AzTrials
AzTrials

Metastatic Breast CancerPhase 3NCT06377852

The CDK4/6 Inhibitor Dosing Knowledge (CDK) Study

A Phase 3 study testing Palbociclib 125mg, Ribociclib 600mg and Ribociclib in people with Metastatic Breast Cancer, run by American Society of Clinical Oncology at 88 sites in United States.

Recruiting

Looking for participants now. Contact the study team or a site below to ask about taking part.

Sites and contacts
Official record
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Trial summary

The purpose of this study is to generate evidence on an alternative dosing strategy for CDK4/6 inhibitors to help more patients with Metastatic Breast Cancer (MBC) (age ≥ 60 years) tolerate side effects and stay on treatment longer, to derive the most clinical benefit from these drugs. Read more about this study

Who is it for?
Ages 60 years and older
Conditions the study is for
Metastatic Breast Cancer
What is being tested?
Palbociclib 125mg, Ribociclib 600mg and Ribociclib
Type of treatment
Pill or oral medicine
Could I receive a placebo?
No, everyone receives an active treatment
How many people
500 participants
Where
88 sitesUnited States
Study dates
29 Oct 2024to 1 Sep 2028
Phase
Phase 3
Are there results?
Not yet: the study is under way

Key requirements

Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.

  • Ages 60 years and older
  • All sexes
  • No healthy volunteers
  • Adult, Older adult

Who may be able to join

  • 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.
  • 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.
  • Aged 60 years or older
  • Adequate bone marrow and organ function. Laboratory values must be within normal institutional limits, or within ranges as indicated below, or demonstrate minor abnormalities that are deemed clinically non-significant by the investigator.
  • Absolute neutrophil count ≥ 1,000/µL
  • 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)
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  • AST (SGOT)/ALT (SGPT) <3 x institutional ULN, or ≤ 5 x ULN for subjects with documented metastatic disease to the liver.
  • Baseline QTc ≤ 480 ms (only for ribociclib patients)
  • Ability to understand and the willingness to provide informed consent. Note: Remote consent is allowed per institutional guidelines.

Who cannot join

  • 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.
  • Received greater than 60 days (in the metastatic setting) of the specific endocrine therapy agent planned as partner to the CDK4/6 inhibitor in the study at the time of randomization.
  • Known history of intolerance or allergy to the planned agents used in this trial.
  • Uncontrolled intercurrent illness that, as evaluated by the treating clinician, would hinder compliance with study requirements.
  • Concurrent therapy with other investigational agents or anticancer therapy beyond aromatase inhibitors or fulvestrant. Note: radiation is allowed at any time.
  • Rapidly progressive brain metastases. Note: only applies to patients with known brain metastases. Brain imaging not required for enrollment.
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  • 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.
  • Current use of drugs that have known potential to prolong the QT interval (e.g., antiarrhythmic drugs), for patients on ribociclib. Note: If concomitant use cannot be avoided, monitor ECG when initiating, during concomitant use, and as clinically indicated. Refer to crediblemeds.org as a resource.
  • Prior or concurrent malignancies that are undergoing active treatment.

Trial locations and contacts

88 sites in 1 country. Contact the study team or a site near you to ask about taking part.

Jackie Perez, MPH contact

571-483-1300

CDKstudy@asco.org

Cindy MacInnis, MBA contact

CDKstudy@asco.org

88 sites in 1 country

United States88 sites, 88 recruiting

  • Levine Cancer Institute

    Albemarle, North Carolina, 28001

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Lovelace Medical Center - Saint Joseph Square

