Alpelisib and fulvestrant

Alpelisib and fulvestrant are a cancer drug combination. You pronounce:

• alpelisib as al-pell-ih-sib

• fulvestrant as full-vest-rant

They are a treatment for post menopausal women or men with breast cancer that have either:

• locally advanced breast cancer
• secondary breast cancer . This is also called metastatic breast cancer, advanced breast cancer, or stage 4 breast cancer

You have alpelisib if your cancer has a PIK3CA gene change (mutation) . You have tests on your breast cancer cells to check for this gene change before you start treatment.

How does alpelisib and fulvestrant work?

Alpelisib is a type of targeted drug called a cancer growth blocker. It works by blocking a protein called phosphatidylinositol 3 kinase (PI3K) inside cancer cells which tell the cancer to grow. By blocking this protein apelisib may shrink the cancer or stop it growing for some time. Alpelisib is also called a PI3K inhibitor. 

Some breast cancers are called hormone sensitive or hormone receptor positive. This is because the sex hormones oestrogen and progesterone stimulate some breast cancers to grow.

Fulvestrant works by stopping oestrogen getting to the cancer cells by blocking oestrogen receptors and reducing the number of receptors the cancer cells have. This can help to slow or stop the growth of breast cancer cells.

How do you have alpelisib and fulvestrant?

You take alpelisib as tablets. You have fulvestrant as an injection into the muscle (intramuscular) in your bottom.

You swallow alpelisib tablets whole immediately after food. You should not crush, split or chew the tablets.

Taking your tablets

Speak to your pharmacist if you have problems swallowing the tablets.

Whether you have a full or an empty stomach can affect how much of a drug gets into your bloodstream.

You should take the right dose, no more or less.

Talk to your healthcare team before you stop taking a cancer drug or if you miss a dose.

How often do you have alpelisib and fulvestrant?

You have alpelisib and fulvestrant as cycles of treatment . Each cycle is 28 days (4 weeks).

You usually keep taking alpelisib and fulvestrant for as long as the treatment is working and you are not experiencing too many side effects. 

You have cycle 1 in the following way:

You might have these injections in the hospital as an outpatient, or at your GP surgery. Your doctor or practice nurse gives you the injections. Each injection takes 1 to 2 minutes.

You have cycle 2 onwards in the following way:

You then start your next cycle of treatment.

Tests

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.

What are the side effects of alpelisib and fulvestrant?

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. 

We haven't listed all the side effects here. Talk to your healthcare team if you have any new symptoms that you think might be a side effect of your treatment.

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).

Blood tests might also pick up that your blood is taking longer to clot than normal.

Changes in blood sugar levels

You might have changes to your blood sugar levels. Some of the symptoms of high blood sugar levels (hyperglycaemia) are feeling very thirsty, having a dry mouth, passing urine very often, feeling tired, blurred vision, weight loss, feeling or being sick, and fruity smelling breath.

You might get low blood sugar (hypoglycaemia). Symptoms include: sweating, feeling hungry, shaky, trembling, fast heartbeat, dizziness, changes to your mood, and feeling tired.

You may need to check your blood sugars at home and some people may start medicine to control their blood sugars. If you have diabetes  you may need to check your levels more often.  

Soreness and swelling around the fulvestrant injection site

Tell your nurse if you notice any signs of redness or irritation around the injection site. Rarely you might have some bleeding or bruising at the injection sites.

Allergic reaction

You might have an allergic reaction with this treatment. Symptoms can include a skin rash, itching, flushing, breathing problems, swelling of the face and throat, and dizziness due to low blood pressure. Some allergic reactions can be life threatening.

Tell your nurse or doctor straightaway if you notice any of these symptoms or go straight to accident and emergency (A&E).

Hot flushes and sweats 

We have some tips for coping with hot flushes in women and hot flushes in men. This information also includes some of the possible treatments. Talk to your doctor if your hot flushes are hard to cope with. They might be able to prescribe some medicines to help.

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.

Changes to the level of minerals in your blood

It’s common to have low levels of minerals in your blood, such as low potassium, calcium and magnesium.

You have regular blood tests during treatment to check this. Let your healthcare team know if you have symptoms such as cramp, muscle weakness or spasms.

Headaches

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

Taste changes

Taste changes may make you go off certain foods and drinks. You may also find that some foods taste different from usual or that you prefer to eat spicier foods. Your taste gradually returns to normal a few weeks after your treatment finishes.

Diarrhoea

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.

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.

Sore mouth, gums and lips

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 the mouth moist.

Less commonly your gums might be tender, bleed or swollen (gingivitis). You might also have cracked or chapped lips (cheilitis).

Tell your doctor or nurse if you have ulcers.

Pain in different parts of the body

You might have pain in the tummy, joints, muscles, bones, ligaments, tendons and nerves. Less commonly you might have pain along the sciatic nerve (sciatica) or your back.

Tell your treatment team if you have this. They can check the cause and give you medicine to help. 

Indigestion

This treatment can make you more likely to have indigestion (dyspepsia).Symptoms of indigestion include:

• discomfort, burning or bloating in the upper tummy (abdomen)
• feeling full early during your meal
• feeling uncomfortably full after a meal

Your doctor or nurse can prescribe antacid for indigestion or heartburn. Other medicines like anti sickness drugs may also help.

