abemaciclib at a glance
Medicine class
Cyclin-dependent kinase 4 and 6 inhibitor
Usual role
Treatment of selected early, locally advanced or metastatic HR-positive, HER2-negative breast cancers
Food
Tablets may be taken with or without food; avoid grapefruit
Key monitoring
Blood counts, liver tests and assessment for diarrhoea, infection, lung inflammation and blood clots
What is abemaciclib used for?
The selected UK product is licensed with endocrine therapy for:
Adults with HR-positive, HER2-negative, node-positive early breast cancer at high risk of recurrence.
Women with HR-positive, HER2-negative locally advanced or metastatic breast cancer, as initial endocrine-based therapy or after previous endocrine therapy.
Premenopausal or perimenopausal women, with ovarian suppression as specified in the product licence.
How does abemaciclib work?
Abemaciclib inhibits CDK4 and CDK6, preventing susceptible cancer cells from progressing into DNA replication and suppressing tumour-cell growth.
How to take abemaciclib
Follow the schedule supplied by the specialist cancer team.
Take with or without food.
Avoid grapefruit and grapefruit juice.
Swallow tablets whole; do not chew, crush or split them.
If vomiting occurs after a tablet, do not take a replacement; continue at the next scheduled time.
abemaciclib side effects
Common or expected effects
- Diarrhoea
- Infections
- Reduced white blood cells, red blood cells or platelets
- Tiredness
- Nausea or vomiting
- Reduced appetite
- Hair loss
- Headache, dizziness or altered taste
- Rash or itching
- Raised liver enzymes
Get urgent medical advice
- Fever or infection with reduced white blood cells
- Severe or persistent diarrhoea, especially with dehydration
- New or worsening cough or breathlessness, which may indicate pneumonitis or interstitial lung disease
- A swollen, painful limb, chest pain or breathlessness, which may indicate a blood clot
- Sudden weakness, speech difficulty or severe chest pain, which may indicate an arterial clot
- Jaundice, dark urine or marked upper abdominal pain, which may indicate severe liver injury
- Rare severe skin reactions, including target-like red patches
abemaciclib in pregnancy
Abemaciclib is not recommended during pregnancy because animal studies indicate reproductive toxicity and human pregnancy data are unavailable. People who could become pregnant should discuss highly effective contraception with their specialist and continue it for at least three weeks after treatment ends. Its effect on systemic hormonal contraceptives is uncertain.
abemaciclib while breastfeeding
Breastfeeding is not recommended during treatment. It is unknown whether abemaciclib enters human milk, and risk to a breastfed child cannot be excluded.
abemaciclib interactions
The cancer team and pharmacist should review prescribed, over-the-counter and herbal products before and during treatment.
Strong CYP3A4 inhibitors, including clarithromycin, itraconazole, ketoconazole, posaconazole, voriconazole and lopinavir/ritonavir
These can substantially increase abemaciclib exposure and toxicity, so concurrent use should generally be avoided or specialist-managed.
Strong CYP3A4 inducers, including rifampicin, carbamazepine, phenytoin and St John’s wort
These can markedly reduce abemaciclib exposure and potentially reduce its effectiveness, so concurrent use should be avoided.
Grapefruit and grapefruit juice
These may increase abemaciclib concentrations and should be avoided.
Common questions about abemaciclib
Answers are fully visible for fast scanning and source review.
Is abemaciclib chemotherapy?
It is a targeted anticancer treatment rather than conventional cytotoxic chemotherapy. It inhibits CDK4 and CDK6.
Can men receive abemaciclib?
The UK early-breast-cancer indication applies to adults and can include men. The selected locally advanced or metastatic indication is specifically licensed for women.
Can the tablets be crushed or split?
Sources
These sources were used to prepare and review this medicine page.
Prepared and reviewed by the iatroX editorial team.