has spread to other parts of the body (metastatic) in combination with pertuzumab as your first treatment. Your healthcare provider will perform a test to make sure ENHERTU in combination with pertuzumab is right for you. ENHERTU alone is a prescription medicine used to treat adults with: HER2-positive early breast cancer who have received trastuzumab (with or without pertuzumab) and taxane-based treatment before surgery and have cancer remaining in the tissue removed during surgery.

HER2-positive breast cancer that cannot be removed by surgery or that has spread to other parts of the body (metastatic), and who have received a prior anti-HER2 breast cancer treatment: for metastatic disease, or have breast cancer that has come back during or within 6 months of completing treatment for their early-stage breast cancer.

HER2-low breast cancer that cannot be removed by surgery or that has spread to other parts of the body (metastatic), and who have received a prior chemotherapy: for metastatic disease, or whose disease has returned during or within 6 months of completing adjuvant chemotherapy (after surgery). Your healthcare provider will perform a test to make sure ENHERTU is right for you.

Hormone receptor (HR)-positive, HER2-low or HR-positive, HER2-ultralow breast cancer that cannot be removed by surgery or that has spread to other parts of the body (metastatic), and who have received one or more endocrine treatments for metastatic disease. Your healthcare provider will perform a test to make sure ENHERTU is right for you.

non-small cell lung cancer (NSCLC) that has a certain mutation in the HER2 gene and cannot be removed by surgery or has spread to other parts of your body (metastatic), and who have received a prior treatment. Your healthcare provider will perform a test to make sure ENHERTU is right for you. stomach cancer called gastric or gastroesophageal junction (GEJ) adenocarcinoma that is HER2-positive and has spread to areas near your stomach (locally advanced) or that has spread to other parts of your body (metastatic), and who have received a prior trastuzumab-based regimen.

solid tumors that are HER2-positive (IHC 3+) and that cannot be removed by surgery or have spread to other parts of your body (metastatic), and who have received a prior treatment and have no other satisfactory treatment options. Your healthcare provider will perform a test to make sure ENHERTU is right for you. It is not known if ENHERTU is safe and effective in children.

Before you receive ENHERTU, tell your healthcare provider about all of your medical conditions, including if you: have lung or breathing problems have signs or symptoms of an infection have or have had any heart problems are breastfeeding or plan to breastfeed. It is not known if ENHERTU passes into your breast milk. Do not breastfeed during treatment with ENHERTU and for 7 months after the last dose.

Tell your healthcare provider about all the medicines you take, including prescription and over-the-counter medicines, vitamins, and herbal supplements. How will I receive ENHERTU? You will receive ENHERTU into your vein through an intravenous (IV) line by your healthcare provider. For the treatment of early breast cancer: Before surgery, ENHERTU is given 1 time every three weeks (21-day treatment cycle) for 4 cycles followed by THP for 4 cycles.

After HER2-targeted treatment and surgery, ENHERTU is given 1 time every three weeks (21-day treatment cycle) for 14 cycles. For the treatment of metastatic breast cancer, lung cancer, gastric cancer or o