Korserdu 345 mg film-coated tablets

• Keep this leaflet. You may need to read it again.
• If you have any further questions, ask your doctor or pharmacist.
• This medicine has been prescribed for you only. Do not pass it on to others. It may harm them, even if their signs of illness are the same as yours.
• If you get any side effects, talk to your doctor or pharmacist or nurse. This includes any possible side effects not listed in this leaflet. See section 4.

1. What KORSERDU is and what it is used for
2. What you need to know before you take KORSERDU
3. How to take KORSERDU
4. Possible side effects
5. How to store KORSERDU
6. Contents of the pack and other information

KORSERDU contains the active substance elacestrant which belongs to a group of medicines called selective estrogen receptor degraders.

This medicine is used to treat postmenopausal women and adult men who have a specific type of breast cancer that is advanced or has spread to other parts of the body (metastatic). It can be used to treat breast cancer that is estrogen receptor (ER)-positive, meaning that the cancer cells have receptors for the hormone oestrogen on their surface, and that is human epidermal growth factor receptor 2 (HER2)-negative, meaning that cancer cells have no or only a small amount of this receptor on their surface. KORSERDU is used as monotherapy (used on its own) in patients whose cancer has not responded to or progressed further following at least one line of hormonal treatment including a CDK 4/6 inhibitor and who have certain changes (mutations) in a gene called ESR1.

Your doctor will take a sample of your blood, which will be tested for these ESR1 mutations. A positive result is required for initiation of treatment with KORSERDU.

Oestrogen receptors are a group of proteins found inside the cells. They are activated when the hormone oestrogen binds to them. By binding to these receptors, oestrogen can in some cases stimulate cancer cells to grow and multiply. KORSERDU contains the active substance elacestrant that binds to the oestrogen receptors in the cancer cells and stops them from working. By blocking and destroying oestrogen receptors, KORSERDU can reduce the growth and spread of breast cancer and help to kill cancer cells.

If you have any questions about how KORSERDU works or why this medicine has been prescribed for you, ask your doctor, pharmacist, or nurse.

• you are allergic to elacestrant or any of the other ingredients of this medicine (listed in section 6).

Talk to your doctor or pharmacist before taking KORSERDU

• if you have any liver disease (examples of liver disease include cirrhosis (scarring of the liver), liver impairment or cholestatic jaundice (yellowing of the skin and eyes due to a reduced flow of bile from the liver)). Your doctor will monitor you regularly and closely for adverse reactions.

By having advanced breast cancer you may have an increased risk of developing blood clots in your veins (a type of blood vessel). It is unknown if KORSERDU also increases this risk.

KORSERDU should not be given to children and adolescents under 18 years of age.

Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines. This is because KORSERDU can affect the way some other medicines work. Also, some other medicines can affect the way KORSERDU works.

Tell your doctor if you take any of the following medicines:

• antibiotics to treat bacterial infections (such as ciprofloxacin, clarithromycin, erythromycin, rifampicin, telithromycin)
• medicine for low blood sodium (such as conivaptan)
• medicines to treat depression (such as nefazodone or fluvoxamine)
• medicine to treat anxiety and alcohol withdrawal (such as tofisopam).
• medicines for the treatment of other cancers (such as crizotinib, dabrafenib, imatinib, lorlatinib, or sotorasib)
• medicines for high blood pressure or chest pain (such as bosentan, diltiazem or verapamil)
• medicines for fungal infections (such as fluconazole, isavuconazole, itraconazole, ketoconazole, posaconazole, or voriconazole)
• medicines for HIV infection (such as efavirenz, etravirine, indinavir, lopinavir, ritonavir, nelfinavir, saquinavir, or telaprevir)
• medicines to treat irregular heartbeats (such as digoxin, dronedarone, or quinidine)
• medicines used in organ transplantation to prevent rejection (such as cyclosporine)
• medicines to prevent cardiovascular events and to treat high levels of cholesterol (such as rosuvastatin)
• medicines used to prevent seizures (such as carbamazepine, cenobamate, phenobarbital, phenytoin, or primidone)
• medicines to treat vomiting (such as aprepitant)
• herbal medicines used to treat depression containing St. John’s wort

Do not drink grapefruit juice or eat grapefruit while on treatment with KORSERDU as it may change the amount of KORSERDU in your body and increase the side effects of KORSERDU (see Section 3 “How to take KORSERDU”).

This medicine should only be used in postmenopausal women and in men.

Pregnancy

KORSERDU may harm an unborn baby. You must not take KORSERDU if you are pregnant, think you may be pregnant or are planning to have a baby. If you think you may be pregnant or planning to have a baby, ask your doctor, or pharmacist for advice before using this medicine.

If you are a woman who could become pregnant, you should use effective contraception while you are being treated with KORSERDU and for one week after stopping treatment with KORSERDU. Ask your doctor for suitable methods. If you are a woman who could become pregnant, your doctor will rule out an existing pregnancy before starting you on treatment with KORSERDU. This may include having a pregnancy test.

Breast-feeding

You must not breast-feed while on treatment with KORSERDU and for one week after the last dose of KORSERDU. During treatment, your doctor will discuss the potential risks of taking KORSERDU during pregnancy or breast-feeding.

Fertility

KORSERDU may impair fertility in women and men.

KORSERDU has no or negligible influence on the ability to drive and use machines. However, since fatigue, weakness, and difficulty sleeping have been reported in some patients taking elacestrant, caution should be observed by patients who experience those adverse reactions when driving or operating machinery.

Tell your doctor or pharmacist if you think you have accidentally taken more KORSERDU than you should. He or she will decide what to do.

If you forget to take a dose of KORSERDU, take it as soon as you remember. You may still take a forgotten dose up to 6 hours after the time you should have taken it. If more than 6 hours have passed or if you vomit after taking the dose, skip the dose for that day and take the next dose at your usual time the next day. Do not take a double dose to make up for the one that you missed.

Do not stop using this medicine without talking to your doctor or pharmacist. If treatment with KORSERDU is stopped, your condition may worsen.

If you get any side effects, talk to your doctor or nurse. This includes any possible side effects not listed in this leaflet. You can also report side effects directly via the Yellow Card Scheme Website: www.mhra.gov.uk/yellowcard or search for MHRA Yellow Card in the Google Play or Apple App Store. By reporting side effects you can help provide more information on the safety of this medicine.

• The active substance is elacestrant.
  • Each 86 mg KORSERDU film-coated tablet contains 86.3 mg of elacestrant.
  • Each 345 mg KORSERDU film-coated tablet contains 345 mg of elacestrant
• The other ingredients are:

Tablet core

Microcrystalline cellulose [E460]

Silicified microcrystalline cellulose

Crospovidone [E1202]

Magnesium stearate [E470b]

Colloidal silicon dioxide [E551]

Film-coating

Opadry II 85F105080 Blue containing polyvinyl alcohol [E1203], titanium dioxide [E171], macrogol [E1521], talc [E553b] and brilliant blue FCF aluminium lake [E133])

KORSERDU is supplied as film-coated tablets in aluminium blisters.

KORSERDU 86 mg film-coated tablets

Blue to light blue, biconvex round shaped film-coated tablet with “ME” debossed on one side and plain face on the opposite side. Approximate diameter: 8.8 mm.

KORSERDU 345 mg film-coated tablets

Blue to light blue, biconvex, oval shaped film-coated tablet with “MH” debossed on one side and plain face on the opposite side. Approximate size: 19.2 mm (length), 10.8 mm (width).

Each pack contains 28 film-coated tablets (4 blisters with 7 tablets each)

or