Patient leaflet - Retsevmo 40 mg film-coated tablets
1. What Retsevmo is and what it is used for
Retsevmo is an anticancer medicine containing the active substance selpercatinib.
It is used to treat the following cancers which are caused by certain abnormal changes in the RET gene and which have spread and/or cannot be removed by surgery: - A type of lung cancer called non-small cell lung cancer, in adults who have not previously been
treated with a RET inhibitor medicine.
Thyroid cancer (any type) in adults and adolescents 12 years and older if radioactive iodine
treatment, when appropriate, has failed to control your cancer.
A rare type of thyroid cancer called medullary thyroid cancer in adults and adolescents
12 years and older.
Your doctor will perform a test to check if your cancer has a change in the RET gene to make sure that Retsevmo is right for you.
How Retsevmo works
In patients whose cancer has an altered RET gene, the change in the gene causes the body to make an abnormal RET protein, which can lead to uncontrolled cell growth and cancer. Retsevmo blocks the action of the abnormal RET protein and so may slow or stop the growth of the cancer. It may also help to shrink the cancer.
If you have any questions about how Retsevmo works or why this medicine has been prescribed for you, ask your doctor.
2. What you need to know before you take Retsevmo
Do not take Retsevmo
if you are allergic to selpercatinib or any of the other ingredients of this medicine
(listed in section 6).
if you have ever developed a severe skin rash or skin peeling, blistering and/or mouth sores
after taking Retsevmo.
Warnings and precautions
Talk to your doctor before taking Retsevmo:
- If you have lung or breathing problems other than lung cancer.
- If you have high blood pressure.
If you have been told that you have an abnormality of your heart tracing after an
electrocardiogram (ECG) known as prolonged QT interval.
- If you have problems with your thyroid or levels of thyroid hormone.
Retsevmo may affect fertility in females and males, which may affect your ability to have
children. Talk to your doctor if this is a concern for you.
- If you have a recent history of significant bleeding.
Retsevmo may cause hypersensitivity reactions such as fever, rash and pain. If you experience any of these reactions, talk to your doctor. After checking your symptoms, your doctor may ask you to take corticosteroids until your symptoms are better.
A fast breakdown of cancer cells (tumour lysis syndrome, TLS) can occur when you are taking Retsevmo. This can cause irregular heartbeat, kidney failure or abnormal blood test results. Talk to your doctor if you have a history of kidney problems or low blood pressure, because this may increase the risks associated with TLS.
Retsevmo may cause irregular hip joint growth or damage in paediatric patients (<18 years of age). If you experience pain in the hip or knee or have an unexplained limp, talk to your doctor.
This medicine can cause serious skin reactions. Stop using Retsevmo and seek medical attention immediately if you notice any of the symptoms related to these serious skin reactions described in section 4.
See section 4, “Possible side effects”, and talk to your doctor if you have any symptoms.
What your doctor will check before and during your treatment
Retsevmo may cause severe, life-threatening, or fatal inflammation of the lungs. Your doctor
will monitor you before and during treatment with Retsevmo for symptoms. Tell your doctor right away if you notice any symptoms of lung problems including breathlessness, cough and raised temperature.
Retsevmo may affect your blood pressure. You will have your blood pressure measured before
and during treatment with Retsevmo.
Retsevmo may affect the way your liver works. Tell your doctor right away if you develop
symptoms of liver problems including: jaundice (yellow discoloration of the skin and eyes), loss of appetite, nausea or vomiting, or pain on the upper right side of your stomach area. - Retsevmo may result in abnormal ECGs. You will have an ECG taken before and during your
treatment with Retsevmo. Tell your doctor if you experience fainting as it may be a symptom of abnormal ECG.
Retsevmo may affect how your thyroid works. Your doctor will monitor your thyroid function
before and during treatment with Retsevmo.
You will have regular blood tests before and during treatment with Retsevmo, to check your liver
function and electrolytes (such as sodium, potassium, magnesium and calcium) in your blood. - If you are under 18 years of age, your doctor may monitor your growth during treatment.
If you have hip, knee, or other leg pain let your doctor know.
Children and adolescents
Retsevmo is not intended for use in patients less than 18 years of age in lung cancer. The thyroid cancer (including medullary thyroid cancer) indications do not cover children younger than 12 years of age.
Other medicines and Retsevmo
Tell your doctor or pharmacist if you are taking, have recently taken or might take any other medicines.