    Albuquerque, New Mexico, 87102

    Zemmie Pollock, 505-727-3040, ZPollock@salud.unm.edu

    Bernard Tawfik, MD

    Recruiting

  • Lovelace Women's Hospital

    Albuquerque, New Mexico, 87109

    Zemmie Pollock, 505-727-3040, ZPollock@salud.unm.edu

    Bernard Tawfik, MD

    Recruiting

  • Presbyterian Kaseman Hospital

    Albuquerque, New Mexico, 87110

    Monique Robertson, 505-559-6100, mrobertso2@phs.org

    Bernard Tawfik, MD

    Recruiting

  • The University of New Mexico Comprehensive Cancer Center

    Albuquerque, New Mexico, 87131

    Crystal Pichette, 505-925-0380, cpichette@salud.unm.edu

    Bernard Tawfik, MD

    Recruiting

  • Emory University Winship Cancer Institute

    Atlanta, Georgia, 30322

    Kevin Kalinsky, MD, 404-778-1868, kevin.michael.kalinsky@emory.edu

    Kevin Kalinsky, MD

    Recruiting

  • The Jackson Laboratory (JAX) - Harold Alfond Center for Cancer Care

    Augusta, Maine, 04330

    Sandra Neptune, 207-626-4811, Sandra.Neptune@mainegeneral.org

    Erin Adler, DO

    Recruiting

  • University of Colorado Anschutz Medical Campus

    Aurora, Colorado, 80045

    Anna Lampart, 303-724-6231, anna.lamport@cuanschutz.edu

    Enrique Soto, MD, 303-724-6231, enrique.2.soto@cuanschutz.edu

    Recruiting

  • St. Joseph's Candler Bluffton Campus

    Bluffton, South Carolina, 29910

    Stephanie Reyes, 912-819-5723, smiths1@sjchs.org

    Leonard Henry, MD

    Recruiting

  • Northwest Medical Specialties

    Bonney Lake, Washington, 98391

    Jodi Thiel, (253) 720-8143, jthiel@southsoundcare.org

    Frank Senecal, MD

    Recruiting

  • Dana-Farber Cancer Institute

    Boston, Massachusetts, 02215

    Call, 877-338-7425

    Erica Mayer, MD

    Recruiting

  • The Jackson Laboratory (JAX) - Northern Light Cancer Care

    Brewer, Maine, 04412

    Laurie Lewis, 207-973-4249, llewis@northernlight.org

    Sarah Sinclair, DO

    Recruiting

  • Ironwood Cancer & Research Centers

    Chandler, Arizona, 85224

    Berenice Valdez, 480-890-7705, berenice.mendez@ironwoodcrc.com

    Sumeet Mendonca, MD

    Recruiting

  • Levine Cancer Institute

    Charlotte, North Carolina, 28204

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Levine Cancer Institute

    Charlotte, North Carolina, 28210

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Levine Cancer Institute

    Charlotte, North Carolina, 28211

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Levine Cancer Institute

    Charlotte, North Carolina, 28262

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Levine Cancer Institute

    Charlotte, North Carolina, 28277

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • University of Cincinnati Medical Center

    Cincinnati, Ohio, 45219

    Bonny Lami, 513-584-1239, lamiby@ucmail.uc.edu

    Mahmoud Charif, MD

    Recruiting

  • Levine Cancer Institute

    Concord, North Carolina, 28025

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Northwest Cancer Center

    Crown Point, Indiana, 46307

    Patricia Nelson, 219-836-6879, patricia.a.nelson@powershealth.org

    Michael Tallarico, MD

    Recruiting

  • UCHealth Cherry Creek Medical Center

    Denver, Colorado, 80206

    Anna Lamport, 303-724-6231, anna.lamport@cuanschutz.edu

    Enrique Soto, MD, enrique.2.soto@cuanschutz.edu

    Recruiting

  • Smilow Cancer Hospital Care Center - Derby

    Derby, Connecticut, 06418

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg, MD

    Recruiting

  • Northwest Cancer Center-Dyer

    Dyer, Indiana, 46311

    Patricia Nelson, 219-836-6879, patricia.a.nelson@powershealth.org

    Michael Tallarico, MD

    Recruiting

  • Englewood Hospital

    Englewood, New Jersey, 07631

    Dara Herman, 201-894-3944, Dara.Herman@ehmchealth.org

    Jill Morrison, MD

    Recruiting

  • Providence Medical Foundation

    Eureka, California, 95501

    Camille Shaffer, 707-521-3809, Camille.Shaffer@stjoe.org

    Jarrod Holmes, MD

    Recruiting

  • Smilow Cancer Hospital Care Center - Fairfield

    Fairfield, Connecticut, 06824

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg, MD

    Recruiting

  • Northwest Medical Specialties

    Federal Way, Washington, 98003

    Jodi Thiel, (253) 720-8143, jthiel@southsoundcare.org

    Frank Senecal, MD

    Recruiting

  • Levine Cancer Institute

    Forest City, North Carolina, 28043

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Dana-Farber Brigham Cancer Center Foxborough

