Abemaciclib: Uses, Interactions and Safety
Uses
Abemaciclib inhibits CDK4 and CDK6 and is used with endocrine therapy for selected hormone receptor-positive, HER2-negative breast cancers. These include high-risk early disease and advanced or metastatic disease under the relevant eligibility criteria. The Turkish product reviewed is Yulareb; international brand names and available strengths can differ.
Administration
Swallow film-coated tablets whole with or without food and follow the specialist’s written regimen. Do not crush, split or chew them. This medicine has a different treatment pattern from other CDK4/6 inhibitors, so schedules should not be exchanged between products. Contact the team about interruptions, vomiting or an inability to keep medicines down.
Safety
Diarrhoea often starts early and can lead to dehydration. Follow the diarrhoea plan supplied before treatment and contact the team at the first loose stool. Urgent assessment is needed for fever, inability to drink, jaundice, unilateral leg swelling, sudden chest pain or breathlessness. Blood clots, serious infection, liver injury and lung inflammation are important risks. Blood counts and liver tests are monitored.
Interactions
Strong CYP3A inhibitors can raise exposure and generally require avoidance or specialist adjustment. Moderate inhibitors warrant closer toxicity monitoring. Strong inducers can reduce anticancer efficacy. Abemaciclib inhibits renal transporters, which can raise serum creatinine without necessarily reducing filtration; unexpected results still require assessment. Its metformin study showed a modest exposure increase rather than a contraindication. Loperamide is an established supportive treatment for diarrhoea, and the studied pharmacokinetic change was not clinically meaningful. Narrow therapeutic index P-gp substrates deserve review.
Pregnancy and breastfeeding
Abemaciclib is not recommended during pregnancy. Use the recommended effective contraception during treatment and for at least three weeks afterwards. The effect on systemic hormonal contraception is uncertain and should be discussed. Do not breastfeed during treatment.
Adverse effects
Diarrhoea, infections, low blood counts, fatigue, nausea, vomiting, decreased appetite and hair thinning are common. Report symptoms early so supportive treatment and any necessary prescription changes can be arranged.
Sources
Additional verified references
The linked Turkish profile contains the medicine record and its documented interaction list.