In particular, tell your doctor or pharmacist before taking Retsevmo if you are taking the following: - medicines that may increase the concentration of Retsevmo in the blood:
○ Clarithromycin (used to treat bacterial infections)
○ Itraconazole, ketoconazole, posaconazole, voriconazole (used to treat fungal infections) ○ Atazanavir, ritonavir, cobicistat (used to treat HIV infections/AIDS)
medicines that may reduce the effectiveness of Retsevmo:
○ Carbamazepine (used to treat epilepsy, nerve pain, bipolar disorder) ○ Rifampicin (used to treat tuberculosis (TB) and some other infections) ○ St. John’s wort (a herbal product used to treat mild depression and anxiety) ○ Omeprazole, lansoprazole, or other proton pump inhibitors used to treat heartburn, ulcers, and acid reflux. If you are taking any of these medicines, then take Retsevmo with a full meal ○ Ranitidine, famotidine or other H2 blockers used to treat ulcers and acid reflux. If you are taking any of these medicines, then you need to take them 2 hours after taking Retsevmo - medicines whose concentration in the blood might be increased by Retsevmo:
○ Repaglinide (used to treat type 2 diabetes and control blood sugar)
○ Dasabuvir (used to treat hepatitis C)
○ Selexipag (used to treat pulmonary arterial hypertension)
○ Digoxin (used to treat heart disorders)
○ Lovastatin and simvastatin (used to treat high cholesterol)
○ Dabigatran (used to prevent and treat blood clots)
medicines that may be less effective when taken with Retsevmo:
○ Levothyroxine (used to treat hypothyroidism)
Pregnancy, breast-feeding and fertility
Pregnancy
If you are pregnant, think you may be pregnant or are planning to have a baby, ask your doctor before taking this medicine.
You should not use Retsevmo during pregnancy, since the effect of Retsevmo on the unborn is not known.
Breast-feeding
Do not breast-feed during treatment with Retsevmo as Retsevmo could harm a breast-fed baby. It is not known if Retsevmo passes into breast milk. You should not breast-feed for at least one week after your last dose of Retsevmo.
Contraception
It is recommended that women avoid becoming pregnant and that men do not father children during treatment with Retsevmo, because this medicine could harm the baby. If there is any possibility that the person taking this medicine may become pregnant or father a child, they must use adequate contraception during treatment and for at least one week after the last dose of Retsevmo.
Fertility
Retsevmo can affect your ability to have children. Talk to your doctor to seek advice about fertility preservation prior to treatment.
Driving and using machines
You should take special care when driving and using machines as you may feel tired or dizzy while taking Retsevmo.
Retsevmo contains sodium
This medicine contains less than 1 mmol sodium (23 mg) per tablet, that is to say essentially ‘sodium-free’.
3. How to take Retsevmo
Always take this medicine exactly as your doctor or pharmacist has told you, at the dose prescribed for you. Check with your doctor or pharmacist if you are not sure.
How much to take
Your doctor will prescribe the right dose for you. The maximum recommended dose is as follows:
- Less than 50 kg body weight: 120 mg twice daily.
- 50 kg body weight or greater: 160 mg twice daily.
Retsevmo is taken twice a day at about the same time every day, preferably in the morning and evening.
If you get certain side effects while you are taking Retsevmo your doctor may lower your dose or stop treatment temporarily or permanently.
You can take the tablets either with or without food. Swallow the tablet whole with a glass of water. Do not chew, crush or split the tablet before swallowing to ensure you receive the correct dose.
In case you have difficulty swallowing larger tablets whole, talk to your doctor about taking multiple smaller tablets instead to achieve your prescribed dose.
If you take more Retsevmo than you should
If you take too many tablets, or if someone else takes your medicine, contact a doctor or hospital for advice. Medical treatment may be necessary.
If you forget to take Retsevmo
If you vomit after taking the dose or forget a dose, take your next dose at your usual time. Do not take a double dose to make up for the forgotten or vomited dose.
If you stop taking Retsevmo
Do not stop taking Retsevmo unless your doctor tells you to.
If you have any further questions on the use of this medicine, ask your doctor or pharmacist.
4. Possible side effects
Like all medicines, this medicine can cause side-effects, although not everybody gets them.
Stop using Retsevmo and seek medical attention immediately if you notice any of the following symptoms of serious skin reactions:
- Reddish non-elevated, target-like or circular patches on the trunk, often with central blisters, skin peeling, ulcers of mouth, throat, nose, genitals and eyes. These serious skin rashes can be preceded by fever and flu-like symptoms [Stevens-Johnson syndrome (SJS)].