    Foxborough, Massachusetts, 02035

    877-DF-TRIAL, 877-338-7425

    Sudha Bolla, MD

    Recruiting

  • Levine Cancer Institute

    Gastonia, North Carolina, 28054

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Northwest Medical Specialties

    Gig Harbor, Washington, 98332

    Jodi Thiel, (253) 720-8143, jthiel@southsoundcare.org

    Frank Senecal, MD

    Recruiting

  • Ironwood Cancer & Research Centers

    Gilbert, Arizona, 85297

    Berenice Valdez, 480-890-7705, berenice.mendez@ironwoodcrc.com

    Sumeet Mendonca, MD

    Recruiting

  • Smilow Cancer Hospital at Glastonbury

    Glastonbury, Connecticut, 06033

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg, MD

    Recruiting

  • Ironwood Cancer & Research Centers

    Glendale, Arizona, 85306

    Berenice Valdez, 480-890-7705, berenice.mendez@ironwoodcrc.com

    Sumeet Mendonca, MD

    Recruiting

  • Ironwood Cancer & Research Centers

    Goodyear, Arizona, 85395

    Berenice Valdez, 480-890-7705, berenice.mendez@ironwoodcrc.com

    Sumeet Mendonca, MD

    Recruiting

  • Smilow Cancer Hospital Care Center - Greenwich

    Greenwich, Connecticut, 06830

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg, MD

    Recruiting

  • Smilow Cancer Hospital Care Center - Guilford

    Guilford, Connecticut, 06437

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg, MD

    Recruiting

  • Smilow Cancer Hospital at Saint Francis

    Hartford, Connecticut, 06105

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg, MD

    Recruiting

  • UCHealth Highlands Ranch Hospital

    Highlands Ranch, Colorado, 80129

    Anna Lamport, 303-724-6231, anna.lamport@cuanschutz.edu

    Enrique Soto, MD, enrique.2.soto@cuanschutz.edu

    Recruiting

  • SC Cancer Specialists - Hilton Head at St. Joseph's/Candler

    Hilton Head Island, South Carolina, 29926

    Stephanie Reyes, 9128195723, smiths1@sjchs.org

    Leonard Henry, MD

    Recruiting

  • Liberty County Cancer Care

    Hinesville, Georgia, 31313

    Stephanie Reyes, 912-819-5723, smiths1@sjchs.org

    Leonard Henry, MD

    Recruiting

  • St. Mary Medical Center

    Hobart, Indiana, 46342

    Patricia Nelson, 219-836-6879, patricia.a.nelson@powershealth.org

    Michael Tallarico, MD

    Recruiting

  • Levine Cancer Institute

    Huntersville, North Carolina, 28078

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Penn Medicine - Lancaster General Hospital

    Lancaster, Pennsylvania, 17601

    Susan Tollett, 717-544-0511, susan.tollett@pennmedicine.upenn.edu

    Ramy Sedhom, MD

    Recruiting

  • Memorial Medical Center

    Las Cruces, New Mexico, 88011

    Deborah Brown, 575-521-1554, Deborah.Brown@LPNT.net

    Bernard Tawfik, MD

    Recruiting

  • Levine Cancer Institute

    Lincolnton, North Carolina, 28092

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Dana-Farber/New Hampshire Oncology-Hematology

