Belantamab Mafodotin Injection

What is this medication?

BELANTAMAB MAFODOTIN (bel AN ta mab MA foe DOE tin) treats multiple myeloma, a type of bone marrow cancer. It works by blocking a protein that causes cancer cells to grow and multiply. This helps to slow or stop the spread of cancer cells.

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

COMMON BRAND NAME(S): BLENREP

What should I tell my care team before I take this medication?

They need to know if you have any of these conditions:

  • Bleeding problems
  • Eye or vision problems
  • An unusual or allergic reaction to belantamab mafodotin, other medications, foods, dyes, or preservatives
  • If your or your partner are pregnant or trying to get pregnant
  • Breastfeeding

How should I use this medication?

This medication is infused into a vein. It is given by your care team in a hospital or clinic setting.

A special MedGuide will be given to you before each treatment. Be sure to read this information carefully each time.

This medication is not approved for use in children.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.

NOTE: This medicine is only for you. Do not share this medicine with others.

What if I miss a dose?

Keep appointments for follow-up doses. It is important not to miss your dose. Call your care team if you are unable to keep an appointment.

What may interact with this medication?

Interactions have not been studied.

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

What should I watch for while using this medication?

Your condition will be monitored carefully while you are receiving this medication.

Your vision may be tested before and during use of this medication. Tell your care team right away if you have any change in your eyesight.

This medication can cause eye or vision problems. It is important that you use preservative-free artificial tears at least 4 times a day during treatment. Do not wear contact lenses during treatment unless your care team tells you that you can.

Be careful brushing or flossing your teeth or using a toothpick because you may get an infection or bleed more easily. If you have any dental work done, tell your dentist you are receiving this medication.

Talk to your care team if you or your partner may be pregnant. Serious fetal side effects can occur if you take this medication during pregnancy and for 4 months after the last dose. You will need a negative pregnancy test before starting this medication. Contraception is recommended while taking this medication and for 4 months after the last dose. Your care team can help you find the option that works for you.

If your partner can get pregnant, use a condom during sex while taking this medication and for 6 months after the last dose.

Do not breastfeed while taking this medication and for 3 months after the last dose.

This medication may cause infertility. Talk to your care team if you are concerned about your fertility.

What side effects may I notice from receiving this medication?

Side effects that you should report to your care team as soon as possible:

  • Allergic reactions—skin rash, itching, hives, swelling of the face, lips, tongue, or throat
  • Dryness or irritation of the eyes, eye pain, change in vision, sensitivity to light
  • Infection—fever, chills, cough, sore throat, wounds that don't heal, pain or trouble when passing urine, general feeling of discomfort or being unwell
  • Infusion reactions—chest pain, shortness of breath or trouble breathing, feeling faint or lightheaded
  • Liver injury—right upper belly pain, loss of appetite, nausea, light-colored stool, dark yellow or brown urine, yellowing skin or eyes, unusual weakness or fatigue
  • Low red blood cell level—unusual weakness or fatigue, dizziness, headache, trouble breathing
  • New or worsening eye pain, redness, irritation, or discharge
  • Unusual bruising or bleeding

Side effects that usually do not require medical attention (report these to your care team if they continue or are bothersome):

  • Cough
  • Diarrhea
  • Eye irritation or itching
  • Fatigue
  • Runny or stuffy nose
  • Sore throat

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

Where should I keep my medication?

This medication is given in a hospital or clinic. It will not be stored at home.

NOTE: This sheet is a summary. It may not cover all possible information. If you have questions about this medicine, talk to your doctor, pharmacist, or health care provider.

© 2026 Elsevier/Gold Standard (2025-11-07 00:00:00)

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