This medication is used to treat a certain type of cancer (multiple myeloma). Daratumumab belongs to a class of drugs known as monoclonal antibodies. It works by slowing or stopping the growth of cancer cells.

Read the Patient Information Leaflet if available from your pharmacist before you start using daratumumab and each time you receive this medication. If you have any questions, ask your doctor or pharmacist.

This medication is given by injection into a vein by a health care professional. It is given as directed by your doctor on a treatment schedule, usually once a week for the first 6 to 9 weeks (depending on your medical condition). Afterward, your doctor may direct you to receive this medication less often. Follow your doctor's treatment schedule carefully.

Infusion reactions may happen during or soon after the infusion of this drug. Your doctor may prescribe other medications before and after each treatment to help prevent these side effects. Get medical help right away if you have any symptoms of infusion reactions such as itchy/runny nose, nausea, vomiting, throat irritation, fast heartbeat, trouble breathing, fever, cough, headache, chills, dizziness, or chest discomfort.

The dosage is based on your medical condition, weight, and response to treatment.

To get the most benefit, do not miss any doses. To help you remember, mark your calendar with a reminder.

See also How to Use section.

Tiredness, back pain, joint pain, diarrhea, or loss of appetite may occur. If any of these effects last or get worse, tell your doctor or pharmacist promptly.

People using this medication may have serious side effects. However, you have been prescribed this drug because your doctor has judged that the benefit to you is greater than the risk of side effects. Careful monitoring by your doctor may decrease your risk.

Tell your doctor right away if you have any serious side effects, including:

• easy bruising/bleeding
• numb/tingling skin
• swelling hands/ankles/feet
• blurred vision
• eye pain

This medication may lower your ability to fight infections. This may make you more likely to get a serious (rarely fatal) infection or make any infection you have worse. Tell your doctor right away if you have any signs of infection (such as sore throat that doesn't go away, fever, chills, cough).

A very serious allergic reaction to this drug is rare. However, get medical help right away if you notice any symptoms of a serious allergic reaction, including:

• rash
• itching/swelling (especially of the face/tongue/throat)
• severe dizziness
• trouble breathing

This is not a complete list of possible side effects. If you notice other effects not listed above, contact your doctor or pharmacist.

In the US - Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088 or at www.fda.gov/medwatch.

In Canada - Call your doctor for medical advice about side effects. You may report side effects to Health Canada at 1-866-234-2345.

Before using daratumumab, tell your doctor or pharmacist if you are allergic to it; or if you have any other allergies. This product may contain inactive ingredients, which can cause allergic reactions or other problems. Talk to your pharmacist for more details.

Before using this medication, tell your doctor or pharmacist your medical history, especially of:

• chronic obstructive pulmonary disease (COPD)
• liver disease (such as hepatitis B)

Daratumumab can make you more likely to get infections or may make current infections worse. Stay away from anyone who has an infection that may easily spread (such as chickenpox, COVID-19, measles, flu). Talk to your doctor if you have been exposed to an infection or for more details.

Tell your health care professional that you are using daratumumab before having any immunizations/vaccinations. Avoid contact with people who have recently received live vaccines (such as flu vaccine inhaled through the nose).

To lower the chance of getting cut, bruised, or injured, use caution with sharp objects like razors and nail cutters, and avoid activities such as contact sports.

Before having surgery, tell your doctor or dentist about all the products you use (including prescription drugs, nonprescription drugs, and herbal products).

Older adults may be at greater risk for serious infections while using this drug.

Tell your doctor if you are pregnant or plan to become pregnant. You should not become pregnant while using daratumumab. Daratumumab may harm an unborn baby. Ask about reliable forms of birth control while using this medication and for 3 months after the last dose. If you become pregnant, talk to your doctor right away about the risks and benefits of this medication.

It is unknown if this drug passes into breast milk. Consult your doctor before breastfeeding.

Drug interactions may change how your medications work or increase your risk for serious side effects. This document does not contain all possible drug interactions. Keep a list of all the products you use (including prescription/nonprescription drugs and herbal products) and share it with your doctor and pharmacist. Do not start, stop, or change the dosage of any medicines without your doctor's approval.

This medication may interfere with certain lab tests (such as Coombs' test), possibly causing false test results. Make sure lab personnel and all your doctors know you use this drug.

If someone has overdosed and has serious symptoms such as passing out or trouble breathing, call 911. Otherwise, call a poison control center right away. US residents can call 1-800-222-1222. Canada residents can call 1-844-764-7669.

Do not share this medication with others.

Lab and/or medical tests (such as complete blood count, test for hepatitis B virus) should be done before you start using this medication and while you are using it. Keep all medical and lab appointments. Consult your doctor for more details.

It is important to get each dose of this medication as scheduled. If you miss a dose, ask your doctor or pharmacist right away for a new dosing schedule. Do not double the dose to catch up.

Not applicable. This medication is given in a clinic and will not be stored at home.

Your condition can cause complications in a medical emergency. For information about enrolling in MedicAlert, call 1-888-633-4298 (US) or 1-800-668-1507 (Canada).