    Londonderry, New Hampshire, 03053

    877-DF-TRIAL, 877-338-7425

    Jeanna Walsh, MD

    Recruiting

  • Levine Cancer Institute

    Matthews, North Carolina, 28104

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Baptist Memorial Healthcare

    Memphis, Tennessee, 38120

    Amber Stone, 901-226-1577, Amber.Stone@bmhcc.org

    Glenn Roma, MD

    Recruiting

  • Ironwood Cancer & Research Centers

    Mesa, Arizona, 85202

    Berenice Valdez, 480-890-7705, berenice.mendez@ironwoodcrc.com

    Sumeet Mendonca, MD

    Recruiting

  • Ironwood Cancer & Research Centers

    Mesa, Arizona, 85206

    Berenice Valdez, 480-890-7705, berenice.mendez@ironwoodcrc.com

    Sumeet Mendonca, MD

    Recruiting

  • Dana-Farber Cancer Institute Merrimack Valley

    Methuen, Massachusetts, 01844

    877-DF-TRIAL, 877-338-7425

    Ankur Mehta, MD

    Recruiting

  • Miami Cancer Institute

    Miami, Florida, 33176

    Kristianne Enriquez, 786-527-8537 ext. 57128, kristianne.enriquez@baptisthealth.net

    Reshma Mahtani, DO

    Recruiting

  • Dana-Farber Brigham Cancer Center at Milford Regional Medical Center

    Milford, Massachusetts, 01757

    877-DF-TRIAL, 8773387425

    Natalie Sinclair, MD

    Recruiting

  • Levine Cancer Institute

    Monroe, North Carolina, 28112

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Powers Health Cancer Research Foundation

    Munster, Indiana, 46321

    Patricia Nelson, 219-836-6879, patricia.a.nelson@powershealth.org

    Michael Tallarico, MD

    Recruiting

  • Smilow Cancer Hospital - Yale New Haven Health

    New Haven, Connecticut, 06510

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg, MD, MPH

    Recruiting

  • Yale University/Yale Cancer Center/Yale School of Medicine

    New Haven, Connecticut, 06510

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg, MD

    Recruiting

  • Capital Health Hematology Oncology Specialists

    Newton, Pennsylvania, 18940

    Tina Bergner, 609-537-7042, Tbergner@capitalhealth.org

    Pamella Crilley, DO

    Recruiting

  • Smilow Cancer Hospital Care Center - North Haven

    North Haven, Connecticut, 06473

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg, MD

    Recruiting

  • Northwest Medical Specialties

    Olympia, Washington, 98502

    Jodi Thiel, (253) 720-8143, jthiel@southsoundcare.org

    Frank Senecal, MD

    Recruiting

  • Pembroke Medical Oncology & St Joseph's/Candler Oncology Infusion Suite

    Pembroke, Georgia, 31321

    Stephanie Reyes, 912-819-5723, smiths1@sjchs.org

    Leonard Henry, MD

    Recruiting

  • Capital Health Medical Center - Hopewell

    Pennington, New Jersey, 08534

    Tina Bergner, 609-537-7042, Tbergner@capitalhealth.org

    Pamella Crilley, DO

    Recruiting

  • Penn Medicine - Perelman Center for Advanced Medicine

    Philadelphia, Pennsylvania, 19104

    Erin Freitas, 215-445-7277, erin.freitas@pennmedicine.upenn.edu

    Ramy Sedhom, MD

    Recruiting

  • Penn Medicine - Pennsylvania Hospital

    Philidelphia, Pennsylvania, 19106

    Clinical Research Team (RNs & CRCs), PAhemoncResearch@uphs.upenn.edu

    Ramy Sedhorn, MD

    Recruiting

  • Ironwood Cancer & Research Centers

    Phoenix, Arizona, 85028

    Berenice Valdez, 480-890-7705, berenice.mendez@ironwoodcrc.com

    Sumeet Mendonca, MD

    Recruiting

  • Penn Medicine - Princeton Health

    Plainsboro, New Jersey, 08536

    Florentin Racovitan, 609-853-6764, florentin.racovitan@pennmedicine.upenn.edu

    Ramy Sedhom, MD

    Recruiting

  • Miami Cancer Institute

    Plantation, Florida, 33324

    Dayana Deltejo, 954-837-1494, dayana.deltejo@baptisthealth.net

    Reshma Mahtani, DO

    Recruiting

  • Northwest Medical Specialties

    Puyallup, Washington, 98373

    Jodi Thiel, (253) 720-8143, jthiel@southsoundcare.org

    Frank Senecal, MD

    Recruiting

  • Presbyterian Rust Medical Center/Jorgensen Cancer Center

    Rio Rancho, New Mexico, 87124

    Andrea Yost, 505-559-6100, ayost3@phs.org

    Bernard Tawfik, MD

    Recruiting

  • Levine Cancer Institute

    Rock Hill, South Carolina, 29732

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Providence Medical Foundation