Skin changes  

Skin problems such as a skin rash, dry skin and itching are common with this treatment. 

Less commonly the skin on your hands and feet may become sore, red, or may peel. You may also have tingling, numbness, pain and dryness. This is called hand-foot syndrome or palmar plantar syndrome.

Rarely you might have a severe skin reaction. Symptoms usually start as tender red patches which leads to peeling or blistering of the skin. You might also feel feverish, and your eyes may be more sensitive to light. This is serious and could be life threatening.

Your doctor and nurse will check your skin regularly throughout your treatment.

Hair loss 

You could lose all your hair. This includes your eyelashes, eyebrows, underarms, legs and sometimes pubic hair. Your hair will usually grow back once treatment has finished but it is likely to be softer. It may grow back a different colour or be curlier than before. 

Tiredness and weakness

You might feel very tired and as though you lack energy.

Various things can help you to reduce tiredness and cope with it, for example exercise. Some research has shown that taking gentle exercise can give you more energy. It is important to balance exercise with resting.

High temperature

Tell your healthcare team straightaway if you get a high temperature. Ask them if you can take paracetamol to help lower your temperature.

Swelling of different parts of the body

Swelling of hands and feet is due to fluid build up and is very common with this treatment. This is called peripheral oedema. You might have fluid build up in other areas of the body but this is less common.

Occasionally some people develop lymphoedema. This is when lymph fluid isn’t able to drain in the normal way.

Let your doctor or nurse know if you have any swelling.

Weight loss

You might lose weight while having this treatment. Let your doctor or nurse know and they can recommend ways of maintaining your weight. Or they can refer you to a dietitian.

Inflammation of the inner lining of some of the organs and spaces in the body

This treatment can cause inflammation of the airways, digestive system and genital organs. This can cause pain, soreness and other symptoms such as shortness of breath and diarrhoea depending on what is inflamed.

Let your healthcare team know of any symptoms that are not normal for you. They can find out the cause and give you painkillers to reduce the soreness.

Kidney changes

You might have some changes in the way your kidneys work. You have regular blood tests to check how well they are working.

Liver changes

You might have liver changes that are usually mild and unlikely to cause symptoms. They usually go back to normal when treatment finishes.

Rarely you might have liver problems that change how well your liver is working.

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

High levels of an enzyme in the blood

Blood tests might pick up that you have a high enzyme called lipase in your blood. This could be a sign that this treatment is affecting how well your pancreas is working. This usually doesn’t cause symptoms and goes back to normal when you stop taking this drug. 

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:

• lack of fluid in the body (dehydration)
• difficulty staying asleep or getting to sleep (insomnia)
• eye problems such as dry eyes or blurred vision
• high blood pressure causing symptoms such as headaches, nosebleeds, blurred or double vision or shortness of breath
• changes to your breathing including difficulty breathing, breathing faster or slower than normal and a cough. This could be due to lung inflammation (pneumonitis). Contact your advice line if you get these symptoms
• toothache
• muscle spasms
• damage to your jaw bone - signs include ongoing jaw pain, swelling, numbness, heavy feeling in the jaw and loosing teeth. Contact your advice line or tell your doctor or nurse straight away 
• kidney problems causing symptoms such as weeing small amounts and less often, swelling in your legs and ankles, tiredness, confusion, feeling sick
• increased risk of blood clots that can be life threatening; signs are pain, redness and swelling where the clot is. Feeling breathless can be a sign of a blood clot in the lung. Contact your advice line or doctor straight away if you have any of these
• bleeding from the vagina . Rarely this treatment can cause vaginal discharge or a vaginal yeast infection (thrush)
• numbness or tingling in your fingers or toes

Rare side effects

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

• high levels of acids in the blood (ketoacidosis) – symptoms include difficulty breathing, headaches, feeling or being sick

• inflammation of your pancreas – symptoms include severe tummy pain, feeling or being sick, a high temperature or you may have loose poo

Coping with side effects

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

What else do you need to know?

Other medicines, foods and drinks 

Cancer drugs can interact with medicines, herbal products, and some food and drinks. We are unable to list all the possible interactions that may happen. An example is grapefruit or grapefruit juice which can increase the side effects of certain drugs.

Tell your healthcare team about any medicines you are taking. This includes vitamins, herbal supplements and over the counter remedies. Also let them know about any other medical conditions or allergies you may have.

Loss of fertility 

It is not known whether this treatment affects fertility in people. Talk to your doctor before starting treatment if you think you may want to have a baby in the future.

Pregnancy and contraception 

This treatment is only used for women who have been through the menopause . You should not take this medicine if you can still have a baby. This drug may harm a baby developing in the womb.

If you are able to have a baby you need to use 2 effective methods of contraception during treatment and for 1 week afterwards. Men should not get someone pregnant for at least 1 week after treatment. 

Talk to your doctor or nurse about effective contraception before starting treatment. Let them know straight away if you or your partner become pregnant while having treatment.

Breastfeeding

It is not known whether this drug comes through into the breast milk. Doctors usually advise that you don’t breastfeed during this treatment and for at least 1 week afterwards. 

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.

Immunisations 

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 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

For further information about each drug and the possible side effects go to the electronic Medicines Compendium (eMC) website. You can find patient information leaflets for each drug 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.