Contact your doctor immediately for any of the following:
Lung or breathing problems other than lung cancer with symptoms such as breathlessness, cough and raised temperature (which may affect more than 1 in 10 people) - Liver problems (which may affect more than 1 in 10 people and can be associated with abnormalities in liver blood tests, such as increased liver enzymes) including: yellow discoloration of the skin and eyes (jaundice), darkening of the urine, loss of appetite, nausea or vomiting, or pain on the upper right side of your stomach area - Allergic reaction typically shown by fever and muscle and joint pain followed by rash
(which may affect up to 1 in 10 people)
- High blood pressure (which may affect more than 1 in 10 people)
- Bleeding with symptoms such as coughing up blood
Tell your doctor, pharmacist or nurse if you notice any of the following side effects: Very common (may affect more than 1 in 10 people)
- Low blood levels of calcium
- Reduced number of white blood cells (e.g., lymphocytes, neutrophils, etc.) - Low blood levels of albumin
- Fluid retention that may cause swelling in your hands or ankles (oedema) - Diarrhoea
- Increased blood levels of creatinine in tests, which may indicate that kidneys are not working properly (renal disorders)
- Fatigue or tiredness
- Dry mouth
- Low blood levels of sodium
- Reduced number of blood platelets, which may cause bleeding and/or bruising - Rash
- Pain in the belly
- Constipation
- Low levels of haemoglobin, which may cause anaemia
- Low blood levels of magnesium
- Nausea (feeling sick)
- Headache
- Vomiting
- Bleeding symptoms
- Impotence
- Decreased appetite
- Abnormal ECG
- Low blood levels of potassium
- Dizziness
- Infection of the urinary tract
- Fever or high temperature
- Inflammation of the mucous membrane of the mouth
- Reduced thyroid activity
Common (may affect more than 1 in 100 people)
- Lymph fluid may build up in the lining of your lungs or your stomach cavity, which may cause breathing problems or enlargement of the stomach
- Irregular hip joint growth or damage causing pain or limp in patients < 18 years of age
Reporting of side effects
If you get any side effects, talk to your doctor or pharmacist. 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.
5. How to store Retsevmo
Keep this medicine out of the sight and reach of children.
Do not use this medicine after the expiry date which is stated on the blister and carton after “EXP”. The expiry date refers to the last day of that month.
This medicine does not require any special storage conditions.
Do not use this medicine if you notice that the inner seal is broken or shows signs of tampering.
Do not throw away any medicines via wastewater or household waste. Ask your pharmacist how to throw away medicines you no longer use. These measures will help protect the environment.
If the medicine becomes discolored or shows any other signs of deterioration, you should seek the advice of your pharmacist who will tell you what to do.
6. Contents of the pack and other information
What Retsevmo contains
The active substance is selpercatinib. Each film-coated tablet contains 40 mg selpercatinib.
The other ingredients are:
Tablet content: microcrystalline cellulose, mannitol, croscarmellose sodium,
hydroxypropylcellulose, sodium stearyl fumarate
- Film-coating: polyvinyl alcohol, titanium dioxide (E171), macrogol, talc, and black iron oxide (E172).
What Retsevmo looks like and contents of the pack
Retsevmo 40 mg is supplied as a light grey, round film-coated tablet debossed on one side with “5340” and debossed with “Ret 40” on the other.
Retsevmo is available in blister packs of 56 film-coated tablets.
Manufacturer
Lilly S.A.,
Avda. de la Industria 30,
28108 Alcobendas, Madrid,
Spain
Procured from within the EU and repackaged for the PL Holder: Abacus Medicine Ltd., Abbey House, 282 Farnborough Road,Farnborough, GU14 7NA, United Kingdom
Retsevmo 40 mg film-coated tablets
PL 45763/1919
POM
Retsevmo® is a registered trademark of Eli Lilly and Company.
For any information about this medicine, please contact the local representative of the Product Licence Holder:
Abacus Medicine Ltd.
tel: +44(0)2036301244
email: MedInfo@abacusmedicine.co.uk or
drugsafetyuk@abacusmedicine.co.uk
This leaflet was last revised on 29.06.2026.
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This medicine has been given ‘conditional approval’. This means that there is more evidence to come about this medicine.
The Medicines and Healthcare products Regulatory Agency will review new information on this medicine at least every year and this leaflet will be updated as necessary.