    Santa Rosa, California, 95403

    Camille Shaffer, 707-521-3809, Camille.Shaffer@stjoe.org

    Jarrod Holmes, MD

    Recruiting

  • Lewis Cancer and Research Pavilion

    Savannah, Georgia, 31405

    Stephanie Reyes, 912-819-5723, smiths1@sjchs.org

    Leonard Henry, MD

    Recruiting

  • Ironwood Cancer & Research Centers

    Scottsdale, Arizona, 85260

    Berenice Valdez, 480-890-7705, berenice.mendez@ironwoodcrc.com

    Sumeet Mendonca, MD

    Recruiting

  • Levine Cancer Institute

    Shelby, North Carolina, 28150

    Amanda Seifts, 980-442-2391, amanda.seifts@advocatehealth.org

    Neelam Desai, MD

    Recruiting

  • Candler Medical Oncology Practice and Infusion

    Statesboro, Georgia, 30458

    Stephanie Reyes, 912-819-5723, smiths1@sjchs.org

    Leonard Henry, MD

    Recruiting

  • Northwest Medical Specialties

    Tacoma, Washington, 98405

    Jodi Thiel, (253) 720-8143, jthiel@southsoundcare.org

    Frank Senecal, MD

    Recruiting

  • Smilow Cancer Hospital Care Center - Torrington

    Torrington, Connecticut, 06790

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg, MD

    Recruiting

  • Smilow Cancer Hospital Care Center - Trumbull

    Trumbull, Connecticut, 06611

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg, MD

    Recruiting

  • Northwest Cancer Center

    Valparaiso, Indiana, 46383

    Patricia Nelson, 219-836-6879, patricia.a.nelson@powershealth.org

    Michael Tallarico, MD

    Recruiting

  • Smilow Cancer Hospital Care Center - Waterbury

    Waterbury, Connecticut, 06708

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg

    Recruiting

  • Smilow Cancer Hospital - Waterford

    Waterford, Connecticut, 06385

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg, MD

    Recruiting

  • University of Cincinnati Medical Center - West Chester Hospital

    West Chester, Ohio, 45069

    Bonny Lami, 513-584-1239, lamiby@ucmail.uc.edu

    Mahmoud Charif, MD

    Recruiting

  • Penn Medicine - Chester County Hospital

    West Chester, Pennsylvania, 19380

    Caroline Depiano, 610-738-2522, caroline.depiano@pennmedicine.upenn.edu

    Ramy Sedhom, MD

    Recruiting

  • Smilow Cancer Hospital - Westerly

    Westerly, Rhode Island, 02891

    Carl Brown, 475-241-1065, carl.brown@yale.edu

    Maryam Lustberg, MD

    Recruiting

  • The University of Kansas Cancer Center

    Westwood, Kansas, 66205

    call or email to be connected, 913-945-7552, CTNurseNav@kumc.edu

    Ryan Rader, MD

    Recruiting

  • Dana-Farber Brigham Cancer Center at South Shore Health

    Weymouth, Massachusetts, 02190

    877-DF-TRIAL, 8773387425

    James Stoeckle, MD

    Recruiting

Other trials in United States

About this study

Official title: Comparing Oral Drug Dosing Strategies in Older Patients With Metastatic Breast Cancer to Maximize Tolerance and Reduce Discontinuation: The CDK4/6 Inhibitor Dosing Knowledge (CDK) Study

The purpose of this study is to generate evidence on an alternative dosing strategy for CDK4/6 inhibitors to help more patients with Metastatic Breast Cancer (MBC) (age ≥ 60 years) tolerate side effects and stay on treatment longer, to derive the most clinical benefit from these drugs.

