Cabometyx (cabozantinib) is a targeted cancer medicine that works by blocking proteins involved in tumour growth and the formation of new blood vessels that feed tumours. It belongs to a class of medicines called tyrosine kinase inhibitors (TKIs).

Cabometyx is used to treat:

• Advanced kidney cancer (renal cell carcinoma), either as a first-line treatment or after prior therapy
• Liver cancer (hepatocellular carcinoma) in people who have previously been treated with sorafenib
• Differentiated thyroid cancer that has progressed and can no longer be treated with radioactive iodine

How it works:

Cancer cells rely on multiple signalling pathways to grow, spread, and develop their own blood supply. Cabozantinib blocks several of these pathways at once, including VEGFR, MET, and AXL. By targeting multiple pathways simultaneously, it can be effective in cancers that have become resistant to other single-target therapies.

Your dose:

Your doctor will prescribe the dose appropriate for your cancer type and overall health. The usual starting dose is 60mg once daily, though doses of 40mg or 20mg may be used if side effects require a reduction. Always follow your doctor's instructions.

How to take it:

• Take Cabometyx at the same time every day
• Do not eat for at least 2 hours before and at least 1 hour after taking Cabometyx. Food, particularly high-fat meals, significantly increases the amount of medicine your body absorbs and may increase side effects
• Swallow the tablets whole. Do not crush or chew them
• Avoid grapefruit, grapefruit juice, and Seville oranges during treatment

Before you start:

• Tell your doctor about all other medicines, vitamins, and supplements you take
• Let your doctor know if you have any history of high blood pressure, bleeding problems, blood clots, heart conditions, liver disease, or recent surgery
• Tell your doctor if you are pregnant, planning to become pregnant, or breastfeeding. Effective contraception is required during and after treatment

Ongoing check-ups:

Regular blood pressure monitoring, blood tests (liver function, thyroid, kidney), and imaging will be arranged during treatment. Blood pressure should be well controlled before and during therapy.

• If you remember more than 12 hours before your next scheduled dose: take the missed dose as soon as you can
• If it is less than 12 hours until your next dose: skip the missed one and continue your regular schedule
• Never take two doses at once

Contact your doctor or pharmacist if you are unsure.

If you think you have taken more than prescribed, call 000 or go to your nearest emergency department straight away.

Signs that something might be wrong include:

• Severe diarrhoea or stomach pain
• Very high blood pressure
• Unusual bleeding

• Store below 30°C
• Keep in the original packaging, away from moisture and light
• Do not store in the bathroom
• Keep out of reach of children and pets

Side effects are common with Cabometyx.

Many can be managed with dose adjustments or supportive care.

• Diarrhoea: Very common. Stay well hydrated. Your doctor may prescribe anti-diarrhoea medicines
• Fatigue: Common. Rest when needed and let your care team know if it is impacting daily life
• High blood pressure: Your blood pressure will be checked regularly. You may need blood pressure medication during treatment
• Palmar-plantar erythrodysaesthesia (hand-foot syndrome): Redness, pain, or blistering on the palms or soles. Regular moisturising and avoiding pressure on affected areas can help. Tell your doctor if it becomes severe
• Nausea and decreased appetite: Small, frequent meals and staying hydrated may help
• Mouth sores: Rinse with plain water or a gentle alcohol-free mouthwash
• Liver changes: Elevated liver enzymes are possible. Regular monitoring is essential
• Blood clots or bleeding: Cabozantinib can affect blood vessel integrity. Tell your doctor immediately if you develop severe pain, swelling in a limb, chest pain, or unusual bleeding
  

Contact your doctor or pharmacist if any side effect concerns you.

Tell your doctor and pharmacist everything you are taking. Key interactions include:

• Strong CYP3A4 inhibitors (such as ketoconazole, clarithromycin, ritonavir): Can increase cabozantinib levels significantly
• Strong CYP3A4 inducers (such as rifampicin, phenytoin, St John's Wort): Can reduce how well Cabometyx works
• Blood thinners (such as warfarin): Cabometyx can affect bleeding risk. Close monitoring is needed
• Grapefruit: Avoid throughout treatment as it can increase cabozantinib levels in your blood

Never start, stop, or change any medicine without speaking to your doctor first.

Do I really need to fast before taking Cabometyx?

Yes. Taking Cabometyx with food, especially a high-fat meal, significantly increases the amount absorbed into your bloodstream, which raises the risk of side effects. Taking it on an empty stomach (nothing to eat for 2 hours before and 1 hour after) gives you the most predictable dose.

What is hand-foot syndrome and how do I manage it?

Hand-foot syndrome causes redness, swelling, pain, and sometimes blistering on the palms of your hands and soles of your feet. Moisturise affected areas frequently, wear comfortable shoes with cushioning, avoid hot water and friction, and tell your doctor early if symptoms appear so they can adjust your dose if needed.

How long will I take Cabometyx?

Treatment continues as long as your cancer is responding and side effects are manageable. Your doctor will monitor your response through regular scans and blood tests.

Ace provides accurate and independent information medically reviewed on prescription medications. This material is provided for educational purposes only and is not intended for medical advice, diagnosis or treatment.