Abemaciclib
Abemaciclib is a targeted cancer therapy that inhibits CDK4 and CDK6, proteins that drive cancer cell division. It is approved for treating hormone receptor-positive (HR+), HER2-negative advanced or metastatic breast cancer, typically used in combination with hormone therapy.
Abemaciclib is an oral CDK4/6 inhibitor used to treat HR+/HER2- advanced breast cancer by blocking proteins that promote cancer cell growth.
Key facts at a glance
- ATC
- L01EF03
- RxNorm
- 1946825
- Generic
- Abemaciclib
- Class
- atc-l01
- Brands
- Verzenio
- Availability
- rx
- Lactation
- unknown
- Routes
- oral
- Forms
- tablet
- Regions
- US, EU, CN, JP
- Monitoring
- —
This page is for informational purposes only.
Do not use this information to diagnose yourself or to replace a physician's advice. Always consult a qualified healthcare provider before starting, stopping, or changing any medication. If you believe you are experiencing a medical emergency, call your local emergency number immediately.
Dosage and administration
- Usual dose
- 500mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 250mg twice daily
- Maximum
- consult physician
- Frequency
- every 12 hours
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
- Usual dose
- 400mg daily
- Maximum
- consult physician
- Frequency
- once daily
- Instructions
- Follow physician instructions
- Duration limits
- as prescribed
- Monitoring
- standard
Overdose information
Special Populations
8 groupspregnancy
all trimestersavoid if possible
avoid use during pregnancy unless benefits outweigh risks to the mother
regular fetal monitoring and ultrasound assessments
Use of this medication in this population requires careful consideration of risks and benefits.
lactation
breastfeedingavoid
do not breastfeed during treatment and for at least 3 weeks after last dose
infant monitoring for adverse effects
Use of this medication in this population requires careful consideration of risks and benefits.
pediatric_age
children and adolescentsnot established
safety and efficacy not established in pediatric patients
not applicable
geriatric
elderly 65 and olderno specific adjustment
use with caution, monitor for adverse effects particularly diarrhea and fatigue
regular monitoring of liver function and blood counts
Use with caution and monitor for adverse effects.
renal_impairment
mild moderateno initial adjustment
no initial dose adjustment needed for mild to moderate renal impairment
monitor renal function regularly
Use with caution and monitor for adverse effects.
renal_impairment
severeuse with caution
use with caution in severe renal impairment including end-stage renal disease
closely monitor renal function and for adverse effects
Use with caution and monitor for adverse effects.
hepatic_impairment
mild moderateno initial adjustment
no initial dose adjustment for mild to moderate hepatic impairment
monitor liver function tests regularly
Use with caution and monitor for adverse effects.
hepatic_impairment
severereduce dose
reduce dose to 100mg twice daily in severe hepatic impairment
frequent liver function monitoring
Use with caution and monitor for adverse effects.
Statistics and clinical data
FDA approval year
FDA approval date for Abemaciclib (Verzenio)
Drug class
Cyclin-dependent kinase 4/6 inhibitor - a targeted therapy drug
Common uses
Approved indications for Abemaciclib
Mechanism of action
Primary pharmacological mechanism
Treatment of HR+/HER2- advanced or metastatic breast cancer in combination with an aromatase inhibitor as initial endocrine-based therapy, or with fulvestrant for disease progression following endocrine therapy. Indicated for postmenopausal women and men.
Abemaciclib inhibits cyclin-dependent kinases 4 and 6 (CDK4/6), which are normally activated by cyclin D proteins. By blocking these kinases, it prevents phosphorylation of the retinoblastoma protein (Rb), thereby arresting the cell cycle and inhibiting tumor cell proliferation in estrogen receptor-positive cancers.
Take orally twice daily with or without food. Common side effects include diarrhea, fatigue, nausea, and neutropenia; patients should be monitored with regular blood counts. May cause fetal harm - effective contraception required during treatment. Dose reductions may be needed for toxicity management.
Contraindications
Conditions and patient states where this medication should be avoided or used with caution.
Do not use (1)
Known allergy to this medication or its components
Use caution (1)
Consult healthcare provider for benefits vs risks assessment
Official drug label
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This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed July 26, 2026. · Read our editorial policy