The primary objective of the CDK Study is to compare time to treatment discontinuation (TTD) on the approved dosing for palbociclib (125 mg orally daily on days 1-21 of 28-day cycle) or ribociclib (600 mg orally daily on days 1-21 of 28-day cycle) vs. TTD using titrated dosing approach with the same schedule but starting at a lower dose of palbociclib (100 mg or 75 mg) or ribociclib (400 mg or 200 mg) and escalating the dose if well-tolerated in combination with provider/patient choice endocrine therapy (aromatase inhibitor (AI) or fulvestrant) in patients age 60 or older with HR+/HER2- MBC. The secondary and exploratory objectives will generate evidence needed to personalize treatment decisions by comparing patient-centric secondary outcomes and evaluating baseline factors.

Read more

Together with their treating physician, participants will choose the CDK4/6 inhibitor (palbociclib or ribociclib) and which endocrine therapy (aromatase inhibitor or fulvestrant) of their choice but will be randomized to either Arm 1 (indicated dosing) or Arm 2 (titrated dosing).

Note: Telehealth visits are allowed at any time per institutional guidelines. In addition, the study allows for remote consenting per institutional guidelines.

Read the detailed description

The CDK4/6 Inhibitor Dosing Knowledge Study (CDK Study) will study CDK4/6 inhibitor dosing regimens in patients 60 or older with Metastatic Breast Cancer (MBC). The overarching goal of this pragmatic, randomized trial is to compare an "indicated" dosing approach, as listed on the FDA-approved drug label, that starts at the full dose of a CDK4/6 inhibitor (palbociclib or ribociclib) with dose reduction based on tolerability versus a "titrated" dosing approach that starts at a lower dose of a CDK4/6 inhibitor and then titrates up to full dose as tolerated. CDK4/6 inhibitors will be given in combination with endocrine therapy (either an aromatase inhibitor (AI) or fulvestrant) based on the choice of the treating clinician.

The primary endpoint will be time to treatment discontinuation (TTD), defined as the time from randomization to last dose of the CDK4/6 inhibitor. The hypothesis is that starting low and escalating as tolerated will help older patients (> 60 years) stay on therapy longer. Eligibility criteria are broad to allow patients who are not typically included in clinical trials to participate, allowing for a more representative sample of participants. The investigators will conduct sub-group analyses based on age (60-64 years vs. 65-74 years vs. ≥75 years) and baseline frailty scores. This study builds upon the lessons learned from prior studies with CDK4/6 inhibitors. The investigators will augment the standard assessment of treatment toxicities assessed by the health care team with prospectively collected patient-reported outcomes data to better reflect how participants tolerate the different dosing approaches.

Being tested
Palbociclib 125mg, Ribociclib 600mg, Ribociclib, Palbociclib
Keywords
MBC
Medical subject headings
Breast Neoplasms

What participants receive

What participants receive. In a randomised study each person is assigned to one group by chance.

  • Palbociclib 125mgDrug

    Arm 1: Indicated dosing for palbociclib (125 mg orally daily on days 1-21 of 28-day cycle)

  • Ribociclib 600mgDrug

    Arm 1: Indicated dosing of ribociclib (600 mg orally daily on days 1-21 of 28-day cycle)

  • RibociclibDrug

    Arm 2: Titrated dosing approach with the same schedule but starting at a lower dose of ribociclib (400 mg or 200 mg) and escalating the dose if well-tolerated in combination with provider/patient choice of endocrine therapy.

  • PalbociclibDrug

    Arm 2: Titrated dosing approach with the same schedule but starting at a lower dose of palbociclib (100 mg or 75 mg) and escalating the dose if well-tolerated in combination with provider/patient choice of endocrine therapy.

Study groups in NCT06377852
Study groupRoleWhat they receive
Arm 1: Indicated DoseExperimentalArm 1 of the study is the indicated dosing regimen, provided in the FDA approved drug label: participants will start cycle 1 with either 125mg dose of palbociclib or 600mg dose of ribociclib, in combination with endocrine therapy (AI or fulvestrant).
Receives: Drug: Palbociclib 125mg; Drug: Ribociclib 600mg
Arm 2: Titrated DoseExperimentalArm 2 is the titrated dosing regimen: participants will start cycle 1 with either 100 mg or 75 mg dose of palbociclib or 400 mg or 200 mg dose of ribociclib, in combination with endocrine therapy (AI or fulvestrant). For cycle 2 and for subsequent cycles, escalation to the indicated dose will be based on treatment tolerance.
Receives: Drug: Ribociclib; Drug: Palbociclib

What is being measured

The primary outcome is the main question the study is designed to answer.

