Moxetumomab pasudotox-tdfk injection may cause a serious or life-threatening reaction called capillary leak syndrome (a condition that causes excess fluid in the body, low blood pressure, and low levels of a protein [albumin] in the blood). If you experience any of the following symptoms, call your doctor immediately: swelling of the face, hands, feet, ankles, or lower legs; weight gain; shortness of breath; cough; fainting; dizziness or lightheadedness; or fast or irregular heartbeat.

Moxetumomab pasudotox-tdfk injection may cause hemolytic uremic syndrome (a potentially life-threatening condition that involves injury to red blood cells, causing anemia and kidney problems). Tell your doctor if you have or have ever had kidney disease. If you experience any of the following symptoms, tell your doctor immediately: red or bloody stools or diarrhea; decreased urination; blood in urine; changes in mood or behavior; seizures; confusion; shortness of breath; swelling of the face, arms, hands, feet, ankles, or lower legs; unusual bleeding or bruising; stomach pain; vomiting; fever; pale skin; or unusual tiredness or weakness.

Keep all appointments with your doctor and the laboratory. Your doctor may order certain tests before, during, and after your treatment to check your body’s response to moxetumomab pasudotox-tdfk injection.

Your doctor or pharmacist will give you the manufacturer’s patient information sheet (Medication Guide) when you begin treatment with moxetumomab pasudotox-tdfk injection and each time you refill your prescription. Read the information carefully and ask your doctor or pharmacist if you have any questions. You can also visit the Food and Drug Administration (FDA) website (http://www.fda.gov/Drugs/DrugSafety/ucm085729.htm) or the manufacturer’s website to obtain the Medication Guide.

Moxetumomab pasudotox-tdfk injection is used to treat hairy cell leukemia (cancer of a certain type of white blood cell) that has returned or has not responded after at least two other cancer treatments. Moxetumomab pasudotox-tdfk injection is in a class of medications called monoclonal antibodies. It works by helping your immune system to slow or stop the growth of cancer cells.

Moxetumomab pasudotox-tdfk injection comes as a powder to be mixed with liquid and injected into a vein by a doctor or nurse in a medical office or hospital. It is usually injected slowly over a period of 30 minutes on days 1, 3, and 5 of a 28-day treatment cycle. This cycle may be repeated for up to 6 cycles. The length of treatment depends on how well your body responds to the medication and any side effects you experience.

During your treatment, your doctor will ask you to drink up to twelve 8-oz glasses of liquids such as water, milk or juice every 24 hours on days 1 through 8 of each 28-day treatment cycle.

Moxetumomab may cause serious reactions during or after you receive your infusion. You will be given medications 30 to 90 minutes before your infusion and after your infusion to help prevent reactions to moxetumomab. Your doctor may need to stop your treatment if you experience certain side effects. Tell your doctor if you experience any of the following symptoms: dizziness, fainting, wheezing or difficulty breathing, shortness of breath, fast heartbeat, muscle pain, nausea, vomiting, headache, fever, chills, cough, fainting, hot flashes, or flushing. It is important for you to tell your doctor how you are feeling during your treatment with moxetumomab pasudotox-tdfk injection. Call your doctor right away or get immediate emergency medical attention if you experience any of these symptoms after you leave your doctor’s office or medical facility.

Your doctor may reduce your dose, delay or stop your treatment with moxetumomab pasudotox-tdfk injection, or treat you with additional medications depending on your response to the medication and any side effects that you experience. Talk to your doctor about how you are feeling during your treatment.

This medication may be prescribed for other uses; ask your doctor or pharmacist for more information.

Before receiving moxetumomab pasudotox-tdfk injection,

• Tell your doctor and pharmacist if you are allergic to moxetumomab, any other medications, or any of the ingredients in moxetumomab pasudotox-tdfk injection. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
• Tell your doctor and pharmacist what other prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take. Your doctor may need to change the doses of your medications or monitor you carefully for side effects.
• Tell your doctor if you have or have ever had medical problems.
• Tell your doctor if you are pregnant or plan to become pregnant. You will need to have a pregnancy test before you start moxetumomab. You should not become pregnant while you are receiving moxetumomab pasudotox-tdfk injection and for at least 30 days after your final dose. Talk to your doctor about birth control methods that will work for you. If you become pregnant while receiving moxetumomab pasudotox-tdfk injection, call your doctor immediately. Moxetumomab pasudotox-tdfk injection may harm the fetus.
• Tell your doctor if you are breastfeeding or plan to breastfeed.

Unless your doctor tells you otherwise, continue your normal diet.

If you miss an appointment to receive an infusion, call your doctor as soon as possible to reschedule your appointment.

Moxetumomab pasudotox-tdfk injection may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• Constipation
• Pale skin
• Tiredness
• Dry eye or eye pain
• Eye swelling or infection
• Vision changes

Some side effects can be serious. If you experience any of these symptoms or those listed in the IMPORTANT WARNING or HOW sections, call your doctor immediately or get emergency medical treatment:

• Muscle cramps; numbness or tingling; irregular or fast heartbeat; nausea; or seizures

Moxetumomab pasudotox-tdfk injection may cause other side effects. Call your doctor if you have any unusual problems while receiving this medication.

If you experience a serious side effect, you or your doctor may send a report to the Food and Drug Administration’s (FDA) MedWatch Adverse Event Reporting program online (http://www.fda.gov/Safety/MedWatch) or by phone (1-800-332-1088).

Ask your pharmacist any questions you have about moxetumomab pasudotox-tdfk injection.

It is important for you to keep a written list of all of the prescription and nonprescription (over-the-counter) medicines you are taking, as well as any products such as vitamins, minerals, or other dietary supplements. You should bring this list with you each time you visit a doctor or if you are admitted to a hospital. It is also important information to carry with you in case of emergencies.