Eribulin mesylate (Halaven)

Eribulin is a chemotherapy drug used to treat advanced breast cancer. It is licensed in the UK for people who have already had at least two other courses of chemotherapy. You must have already had an anthracycline drug, for example doxorubicin or epirubicin, and a taxane, for example docetaxel or paclitaxel, unless there is a reason you cannot have these drugs. Researchers are also looking at eribulin in trials for other cancer types.

Eribulin is also called Halaven and its full name is eribulin mesylate. It was originally developed from a sea sponge called Halichondria okadai but is now made in the laboratory.

Eribulin works by stopping (inhibiting) the cancer cells from separating into two new cells. So it blocks the growth of the cancer. It is a type of drug called a microtubule inhibitor.

You have eribulin into your bloodstream (intravenously). You can have it through a thin, short tube (a cannula) put into a vein in your arm each time you have treatment. Or you may have it through a central line, a portacath or a PICC line. These are long, plastic tubes that give the drugs directly into a large vein in your chest. You have the tube put in just before your course of treatment starts and it stays in place as long as you need it.

You usually have chemotherapy as a course of several cycles of treatment. Each cycle of eribulin treatment lasts 3 weeks. You have eribulin on the first day. You then have a break for a week and have eribulin again on the 8th day. You then have no treatment for two weeks. Your next cycle of treatment starts 3 weeks after the first dose of eribulin.

The side effects associated with eribulin are listed below. You can use the links to find out more about each side effect. For general information, see our cancer drug side effects section.

More than 10 in every 100 people have one or more of the side effects listed below.

Temporary drop in the number of blood cells made by the bone marrow, causing

• Increased risk of getting an infection from a drop in white blood cells – it is harder to fight infections and you can become very ill. You may have headaches, aching muscles, a cough, sore throat, pain passing urine or feel cold and shivery
• Tiredness and breathlessness due to a drop in red blood cells (anaemia) – you may need a blood transfusion
• Bruising more easily due to a drop in platelets – you may have nosebleeds, bleeding gums after brushing your teeth, or lots of tiny red spots or bruises on your arms or legs (known as petechia)

Some of these side effects can be life threatening, particularly infections. You should contact your doctor if you have any of these effects. Your doctor will check your blood counts regularly to see how well your bone marrow is working.

Other common side effects include

• Tiredness (fatigue) during and after treatment in half of the people (50%) having eribulin
• Hair thinning in about half of people (50%) but hair grows back once the treatment ends
• Loss of appetite
• Numbness or tingling in fingers and toes in just over 3 out of 10 people (30%), which can cause difficulty with fiddly things such as doing up buttons – this starts within a few days or weeks of starting treatment. Your doctor may suggest you have a reduced dose of eribulin or stop treatment for a while
• Feeling or being sick in about 3 out of every 10 people (30%), but this is usually well controlled with anti sickness medicines
• Constipation in 1 out of 4 people (25%) – your doctor or nurse may give you laxatives to help prevent this but do tell them if you are constipated for more than 3 days
• Loss of weight
• Aching muscles and joints
• Diarrhoea in about 1 out of 5 people (20%) – drink plenty of fluid and tell your doctor or nurse if diarrhoea becomes severe, or continues for more than 3 days
• Headaches
• Shortness of breath and a cough
• This drug may have a harmful effect on a developing baby – do talk to your doctor or nurse about contraception before having treatment if there is any chance that you or your partner could become pregnant
• Women may stop having periods (amenorrhoea) but this may be temporary

Between 1 and 10 in every 100 people have one or more of these.

• A sore mouth in less than 1 out of 10 people (9%)
• Some people develop soreness, redness and peeling of the palms of the hands and soles of the feet, (Palmar–Plantar syndrome) which may cause tingling, numbness, pain and dryness
• Dizziness
• Eye problems including blurred vision, sore, itchy, dry eyes, or infection – eye drops can help
• Low levels of potassium in your blood (hypokalaemia) – you will have blood tests to check the levels of potassium and other compounds, such as calcium and phosphate
• Taste changes
• Liver changes that are very mild and unlikely to cause symptoms – the liver will almost certainly go back to normal when treatment finishes, but you will have regular blood tests to check how well your liver is working
• Temperature, chills and flu like symptoms

You won’t get all these side effects. A side effect may get worse through your course of treatment. Or you may have more side effects as the course goes on. This depends on

• How many times you've had a drug before
• Your general health
• How much of the drug you have (the dose)
• Other drugs you are having

Talk to your doctor, pharmacist or nurse about all your side effects so they can help you manage them. Your nurse will give you a contact number. You can ring them if you have any questions or problems. They can give you advice or reassure you. If in doubt, call them.

Tell your doctor about any other medicines you are taking, including vitamins, herbal supplements and other over the counter remedies – some drugs can react together.

You should not have immunisations with live vaccines while you are having chemotherapy or for at least 6 months afterwards. In the UK, these include rubella, mumps, measles (usually given together as MMR), BCG and yellow fever. You can have other vaccines, but they may not give you as much protection as usual until your immune system has fully recovered from your chemotherapy.

It is safe for you to be in contact with other people who've had live vaccines as injections. There can be problems with oral vaccines, but not many people in the UK have oral vaccines now. So there is usually no problem in being with any baby or child who has recently had any vaccination in the UK. You might need to make sure that you aren't in contact with anyone who has had oral polio, cholera or typhoid vaccination recently, particularly if you live abroad.