What is daratumumab (Darzalex®)?

Daratumumab (Darzalex®) is a targeted therapy drug used to treat myeloma. It is best to read this information with our general information about targeted therapies and about myeloma.

Daratumumab belongs to a group of targeted therapy drugs known as monoclonal antibody.

Your doctor will talk to you about this treatment and its possible side effects before you agree (consent) to have treatment.

 

How daratumumab is given

You will usually be given daratumumab at a day unit. Sometimes it may be given during a stay in hospital. Daratumumab can be given on its own or in combination with other cancer drugs.

During treatment you usually see a cancer doctor, a cancer nurse or specialist nurse and a specialist pharmacist. This is who we mean when we mention doctor, nurse or pharmacist in this information.

Before or on the day of treatment, a nurse or person trained to take blood (phlebotomist) will take a blood sample from you. This is to check that your blood cells are at a safe level to have treatment. 

You will see a doctor or nurse before you have treatment. They will ask you how you have been feeling. If your blood results are okay, the pharmacist will prepare your targeted therapy. Your nurse will tell you when your treatment is likely to be ready. 

You will have medicines before the daratumumab to reduce the chance of an allergic reaction. Your nurse will give you daratumumab as an injection under the skin (subcutaneous) or into a vein as a drip (intravenous infusion).

As an injection

If you are having daratumumab as an injection, your nurse will give you the injection into your tummy area (abdomen). They will give it over 3 to 5 minutes.

As a drip (infusion) into the vein

You may have treatment through:

  • a short thin tube put into a vein in your arm or hand (cannula)
  • a fine tube that goes under the skin of your chest and into a vein close by (central line)
  • a fine tube that is put into a vein in your arm and goes up into a vein in your chest (PICC line).

Your nurse will give your first treatment slowly to reduce the chance of an allergic reaction. You may have the whole treatment in 1 day or as 2 shorter treatments over 2 days.

You may need to stay in hospital overnight. This is so the nurses can check for any signs of an allergic reaction.

After the first treatment, daratumumab can usually be given as a shorter treatment.

Your course of treatment

To begin with, you will have daratumumab once a week. Then you usually have it once every 2 weeks. Sometimes it is given every 3 weeks depending on if you are having it with other cancer drugs. Eventually you only have it once a month. Your nurse, pharmacist or doctor will discuss your treatment plan with you.

About side effects

We explain the most common side effects of this treatment here. We also include some less common side effects.

You may get some of the side effects we mention, but you are unlikely to get all of them. If you are also having treatment with other cancer drugs, you may have some side effects that we have not listed here. Always tell your doctor, nurse or pharmacist about any side effects you have.

Your doctor can give you drugs to help control some side effects. It is important to take them exactly as your nurse or pharmacist explains. This means they will be more likely to work for you. Your nurse will give you advice about managing your side effects. After your treatment is over, most side effects start to improve.

Serious and life-threatening side effects

Some cancer treatments can cause severe side effects. Rarely, these may be life-threatening. Your cancer doctor or nurse can explain the risk of these side effects to you.

Contact the hospital

Your nurse will give you telephone numbers for the hospital. If you feel unwell or need advice, you can call them at any time of the day or night. Save these numbers in your phone or keep them somewhere safe.

More information

We cannot list every side effect for this treatment. There are some rare side effects that are not listed. You can visit the electronic Medicines Compendium (eMC) for more detailed information.

Side effects while treatment is being given

Allergic reaction

Some people have an allergic reaction to this treatment. Before each treatment, you will have medicines to help prevent or reduce any reaction.

Signs of a reaction can include:

  • a blocked or tickly nose
  • a cough or tickly throat
  • shivering
  • feeling or being sick
  • feeling breathless or wheezy
  • feeling hot or flushed
  • a skin rash
  • itching
  • feeling dizzy
  • a headache
  • swelling of your face or lips
  • pain in your back, tummy or chest.

Your nurse will check for signs of a reaction during your treatment. If you feel unwell or have any of these signs, tell them straight away. If you do have a reaction, it can be treated quickly.

Sometimes a reaction can happen a few hours after treatment. If you develop any signs or feel unwell after you get home, contact the hospital straight away.

The risk of having a reaction is lower if you are having daratumumab as an injection rather than as a drip.

Problems at the injection site

If you are having daratumumab as an injection under the skin, you may have mild stinging, redness, itching or swelling in the injection area. Your nurse will monitor the area where you get your injections.

