Sacituzumab govitecan (Trodelvy®)

Most triple negative breast cancer cells have too much of a protein called TROP2 on their surface. TROP2 proteins send signals to cancer cells to tell them to grow.

Sacituzumab govitecan attaches to TROP2 proteins. The sacituzumab blocks signals from TROP2 to the cancer cells. This stops cancer cells from growing and dividing.

Then it delivers the chemotherapy drug SN-38 directly to the breast cancer cells and destroys them. By targeting the cancer cells, the chemotherapy drug causes less harm to healthy cells in your body.

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

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

You may get some of the side effects we mention, but you are unlikely to get all of them. And you may have some side effects, including rarer ones, that we have not listed here. 

Always tell your doctor, nurse or pharmacist about any side effects you have. They can give you: 

• drugs to help control some side effects
• advice about managing side effects. 

It is important to take any drugs exactly as explained. This means they will be more likely to work for you. 

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

Your doctor, nurse or pharmacist will give you 24-hour contact numbers for the hospital. If you feel unwell or need advice, you can call at any time of the day or night. Save these numbers in your phone or keep them somewhere safe.

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

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. If you have any of the following symptoms, contact the hospital straight away on the 24-hour number:

• a temperature above 37.5°C 
• a temperature below 36°C 
• you feel unwell, even with a normal temperature
• you have symptoms of an infection.

Symptoms of an infection include:

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

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

Your white blood cell count 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.

You may be given a drug called G-CSF. This encourages the body to make more white blood cells. You have it as a small injection under the skin.

This treatment can increase the risk of a chest infection (pneumonia). If you have any of the following symptoms, contact your doctor straight away:

• a cough
• breathlessness
• coughing up mucus (phlegm)
• a fever, with a temperature over 37.5°C (99.5°F).

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 feel:

• very low in energy
• breathless 
• dizzy and light-headed. 

If you have these symptoms, contact the hospital straight away on the 24-hour number. You may need treatment for anaemia. If you are very anaemic, you may need a drip to give you extra red blood cells. This is called a blood transfusion.

Your doctor, nurse or pharmacist will prescribe anti-sickness drugs to help prevent or control sickness. Take the drugs exactly as they tell you to, even if you do not feel sick. It is easier to prevent sickness than to treat it after it has started.

If you feel sick, take small sips of fluid often and eat small amounts regularly. It is important to drink enough fluids. If you continue to feel sick, or if you are sick (vomit) 1 to 2 times in 24 hours, contact the hospital on the 24-hour number as soon as possible. They will give you advice. They may change your anti-sickness treatment. Let them know if you still feel sick.

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

Your doctor, nurse or pharmacist may give you anti-diarrhoea drugs to take at home. 

If you have diarrhoea or a mild increase in stoma activity, follow their advice about: 

• taking anti-diarrhoea drugs 
• how much and what type of fluids to drink 
• any changes to your diet that might help. 

Contact the hospital straight away on the 24-hour number if:

• you have diarrhoea at night 
• you have uncomfortable stomach cramps
• you have diarrhoea 4 or more times in a day 
• you have a moderate increase in stoma activity 
• the anti-diarrhoea drugs do not work within 24 hours.

You may need to give a stool sample, or go to hospital to have fluids through a drip or antibiotics.

This treatment can cause pain in the tummy (abdomen). Tell your doctor or nurse if this happens so they can help.

If you have any bleeding from the back passage (rectum), contact the hospital straight away.

This treatment can affect your appetite. Don’t worry if you do not eat much for 1 or 2 days. But if your appetite does not come back after a few days, or if you are losing weight, tell your doctor, nurse or pharmacist. They can give you advice. They may give you food or drink supplements. Or they may suggest changes to your diet or eating habits to help.

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 on the 24-hour number for advice. They can give you drugs called laxatives to help. 

If you have not been able to pass stools for over 2 days and are being sick, contact the 24-hour number straight away. 

