Epcoritamab-bysp injection may cause a serious or life-threatening reaction called cytokine release syndrome (CRS). Tell your doctor if you have an inflammatory disorder or if you have or think you may have any type of infection now. Your doctor may tell you to take certain medications before receiving epcoritamab-bysp injection to prevent this reaction. If you experience any of the following symptoms during and after your injection, tell your doctor immediately: fever, chills, fast or irregular heartbeat, difficulty breathing, shortness of breath, cough, confusion, anxiety, restlessness, headache, dizziness, lightheadedness, muscle pain, shaking, diarrhea, nausea, vomiting, tiredness, or weakness.

Epcoritamab-bysp injection may cause severe or life-threatening central nervous system reactions called immune effector cell-associated neurotoxicity syndrome (ICANS). Tell your doctor if you have or have ever had seizures, a stroke, or memory loss. If you experience any of the following symptoms, tell your doctor immediately: headache; restlessness; confusion; loss of consciousness; seizures; uncontrollable shaking or jerking of a part of the body; hearing loss; double vision; difficulty speaking or writing; difficulty walking; muscle tightening or spasms; muscle weakness; burning, throbbing, or stabbing pain; or numbness and tingling of the skin.

You may experience CRS or central nervous system reactions while you receive a dose of epcoritamab-bysp injection, but these reactions may occur afterwards. These reactions are more common with the first 3 doses of epcoritamab-bysp injection but may occur at any time during treatment. A doctor or nurse will monitor you carefully in a hospital or medical facility during your injections and for 48 hours after at least your first 3 doses of epcoritamab-bysp injection to be sure you are not having a serious reaction to the medication.

Keep all appointments with your doctor and the laboratory. Your doctor will order certain tests to check your body’s response to epcoritamab-bysp injection.

Your doctor or pharmacist will give you the manufacturer’s patient information sheet (Medication Guide) when you begin treatment with epcoritamab-bysp 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.

Talk to your doctor about the risk(s) of receiving epcoritamab-bysp injection.

Epcoritamab-bysp is used for treatment of diffuse large B-cell lymphoma (DLBCL; a type of cancer that impacts the lymphatic [infection-fighting] system in the body) that has either returned after completing treatment or failed to respond to other treatments. Epcoritamab-bysp is in a class of medications called bispecific T-cell engager antibodies. It works by killing cancer cells.

Epcoritamab-bysp comes as a solution (liquid) to be given subcutaneously (into the skin), usually in the thigh or into the lower abdomen, by a doctor or a nurse in a hospital or medical facility. It is usually given on days 1, 8, 15, and 22 on cycles 1-3, and then on days 1 and 15 for cycles 4-9 and once a month on day 1 thereafter.

Your doctor may delay or stop your treatment with epcoritamab-bysp 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 epcoritamab-bysp,

• tell your doctor and pharmacist if you are allergic to epcoritamab-bysp, any other medications, or any of the ingredients in epcoritamab-bysp injection. Ask your pharmacist or check the Medication Guide for a list of the ingredients.
• tell your doctor and pharmacist what prescription and nonprescription medications, vitamins, nutritional supplements, and herbal products you are taking or plan to take.
• tell your doctor if you have or have ever had herpes zoster (shingles) or low blood cell counts (leukopenia, neutropenia, anemia).
• tell your doctor if you are pregnant or plan to become pregnant. You must have a pregnancy test before you start treatment with epcoritamab-bysp injection. You should use birth control to prevent pregnancy during your treatment with epcoritamab-bysp injection and for 4 months after your final dose. Talk to your doctor about birth control methods that you can use. If you become pregnant while receiving epcoritamab-bysp injection, call your doctor. Epcoritamab-bysp injection may harm the fetus.
• tell your doctor if you are breastfeeding. Do not breastfeed during your treatment and for 4months after your final dose.
• if you are having surgery, including dental surgery, tell the doctor or dentist that you are receiving epcoritamab-bysp.

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

Epcoritamab-bsyb may cause side effects. Tell your doctor if any of these symptoms are severe or do not go away:

• tiredness
• muscle or bone pain
• bruising, redness or pain at the site of the injections
• fever
• stomach pain
• nausea
• diarrhea

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

• fever with cough, chest pain, tiredness, shortness of breath, painful rash, sore throat, pain on urination, or feeling weak or unwell

Epcoritamab-bysp may cause other side effects. Call your doctor if you have any unusual problems while taking 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).

Keep all appointments with your doctor and the laboratory.

Before having any laboratory test, tell your doctor and the laboratory personnel that you are receiving epcoritamab-bysp.

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.

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