Trabectedin (Yondelis)

Trabectedin is the name of a chemotherapy drug. It is also known as Yondelis.

It is a treatment for: 

  • soft tissue sarcoma that has spread to other parts of the body (advanced cancer). It is for people who have already had treatment with, or are unable to have, ifosfamide and an anthracycline chemotherapy such as doxorubicin
  • ovarian cancer that has come back (relapsed). You have it with another chemotherapy drug called liposomal doxorubicin

How does trabectedin work?

Trabectedin works by sticking to the DNA Open a glossary item in cells and damaging it. This stops the cancer cells growing and multiplying.

How do you have trabectedin?

You have trabectedin into your bloodstream (intravenously).

You might have treatment through a long plastic tube that goes into a large vein in your chest. The tube stays in place throughout the course of treatment. This can be a:

  • central line
  • PICC line
  • portacath

If you don't have a central line

You might have treatment through a thin short tube (a cannula) that goes into a vein in your arm. You have a new cannula each time you have treatment.

How often do you have trabectedin?

You have trabectedin as a course of several cycles of treatment. A cycle of treatment means that you have the drug and then a rest to allow your body to recover.

Each cycle of treatment lasts 21 days (3 weeks). You usually continue to have trabectedin for as long as it is working, and the side effects aren’t too bad.

Trabectedin is given slightly differently depending on your cancer type.

Trabectedin for soft tissue sarcoma

Day 1
  • You have trabectedin through a drip over 24 hours.
Day 2
  • Your nurse disconnects your drip.
Day 3 to 21
  • You have no treatment.

You then start your next cycle of treatment.

Trabectedin for ovarian cancer

Day 1
  • You have the pegylated liposomal doxorubicin as a drip over about 90 minutes for the first cycle. As long as you don’t have a reaction, you can have this drug over about an hour for the rest of your cycles of treatment.
  • You have trabectedin as a drip over 3 hours.
Day 2 to 21
  • You have no treatment.

You then start your next cycle of treatment. 

You might have granulocyte colony stimulating factor (G-CSF) after your chemotherapy. This is to help your white blood cells recover from treatment.


You have blood tests before and during your treatment. They check your levels of blood cells and other substances in the blood. They also check how well your liver and kidneys are working.

You usually have weekly bloods for the first 6 weeks of this treatment. This gradually gets less often.

What are the side effects of trabectedin?

Side effects can vary from person to person. They also depend on what other treatments you're having. 

When to contact your team

Your doctor, nurse or pharmacist will go through the possible side effects. They will monitor you during treatment and check how you are at your appointments. Contact your advice line as soon as possible if:

  • you have severe side effects 

  • your side effects aren’t getting any better

  • your side effects are getting worse

Early treatment can help manage side effects better. 

Contact your advice line immediately if you have signs of infection, including a temperature above 37.5C or below 36C.

We haven't listed all the side effects here. Remember it is very unlikely that you will have all of these side effects. But you might have some of them at the same time.

Common side effects

These side effects happen in more than 10 in 100 people (more than 10%). You might have one or more of them. They include:

Increased risk of getting an infection

Increased risk of getting an infection is due to a drop in white blood cells. Symptoms include a change in temperature, aching muscles, headaches, feeling cold and shivery and generally unwell. You might have other symptoms depending on where the infection is.

Infections can sometimes be life threatening. You should contact your advice line urgently if you think you have an infection. 

Breathlessness and looking pale

You might be breathless and look pale due to a drop in red blood cells. This is called anaemia.

Bruising, bleeding gums or nosebleeds

This is due to a drop in the number of platelets in your blood. These blood cells help the blood to clot when we cut ourselves. You may have nosebleeds or bleeding gums after brushing your teeth. Or you may have lots of tiny red spots or bruises on your arms or legs (known as petechiae).