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 and may help make side effects easier to deal with.

You should be cautious when driving, using tools or operating machines after your treatment. If you feel sleepy, do not drive or operate machinery.

This treatment can disrupt your sleep. If you are having trouble sleeping, tell your doctor or nurse. They can give you advice, and may prescribe medicines to help.

Your hair will get thinner. Or you may lose all the hair from your head. You may also lose your eyelashes and eyebrows, as well as other body hair. Hair loss usually starts after your first or second treatment.

Your nurse can talk to you about ways to cope with hair loss. There are ways to cover up hair loss if you want to. Your scalp may be sensitive. It is important to cover your head to protect your skin when you are out in the sun.

This treatment may affect your skin. It may cause a rash, which might be itchy. Your doctor or nurse can tell you what to expect. If your skin feels dry, try using an unperfumed moisturising cream every day.

Always tell your doctor or nurse about any changes to your skin. They can give you advice and may prescribe creams or medicines to help.

This treatment can raise your blood sugar levels and increase the risk of diabetes. 

Signs of raised blood sugar include:

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

Tell your doctor or nurse if you have these symptoms. They can do tests to check your blood sugar level and give you advice.

If you already have diabetes, your blood sugars may be higher than usual. You may need to check them more often, or make changes to your diabetic treatment. Your diabetic doctor or nurse will talk to you about how to manage this.

This treatment may cause headaches. If you have headaches, tell your doctor, nurse or pharmacist. They can give you advice about painkillers that may help. Tell them if the headache does not get better, or gets worse.

You may get pain in your muscles or joints. If this happens, tell your doctor or nurse. They can give you advice and painkillers or other drugs to help. Being physically active and keeping to a healthy weight may help with the pain. It can keep your joints flexible and reduce stress on them. If the pain does not get better, tell your doctor or nurse. They may talk to you about changing to a different hormonal drug.

Cancer and some cancer treatments can increase the risk of a blood clot. Contact the hospital straight away on the 24-hour number if you have any of these symptoms during or after treatment:

• throbbing pain or swelling in a leg or arm
• reddening of the skin in the area – if you have black or brown skin, this can be harder to notice, but the skin might become darker
• suddenly feeling breathless or coughing.

Always call 999 if you have:

• chest pain
• difficulty breathing.

A blood clot is serious, but it can be treated with drugs called anticoagulants. These thin the blood. Your doctor, nurse or pharmacist can give you more information about preventing and treating blood clots.

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

• medicines you have been prescribed
• medicines you buy in a shop, pharmacy or online
• vitamins or supplements 
• herbal drugs and complementary or homeopathic therapies
• recreational drugs – for example, cannabis.

Doctors usually recommend that people with cancer have vaccinations for flu and for coronavirus (covid). These help reduce your risk of serious illness from these infections. Most people can have these vaccines, including people with weak immune systems.

If your immune system is weak, you should not have live vaccinations. Live vaccines can make you unwell because they contain a very weak version of the illness they will protect you against. Live vaccines include Zostavax^®, which is a shingles vaccine, and the yellow fever vaccine.

It is important to ask your doctor, nurse or pharmacist for advice about having vaccinations. They can explain what vaccines are right for you and when it is best to have them.

Your doctor, nurse or pharmacist will advise you not to get pregnant or make someone pregnant while having this treatment and for some time afterwards. The drugs may harm a developing baby. It is important to use contraception to prevent pregnancy. Follow their advice about:

• what types of contraception to use 
• how long after treatment you should continue to use contraception. 

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

Your doctor, nurse or pharmacist can give you more information.

If you need medical treatment for any reason other than cancer, always tell the healthcare professional that you are having cancer treatment. Give them the contact details for your cancer doctor or cancer team so they can ask for advice.

If you have appointments with a dentist, always tell them you are having cancer treatment. Talk to your cancer team before you have any dental treatment.