Common side effects

Risk of infection

This treatment can reduce the number of white blood cells in your blood. These cells fight infection. If the number of white blood cells is low, you are more likely to get an infection. A low white blood cell count is sometimes called neutropenia.

Your doctor may give you antibiotics and other drugs to try to stop you getting an infection. These are called prophylactic medicines.

An infection can be very serious when the number of white blood cells is low. It is important to get any infection treated as soon as possible. Contact the hospital straight away on the 24-hour contact number you have been given if:

  • your temperature goes over 37.5°C (99.5°F)
  • you suddenly feel unwell, even with a normal temperature
  • you have symptoms of an infection
  • your temperature goes below 36°C (96.8°F).

Symptoms of an infection include:

  • feeling shivery and shaking
  • a sore throat
  • a cough
  • breathlessness
  • diarrhoea
  • needing to pass urine (pee) a lot, or discomfort when you pass urine.

It is important to follow any specific advice your cancer treatment team gives you.

The number of white blood cells will usually return to normal before your next treatment. You will have a blood test before having more treatment. If your white blood cell count is low, your doctor may delay your treatment for a short time, until your cell count increases.

Bruising and bleeding

This treatment can reduce the number of platelets in your blood. Platelets are cells that help the blood to clot.

If the number of platelets is low, you may bruise or bleed easily. You may have:

  • nosebleeds
  • bleeding gums
  • heavy periods
  • blood in your urine (pee) or stools (poo)
  • tiny red or purple spots on the skin that may look like a rash.

Tell your doctor if you have any unexplained bruising or bleeding. You may need a drip to give you extra platelets. This is called a platelet transfusion.

Anaemia (low number of red blood cells)

This treatment can reduce the number of red blood cells in your blood. Red blood cells carry oxygen around the body. If the number of red blood cells is low, this is called anaemia. You may have symptoms such as:

  • pale skin
  • lack of energy
  • feeling breathless
  • feeling dizzy and light-headed.

Tell your doctor or nurse if you have these symptoms.

If you are very anaemic, you may need a drip to give you extra red blood cells. This is called a blood transfusion.

Tiredness

Feeling tired is a common side effect. Try to pace yourself and plan your day so you have time to rest. Gentle exercise, like short walks, can give you more energy. If you feel sleepy, do not drive or operate machinery.

Feeling sick

This is usually mild but your doctor can prescribe anti-sickness drugs to help. Tell your doctor if you still feel sick or it gets worse. They can give you advice or a different anti-sickness drug to try.

Diarrhoea

This treatment may cause diarrhoea. Diarrhoea means passing more stools (poo) than is usual for you, or having watery or loose stools. If you have a stoma, it will be more active than usual.

If you have diarrhoea:

  • try to drink at least 2 litres (3½ pints) of fluids each day
  • avoid alcohol, caffeine, milk products, high-fat foods and high-fibre foods
  • contact the hospital for advice.

Constipation

This treatment can cause constipation. Constipation means that you are not able to pass stools (poo) as often as you normally do. It can become difficult or painful. Here are some tips that may help:

  • Drink at least 2 litres (3½ pints) of fluids each day.
  • Eat high-fibre foods, such as fruit, vegetables and wholemeal bread.
  • Do regular gentle exercise, like going for short walks.

If you have constipation, contact the hospital for advice. Your doctor can give you drugs called laxatives to help.

Muscle spasms and back pain

This treatment can cause muscle spasms. They are usually mild. You may also get some backpain. Tell your doctor or nurse if this symptom is difficult to cope with.

Effects on the lungs

This treatment can cause changes to the lungs. Tell your doctor if you develop:

  • a cough
  • wheezing
  • breathlessness.

You should also tell them if any existing breathing problems get worse. You may have tests to check your lungs.

Numb or tingling hands or feet (peripheral neuropathy)

This treatment may affect the nerves, which can cause numb, tingling or painful hands or feet. You may find it hard to fasten buttons or do other fiddly tasks. Tell your doctor if you have these symptoms.

Headaches

This treatment may cause headaches. If this happens, tell your doctor or nurse. They can give you painkillers.

A group of drugs called non-steroidal anti-inflammatory drugs (such as ibuprofen) can cause kidney damage in people with myeloma. You should check with your doctor or nurse before taking these.

Changes in blood pressure

Your blood pressure may become higher than normal. Tell your nurse or doctor if you have headaches or feel dizzy. These can be signs of blood pressure changes.

Fluid build-up

You may gain weight or your ankles and legs may swell because of fluid building up. Tell your doctor or nurse if you notice this. If your ankles and legs swell, it can help to raise your legs using a footstool or cushion.

