Episode 333: Pharmacology 101: CDK Inhibitors

“CDK4/6 inhibition is considered to be a milestone in the realm of targeted breast cancer therapy. The combination of CDK4/6 inhibitors with the endocrine therapy has really emerged as the foremost therapeutic modality for patients diagnosed with hormone receptor–positive, HER2-negative, advanced breast cancer,” ONS member Teresa Knoop, MSN, RN, AOCN^®-emeritus, independent nurse consultant in Nashville, TN, told Jaime Weimer, MSN, RN, AGCNS-BS, AOCNS^®, manager of oncology nursing practice at ONS, during the latest episode in our series about anticancer drug classes.

Music Credit: “Fireflies and Stardust” by Kevin MacLeod

Licensed under Creative Commons by Attribution 3.0 

Earn 0.75 contact hours of nursing continuing professional development (NCPD) by listening to the full recording and completing an evaluation at courses.ons.org by October 18, 2025. The planners and faculty for this episode have no relevant financial relationships with ineligible companies to disclose. ONS is accredited as a provider of nursing continuing professional development by the American Nurses Credentialing Center’s Commission on Accreditation.

Learning outcome: Learners will report an increase in knowledge related to CDK inhibitors.

Episode Notes 

• The NCPD activity for this episode has expired, but you can still earn NCPD through many other ONS Podcast episodes. Find a full list of opportunities.
• Oncology Nursing Podcast^™ episodes:
  • Pharmacology 101 series
  • Episode 329: Pharmacology 101: BRAF Inhibitors
  • Episode 313: Cancer Symptom Management Basics: Other Pulmonary Complications
  • Episode 295: Cancer Symptom Management Basics: Pulmonary Embolism, Pneumonitis, and Pleural Effusion
  • Episode 80: Patients Need Checkpoint Inhibitor Education
  • Episode 5: New Guidelines for Managing Immunotherapy-Related Adverse Events
• ONS Voice articles:
  • Combination CDK4/6 and Fulvestrant Has Survival Benefits in Late-Stage Breast Cancer
  • FDA Approves Inavolisib With Palbociclib and Fulvestrant for Endocrine-Resistant, PIK3CA-Variant, HR-Positive, HER2-Negative, Advanced Breast Cancer
  • FDA Approves Ribociclib With an Aromatase Inhibitor and Ribociclib and Letrozole Co-Pack for Early High-Risk Breast Cancer
  • FDA Expands Early Breast Cancer Indication for Abemaciclib With Endocrine Therapy
  • FDA Warns of Rare Lung Inflammation With Certain CDK4/6 Inhibitors
  • Manage Immunotherapy-Related Diarrhea and Colitis
  • Oncology Drug Reference Sheet: Ribociclib
  • The Case of the CTCAE Assessment for CDK4/6 Adverse Events
• ONS book: Clinical Guide to Antineoplastic Therapy: A Chemotherapy Handbook (fourth edition)
• Clinical Journal of Oncology Nursing article: Targeted Therapies: Treatment Options for Patients With Metastatic Breast Cancer
• ONS Symptom Intervention: Prevention of Infection: General 
• ONS Breast Cancer Learning Library
• ONS CDK4/6 Administration Checklist
• ONS Oral Anticancer Medication Toolkit 
• Breastcancer.org
• Susan G. Komen: CDK4/6 Inhibitors
• Ibrance^® (palbociclib) patient site
• Kisqali^® (ribociclib) patient site
• Verzenio^® (abemaciclib) patient site

To discuss the information in this episode with other oncology nurses, visit the ONS Communities. 

To find resources for creating an Oncology Nursing Podcast club in your chapter or nursing community, visit the ONS Podcast Library.

To provide feedback or otherwise reach ONS about the podcast, email [e-mail].

Highlights From This Episode

“Common toxicity among this class of agents are things like nausea/vomiting, diarrhea, fatigue. All three are associated with low white blood cell counts, which we know as neutropenia, which can cause an increased risk of infection.” TS 10:46

“All three of these CDK4/6 inhibitors are pills taken by mouth, and in most cases they’re all given along with endocrine therapy treatments. So, patients will be taking more than one drug. Teach patients how they will take their medication. And the frequency among the three drugs may vary.” TS 13:33

“Patients and caregivers need to know the time of day to take the pills, whether they need to be taken with or without food, or what to do if they miss a dose. We need to help them with a system for organizing the medications. They may find it helpful to use a pill organizer or set reminders on their smartphone, their smartwatch, their computer.” TS 14:29 

“Pharmacy and nursing, in my experience, collaborate greatly by determining those drug–drug and drug–food interactions. It is so crucial in determining those interactions and educating our patients because we have to remind patients at each appointment and review these drugs and foods and other things they may be taking, at each appointment. And that often can be done by either pharmacists or nurses or both in collaboration.” TS 23:29

“This class of drug is generally well-tolerated, and I do want nurses to know that that we can help patients with these side effects. And they are generally well-tolerated with appropriate management.” TS 30:55