Tiredness and weakness (fatigue)

Tiredness and weakness (fatigue) can happen during and after treatment. Doing gentle exercises each day can keep your energy up. Don't push yourself, rest when you start to feel tired and ask others for help.

Feeling or being sick

Feeling or being sick is usually well controlled with anti sickness medicines. It might help to avoid fatty or fried foods, eat small meals and snacks and take regular sips of water. Relaxation techniques might also help.

It is important to take anti sickness medicines as prescribed even if you don’t feel sick. It is easier to prevent sickness rather than treat it once it has started.


Tell your healthcare team if you keep getting headaches. They can give you painkillers to help.


Constipation Open a glossary item is easier to sort out if you treat it early. Drink plenty of fluids and eat as much fresh fruit and vegetables as you can. Try to take gentle exercise, such as walking. Tell your healthcare team if you think you are constipated. They can prescribe a laxative.


Contact your advice line if you have diarrhoea. For example, in one day you have 2 or more loose bowel movements than usual. If you have a stoma, you might have more output than normal. Your doctor may give you anti diarrhoea medicine to take home with you after treatment.

Try to eat small meals and snacks regularly. It’s best to try to have a healthy balanced diet if you can. You don’t necessarily need to stop eating foods that contain fibre. But if your diet is normally very high in fibre, it might help to cut back on high fibre foods such as beans, nuts, seeds, dried fruit, bran and raw vegetables. 

Drink plenty to try and replace the fluid lost. Aim for 8 to 10 glasses per day.

Loss of appetite

You might lose your appetite for various reasons while having cancer treatment. Sickness, taste changes or tiredness can put you off food and drinks.

Liver changes

You might have liver changes that can cause symptoms such as yellowing of the skin and whites of the eye.

Rarely it can cause your liver to stop working properly. This can cause other symptoms such as confusion, tummy pain and generally feeling unwell.

You have regular blood tests to check for any changes in the way your liver is working.

Breathlessness and coughing

You might develop a cough or breathing problems. Let your doctor or nurse know straight away if you suddenly become breathless or develop a cough.

Sore mouth

Mouth sores and ulcers can be painful. It helps to keep your mouth and teeth clean, drink plenty of fluids and avoid acidic foods such as lemons. Chewing gum can help to keep your mouth moist. Tell your doctor or nurse if you have ulcers.

Fluid build up (oedema)

You may have swelling of your hands and legs due to a build up of fluid (oedema). 

Difficulty sleeping (insomnia)

If you have difficulty sleeping, it can help to change a few things about how you try to sleep. Try to go to bed and get up at the same time each day and spend some time relaxing before you go to bed. Some light exercise each day may also help. 

Tummy (abdominal) pain

Tell your doctor or nurse if you have this. They can check for the cause of the pain and give you medicine to help. 

Joint, back or muscle pain

You might have pain in your back or joints. Less commonly you might also develop muscle pain.

Speak to your doctor or nurse about what painkillers you can take to help with this.

High levels of creatinine in your blood

Your blood tests might show that you have high levels of a substance called creatinine.

Creatinine is a protein made by the muscles. The kidneys remove the creatinine from the body in your urine. High levels of creatinine can be a sign of different things including dehydration or that your kidneys may not be working properly. You have regular blood tests to check the levels of creatinine.

Low levels of albumin

Albumin is an important protein in your body. Low levels of albumin can cause weakness, muscle cramps and swelling in different parts of your body. You have regular blood tests to check the albumin levels. 

High levels of substances in the blood

You have a blood test before you have trabectedin. This is to check the blood creatine phosphokinase (CPK) levels. Very high levels of CPK can lead to muscle damage (a condition called rhabdomyolysis), but this is rare. It’s important to let your doctor or nurse know straight away if you have muscle pain or weakness.   

