The CDK4/6 Inhibitor Dosing Knowledge (CDK) Study

Launched by AMERICAN SOCIETY OF CLINICAL ONCOLOGY · Apr 17, 2024

Keywords

ClinConnect Summary

The CDK Study is a clinical trial that aims to find out if a different way of giving certain cancer medications, known as CDK4/6 inhibitors, can help older patients with metastatic breast cancer (MBC) tolerate the treatment better and stay on it longer. The trial is specifically looking at patients aged 65 and older who have hormone receptor-positive (HR+) and HER2-negative MBC. Participants will be able to choose between two types of CDK4/6 inhibitors, palbociclib or ribociclib, along with an endocrine therapy, but will be randomly assigned to receive either the standard dose or a lower starting dose that can be increased if they handle it well.

To be eligible for the trial, participants must be 65 or older, have a specific type of MBC, and be suitable for the planned treatment. Those selected for the study can expect regular check-ins with their healthcare team to monitor how they are responding to the medication and to ensure they are managing any side effects. This trial is important as it may help doctors personalize treatment plans for older patients, making it easier for them to receive effective care for their cancer.

Gender

ALL

Eligibility criteria

• Inclusion Criteria:
• • 1. Hormone receptor positive (HR+) HER2 negative metastatic breast cancer. Cut-off values for positive/negative staining should be as per standard practice in accordance with ASCO/CAP (American Society of Clinical Oncology/College of American Pathologists) guidelines. Verification of histology is preferred at the time of recurrence and where not possible or necessary in the judgment of the treating physician, the study will accept histology from the initial diagnosis.
• • 2. Candidate for planned endocrine therapy in combination with 1st use of palbociclib or ribociclib, in the metastatic setting. The planned endocrine partner can be an aromatase inhibitor (letrozole, anastrozole, exemestane) or fulvestrant, selected through patient/provider choice.
• • 3. Aged 65 years or older
• • 4. Adequate bone marrow and organ function.
• • Absolute neutrophil count ≥ 1,000/µL
• • Platelets ≥ 100,000/µL
• • Hemoglobin ≥ 9g/dL
• • Total bilirubin ≤ 1.5 x institutional upper limit of normal (ULN) (participants with documented Gilbert's disease are allowed total bilirubin up to 5X ULN)
• • AST (SGOT)/ALT (SGPT) \<3 x institutional ULN, or ≤ 5 x ULN for subjects with documented metastatic disease to the liver.
• • Creatinine ≤ institutional ULN or creatinine clearance ≥ 30 mL/min/1.73 m2 for subjects with creatinine levels above institutional ULN.
• • Baseline QTc ≤ 480 ms (only for ribociclib patients)
• • 5. Ability to understand and the willingness to sign a written informed consent document.
• Exclusion Criteria:
• • 1. Previous treatment with a CDK4/6 inhibitor for metastatic breast cancer, or previous treatment within the past 12 months with a CDK4/6 inhibitor in the neo/adjuvant breast cancer setting.
• • 2. May have received no more than 30 days of the endocrine therapy agent planned as the partner to the CDK4/6 inhibitor in the study.
• • 3. Known history of intolerance or allergy to the planned agents used in this trial.
• • 4. Uncontrolled intercurrent illness that, as evaluated by the treating clinician, would hinder compliance with study requirements.
• • 5. Concurrent therapy with other investigational agents.
• • 6. Rapidly progressive brain metastases.
• • 7. Active or chronic Hepatitis B or C are eligible provided they meet liver function laboratory criteria and are not on medication with a known interaction with the study agents.
• • 9. Current use of drugs known to prolong the QT interval. 10. Prior or concurrent malignancies that are undergoing active treatment.