Blenrep

Blenrep is used to treat adults with relapsed or refractory multiple myeloma (MM) who have received at least 2 prior lines of therapy, including a proteasome inhibitor and an immunomodulatory agent. It is used in combination with bortezomib and dexamethasone. Blenrep is given by intravenous infusion every 3 weeks.

Blenrep (belantamab mafodotin) was initially approved by the FDA in August 2020 under the accelerated approval designation. On March 20, 2023, the FDA withdrew approval after the DREAMM-3 clinical trial failed to meet its primary endpoint. On October 23, 2025, Blenrep was reapproved for r/r MM in combination with bortezomib and dexamethasone, supported by data from the DREAMM-7 phase III clinical trial, which reported:

• A 51% reduction in the risk of death with Blenrep plus bortezomib/dexamethasone versus daratumumab therapy
• Tripled progression-free survival from 10.4 to 31.3 months.

Blenrep (belantamab mafodotin) is an antibody-drug conjugate (ADC) that combines a targeting antibody with a cancer-killing drug called MMAF. The antibody specifically binds to BCMA, a protein found on multiple myeloma cells and important for myeloma cell growth and survival.

Once Blenrep attaches to the cancer cell, it is pulled inside, where MMAF is released. MMAF disrupts the cell's ability to divide, leading to cancer cell death.

Blenrep belongs to the drug class called BCMA-directed antibody and microtubule inhibitor conjugates. The BCMA pathway is important for myeloma cell growth and survival.

Your healthcare provider will give you Blenrep as an infusion into your vein over about 30 minutes.

• It is usually given every 3 weeks.
• Your healthcare provider will decide how many treatments you will need.

What happens if I miss a dose?

If you miss any appointments, call your healthcare provider as soon as possible to reschedule your appointment.

Blenrep carries a Boxed Warning for eye problems.

Eye Problems (Boxed Warning)

Eye problems are common with Blenrep and can also be severe. Blenrep can cause changes to the surface of your eye, which can lead to symptoms of eye problems, including:

• Decreased vision
• Blurred vision
• Dry eyes
• Sensitivity to light
• Feeling like something is in your eyes
• Eye irritation
• Eye pain

Ulcers on the surface of the eye (corneal ulcers), including those with infection, may also happen during treatment with Blenrep.

Tell your healthcare provider right away if you notice any new or worsening eye symptoms or vision changes during treatment with Blenrep. Your healthcare provider will refer you to an eye care specialist (such as an ophthalmologist or optometrist) to check your eyes before you start treatment, before you receive each dose of Blenrep, and as needed for any new or worsening eye problems. It is important that you:

• Keep all of your eye care appointments because some changes can happen without symptoms and may only be seen on an eye exam.
• Use preservative-free artificial tears at least 4 times per day, starting with your first infusion and continuing until the end of Blenrep treatment.
• Avoid wearing contact lenses during treatment with Blenrep unless directed by your eye care specialist.
• Use caution when driving or operating machinery because Blenrep may cause changes to your vision.

Because of the risk of eye problems, Blenrep is available only through a restricted program called the Blenrep Risk Evaluation and Mitigation Strategy (REMS). Your healthcare provider will give you the Blenrep REMS Patient Guide, which describes the risk of eye problems, and will explain the REMS program to you. To receive Blenrep, you must enroll in the REMS program and receive eye exams during treatment.

Blenrep REMS is a safety program required by the Food and Drug Administration (FDA) to manage the risk of eye problems while receiving this medicine.

• Under this program, prescribers must be certified in the Blenrep REMS by enrolling and completing training, must counsel patients receiving Blenrep on the risk of ocular toxicity and the need formonitoring via ophthalmic (eye) exams before each dose.
• You will also be provided with the Blenrep REMS Patient Guide, and you must adhere to monitoring.
• Healthcare settings that dispense Blenrep must be certified in Blenrep REMS by enrolling and must obtain authorization before dispensing.

Further information is available at www.BLENREPREMS.com and 1-855-690-9572.

Absolute Contraindications

There are no specific absolute contraindications to Blenrep.

Caution Needed

Before receiving Blenrep, tell your healthcare provider about all your medical conditions, including if you have:

• Have or had vision or eye problems
• Have or had bleeding problems
• Are pregnant or plan to become pregnant. Blenrep can harm your unborn baby.
• Are breastfeeding or plan to breastfeed.

It is not known if Blenrep is safe and effective in children.

Pregnancy

Females who can become pregnant:

• Your healthcare provider will do a pregnancy test before you start treatment with Blenrep.
• Use effective birth control during treatment and for 4 months after the last dose. Talk to yourhealthcare provider about birth control methods you can use during this time.
• Tell your healthcare provider if you become pregnant or think you may be pregnant during treatment with Blenrep.

Males with female partners who can become pregnant:

• Use effective birth control during treatment with Blenrep and for 6 months after the last dose.

Breastfeeding

It is not known if Blenrep passes into your breast milk. Do not breastfeed during treatment and for 3 months after the last dose.

Common Side Effects

The most common side effects of Blenrep when given with bortezomib and dexamethasone are:

• Eye problems (see above)
• Upper respiratory tract infection
• Liver problems
• Diarrhea
• Tiredness
• Pneumonia
• Cataracts
• COVID-19 infection.

The most common severe abnormal blood test results during treatment with Blenrep include decreases inplatelets, white blood cells, and hemoglobin, and increases in certain liver enzymes.

Tell your healthcare provider right away if you get new or worsening unexplained signs or symptoms of lung problems, including shortness of breath, chest pain, or cough.

Your healthcare provider may decrease your dose, temporarily stop, or completely stop treatment with Blenrep if you get serious side effects.

Blenrep may affect fertility in males and females, which may affect your ability to have children. Talk to yourhealthcare provider if this is a concern for you.

Serious Side Effects

Blenrep can cause the following serious side effects, in addition to eye problems described above.

Decrease in Platelets (thrombocytopenia)

Platelets help your blood clot. Low platelets are common with Blenrep and can be severe. Your healthcare provider will monitor blood counts before and during treatment. Tell your healthcare provider immediately if you experience:

• Unusual bleeding
• Easy bruising
• Bleeding gums
• Nosebleeds
• Blood in your urine or stool.

Harm to an Unborn Baby

Blenrep may harm an unborn baby. Use effective contraception during Blenrep treatment if you are a woman who can get pregnant.

These are not all of the possible side effects of Blenrep. Call your doctor for medical advice about side effects. You may report side effects to the FDA at 1-800-FDA-1088.

Adult Dose of Blenrep for R/R MM

• Initially: 2.5 mg/kg intravenously over 30 minutes.
• Administer once every 3 weeks for 8 cycles in combination with bortezomib and dexamethasone.
• After 8 cycles: 2.5 mg/kg every 3 weeks as a single agent.

Tell your healthcare provider about all medicines you take, including prescription medications, over-the-counter medicines, vitamins and supplements, and herbal products.

No formal drug interaction studies have been performed with Blenrep.

Active Ingredient: belantamab mafodotin-blmf

Inactive Ingredients: citric acid monohydrate, edetate disodium (disodium edetate dihydrate), polysorbate 80, sodium citrate (trisodium citrate dihydrate), trehalose (trehalose dihydrate).

Blenrep is manufactured by GlaxoSmithKline LLC Philadelphia PA, 19104.