Less common side effects

Effects on the heart

This treatment can affect how the heart works. You may have tests to see how well your heart is working. These may be done before, during and after treatment.

If the treatment is causing heart problems, your doctor may change the type of treatment you are having.

Contact your doctor straight away on the 24-hour number the hospital has given you if you have any of these symptoms during or after treatment:
  • pain or tightness in your chest
  • breathlessness
  • dizziness
  • changes to your heartbeat.

Other conditions can cause these symptoms, but it is important to get them checked by a doctor. If you cannot get through to your doctor, call the NHS urgent advice number on 111.

Raised blood sugar levels

This treatment may raise your blood sugar levels. Symptoms of raised blood sugar include:

  • feeling thirsty
  • needing to pass urine (pee) more
  • often feeling tired.

Tell your doctor or nurse if you have these symptoms. If you have diabetes, your blood sugar levels may be higher than usual. Your doctor will talk to you about how to manage this.

Other information

Blood clot risk

Cancer and some cancer treatments can increase the risk of a blood clot. Symptoms of a blood clot include:

  • throbbing pain, redness or swelling in a leg or arm
  • suddenly feeling breathless or coughing
  • sharp chest pain, which may be worse when you cough or take a deep breath.

If you have any of these symptoms, contact the hospital straight away on the 24-hour contact number you have been given. If you cannot get through to your doctor, call the NHS urgent advice number on 111.

A blood clot is serious, but it can be treated with drugs that thin the blood (anticoagulants). Your doctor or nurse can give you more information.

You can help reduce the risk of developing a blood clot by:

  • staying active during treatment
  • drinking plenty of fluids, especially water.

You may be given anticoagulants to help prevent a clot.

Other medicines

Some medicines can affect how this treatment works or be harmful when you are having it. Always tell your cancer doctor about any drugs you are taking or planning to take, such as:

  • medicines you have been prescribed
  • medicines you buy in a shop or chemist
  • vitamins, herbal drugs and complementary therapies.

Tell other doctors, pharmacists or dentists who prescribe or give you medicines that you are having this cancer treatment.

You can visit the electronic Medicines Compendium (eMC) for more detailed information about your treatment.

Vaccinations

Vaccinations can reduce your risk of getting certain infections. Your doctor or nurse may talk to you about having vaccinations.

Doctors usually recommend that people with cancer have a flu vaccination and a coronavirus vaccination. These are both inactivated vaccinations that can help reduce the risk of infection. People with weak immune systems can have these, as they are not live vaccinations.

If your immune system is weak, you need to avoid live vaccinations. This is because they can make you unwell. Live vaccines, such as shingles, contain a very weak version of the illness they are vaccinating you against. Your cancer doctor or GP can tell you more about live and inactivated vaccinations.

Hepatitis B reactivation

If you have had Hepatitis B (a liver infection) in the past, temozolomide can make it active again. Your doctor or nurse will talk to you about this and may test you for Hepatitis B before, during, and after treatment.

Shingles

You may be more likely to develop a viral infection called shingles during this treatment. Your doctor may give you medicine to help prevent shingles.

Blood transfusions

Daratumumab can affect the result of a blood test called the indirect Coombs test. This is one of the tests that matches you to a donor’s blood before you have a blood transfusion.

Before you start daratumumab, you will have the blood tests you need for a blood transfusion. Your doctor may also give you a card to carry that explains the treatment you are having.

If you need a blood transfusion during treatment or for 6 months after, tell the person arranging it that you have had daratumumab. You can show them the card your doctor has given you.

Contraception

Your doctor will advise you not to get pregnant or make someone pregnant while having this treatment. Taking this drug while you are pregnant may harm the developing baby. It is important to use contraception to prevent pregnancy during your treatment. If you think you are pregnant at any time before or during treatment, tell your doctor straight away.

Breastfeeding

You are advised not to breastfeed while having this treatment, or for some time after treatment finishes. This is because the drugs could be passed to the baby through breast milk.

Your doctor or nurse can give you more information.

Fertility

Some cancer drugs can affect whether you can get pregnant or make someone pregnant. If you are worried about this, it is important to talk with your doctor before you start treatment.

Medical and dental treatment

If you need medical treatment for any reason other than cancer, always tell the doctors and nurses you are having cancer treatment. Give them the contact details for your cancer doctor so they can ask for advice.

If you think you need dental treatment, talk to your cancer doctor or nurse. Always tell your dentist you are having cancer treatment.