CDK4/6 inhibitors: The Devil is in the Detail
Tara Magge1, Sneha Rajendran1, Adam M Brufsky1
1Division of Hematology/Oncology, University of Pittsburgh School of Medicine, Pittsburgh, PA, 15213, USA.
Current Oncology Reports
|May 7, 2024
Summary
Cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) are standard for HR+/HER2- breast cancer. While effective, toxicities and cost limit use, and optimal timing requires further research.
Area of Science:
- Oncology
- Pharmacology
- Clinical Medicine
Background:
- Hormone receptor (HR)-positive, human epidermal growth factor receptor (HER)2-negative breast cancer is a major subtype.
- Cyclin-dependent kinase 4/6 inhibitors (CDK4/6i) have revolutionized treatment paradigms.
Purpose of the Study:
- To review the latest clinical evidence on CDK4/6 inhibitors in HR+/HER2- breast cancer.
- To summarize the efficacy and limitations of CDK4/6 inhibitors in both metastatic and early-stage disease.
Main Methods:
- Systematic review of recent clinical trials and real-world data.
- Analysis of progression-free survival and overall survival data.
- Evaluation of safety profiles and cost-effectiveness.
Main Results:
- CDK4/6 inhibitors (palbociclib, ribociclib, abemaciclib) combined with endocrine therapy (ET) improve progression-free survival in metastatic breast cancer (mBC).
- Ribociclib demonstrates an overall survival benefit in first-line mBC.
- Abemaciclib is approved for early breast cancer (eBC), with ribociclib showing promising early data for eBC.
Conclusions:
- CDK4/6 inhibitors are integral to treating HR+/HER2- breast cancer, both metastatic and high-risk early stages.
- Toxicity, financial burden, and optimal treatment sequencing remain key challenges.
- Further research is needed to refine the use of CDK4/6 inhibitors and address knowledge gaps.
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