Occasional side effects

These side effects happen in between 1 and 10 out of every 100 people (between 1 and 10%). You might have one or more of them. They include:

  • an allergic reaction that can cause a rash, shortness of breath, redness or swelling of the face and dizziness - some allergic reactions can be life threatening, alert your nurse or doctor if notice any of these symptoms
  • loss of fluid from your body (dehydration)
  • low levels of potassium in the blood - you have regular blood tests to check your levels
  • numbness, weakness and tingling in hands or feet
  • hair loss
  • indigestion
  • dizziness
  • low blood pressure
  • sudden flushing of the skin
  • skin rash
  • taste changes
  • weight loss
  • inflammation around the drip site - rarely the fluid can leak out of the vein into the surrounding tissue. This can cause swelling, redness and discomfort. This could lead to damage of the tissue which may need surgery.

Rare side effects

These side effects happen in fewer than 1 in 100 people (less than 1%). You might have one or more of them. They include:

  • leaking of fluid and proteins out of the blood vessels into the tissues. This is called capillary leak syndrome. Tell your doctor if you notice any swelling
  • an irregular heartbeat
  • passing less urine
  • mottled skin
  • fluid build up on the lungs (pulmonary oedema) - symptoms could include breathlessness and cough

Coping with side effects

We have more information about side effects and tips on how to cope with them.

What else do I need to know?

Other medicines, foods and drink

Cancer drugs can interact with some other medicines and herbal products. Tell your doctor or pharmacist about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies.


It is important not to drink alcohol while having trabectedin treatment as this may cause damage to the liver. 

Pregnancy and contraception

This drug may harm a baby developing in the womb. It is important not to become pregnant or father a child while you are having treatment. Talk to your doctor or nurse about effective contraception before starting treatment.

Women must not become pregnant for at least 3 months after the end of treatment. Men should not father a child for at least 5 months after treatment. 

Loss of fertility

You may not be able to become pregnant or get someone pregnant after treatment with this drug. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.

Men might be able to store sperm before starting treatment. And women might be able to store eggs or ovarian tissue. But these services are not available in every hospital, so you would need to ask your doctor about this.    


Don’t breastfeed during this treatment and for 3 months afterwards. This drug may come through into your breast milk.

Treatment for other conditions

If you are having tests or treatment for anything else, always mention your cancer treatment. For example, if you are visiting your dentist.


Don’t have immunisations with live vaccines while you’re having treatment and for up to 12 months afterwards. The length of time depends on the treatment you are having. Ask your doctor or pharmacist how long you should avoid live vaccinations.

In the UK, live vaccines include rubella, mumps, measles, BCG, yellow fever and one of the shingles vaccines called Zostavax.

You can have:

  • other vaccines, but they might not give you as much protection as usual
  • the flu vaccine (as an injection)
  • the coronavirus (COVID-19) vaccine - talk to your doctor or pharmacist about the best time to have it in relation to your cancer treatment

Members of your household who are aged 5 years or over are also able to have the COVID-19 vaccine. This is to help lower your risk of getting COVID-19 while having cancer treatment and until your immune system Open a glossary item recovers from treatment.

Contact with others who have had immunisations - You can be in contact with other people who have had live vaccines as injections. Avoid close contact with people who have recently had live vaccines taken by mouth (oral vaccines) such as the oral typhoid vaccine. Sometimes people who have had the live shingles vaccine can get a shingles type rash. If this happens they should keep the area covered.

If your immune system is severely weakened, you should avoid contact with children who have had the flu vaccine as a nasal spray as this is a live vaccine. This is for 2 weeks following their vaccination.

Babies have the live rotavirus vaccine. The virus is in the baby’s poo for about 2 weeks and could make you ill if your immunity is low. Get someone else to change their nappies during this time if you can. If this isn't possible, wash your hands well after changing their nappy.

More information about this treatment

For further information about this treatment and possible side effects go to the electronic Medicines Compendium (eMC) website. You can find the patient information leaflet on this website.

You can report any side effect you have to the Medicines Health and Regulatory Authority (MHRA) as part of their Yellow Card Scheme.

Related links