Indications
Palbociclib is a targeted cancer medicine taken by mouth. It is used for hormone receptor-positive (HR-positive), HER2-negative breast cancer that is advanced or has spread to other parts of the body. It is given together with hormone therapy: an aromatase inhibitor such as Letrozole, or Fulvestrant. It is prescribed and monitored by a cancer specialist.
How It Works
Palbociclib blocks two proteins called CDK4 and CDK6, which help cancer cells divide. Blocking them slows or stops the growth of the cancer. Combined with hormone therapy, it works better than hormone therapy alone.
Dosage and Administration
Take exactly as prescribed. It is usually taken once a day for 21 days, followed by 7 days without it, making a 28-day cycle. The doctor may lower the dose or pause treatment depending on blood counts and side effects.
- Take at about the same time each day. Capsules are taken with food; tablets can be taken with or without food. Follow the leaflet for your product.
- Swallow whole; do not chew, crush or open.
- If you miss a dose or vomit, do not take an extra dose; take the next dose at the usual time.
- Avoid grapefruit and grapefruit juice.
Interactions
- Strong CYP3A inhibitors such as Clarithromycin, Itraconazole, Ketoconazole, Ritonavir and Voriconazole raise Palbociclib levels; they should be avoided or the dose reduced.
- Rifampicin, Carbamazepine, Phenytoin and St John’s wort lower its levels and should be avoided.
- It may raise levels of some medicines, such as Midazolam, Cyclosporine, Tacrolimus and Simvastatin.
Tell the specialist about every medicine and herbal product you take.
Contraindications
- Allergy to Palbociclib or any ingredient
- Products containing St John’s wort
Side Effects
Very common: low white blood cells (neutropenia), infections, tiredness, nausea, sore mouth, hair thinning, diarrhoea, anaemia, low platelets, rash and reduced appetite.
Get urgent medical help if you notice:
- Fever, chills or other signs of infection
- New or worsening cough, shortness of breath or chest pain (possible lung inflammation)
- Unusual bleeding or bruising
- Pain, swelling or warmth in a leg, or sudden breathlessness (possible blood clot)
Pregnancy and Lactation
Palbociclib may harm an unborn baby. Women who could become pregnant should use effective contraception during treatment and for some weeks after the last dose, as the doctor advises. Men with partners who could become pregnant should also use contraception. Do not breastfeed during treatment and for a period after it, as advised by the doctor. It may affect male fertility.
Precautions and Warnings
- Blood counts are checked before each cycle and more often at the start of treatment.
- Tell the doctor about liver or kidney problems, or any current infection.
- Report any breathing problems promptly.
- It can cause tiredness; take care when driving.
Overdose
If too much is taken, contact the doctor or go to hospital. Overdose may cause nausea, tiredness and low blood counts. There is no specific antidote; treatment is supportive.
Therapeutic Class
Antineoplastic (cancer medicine); CDK4/6 inhibitor.
Storage
Store below 30°C in a dry place, away from light, in the original pack and out of the reach of children.
Prepared by the Oshud Alo team from standard drug references. For information only; always follow your doctor's advice.