  1. Time to Treatment Discontinuation (TTD)

    Our primary outcome is time to CDK4/6 inhibitor discontinuation (TTD): the number of days between randomization and the last day the patient takes any dose of the same CDK4/6 inhibitor (regardless of drug holds, dose changes

    Measured: up to 48 months

Secondary outcomes (8)

  1. Toxicity (grade 3-4 AEs)

    Assessed in each arm of the study and study drug

    Measured: up to 48 months

  2. Event-Free survival (EFS)

    Assessed in each arm of the study and study drug

    Measured: up to 48 months

  3. Quality of life assessed by patient reported outcomes

    PROMIS-29 (3 domains of 12 questions, physical function, fatigue, participation in social activities), FACT-G Item GP5 (1 question)

    Measured: up to 48 months

  4. Time to dose reduction and escalation

    For titrated arm. Assessed in each arm of the study and study drug

    Measured: up to 48 months

  5. Reason for not escalating

    Assessed in each arm of the study and study drug

    Measured: up to 48 months

  6. Treatment received (missed doses, cumulative dose, etc.)

    Assessed in each arm of the study and study drug

    Measured: up to 48 months

  7. Healthcare utilization (ED visits, hospital admissions, etc.)

    ED visits, hospital admissions, etc., assessed in each arm of the study and study drug

    Measured: up to 48 months

  8. Body Mass Index

    weight and height will be combined to report BMI in kg/m^2

    Measured: up to 48 months

Timeline

From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.

  1. First posted22 Apr 2024
  2. Study start29 Oct 2024
  3. Primary completion31 Aug 2028 (estimated)
  4. Study completion1 Sep 2028 (estimated)

Resources

More details

For doctors and researchers: how the study is designed, who runs it, and its registry IDs.

Study design
Study type
Interventional
Phase
Phase 3
Primary purpose
Treatment
Allocation
Randomised
Intervention model
Parallel groups
Model description
500 patients will be enrolled, 250 per arm (Arm 1 being indicated dose, Arm 2 being titrated dose).
Masking
None (open label)
Enrolment
500 participants (estimated)
IDs, dates and publications
ClinicalTrials.gov ID
NCT06377852
Sponsor's protocol ID
Pro00075309
Status last verified
Oct 2026
First submitted
8 Apr 2024
Last updated
6 Oct 2026
Results posted
No
Data monitoring committee
Yes
FDA-regulated drug
Yes
FDA-regulated device
No
Individual data sharing
No

Questions about this trial

What is this clinical trial studying?

A Phase 3 study testing Palbociclib 125mg, Ribociclib 600mg and Ribociclib in people with Metastatic Breast Cancer, run by American Society of Clinical Oncology at 88 sites in United States.

The full registered description is in the About this study section and the official record.

Who may be eligible to take part?

The sponsor lists 9 inclusion and 9 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.

Is this clinical trial currently recruiting?

The record says: looking for participants now, as of the sponsor's last update on 6 Oct 2026. Status can change between updates, so confirm with the study contact before making plans.

Where is the study taking place?

The record lists 88 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.

What are the possible benefits and risks?

They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.

What does this phase mean?

Phase 3 studies compare the treatment with the current standard treatment or a placebo in a large group, to confirm how well it works and watch for side effects.

Not every study follows the same path, and some studies (observational studies, device studies) have no phase.

Are results available for this study?

This study is still under way. Results are not available in the source record yet.

How can a doctor refer a patient or contact the research team?

Contact Jackie Perez, MPH (571-483-1300, CDKstudy@asco.org), or a site near the patient. AzTrials does not enrol participants or take referrals.

What does the primary outcome measure?

Time to Treatment Discontinuation (TTD) (time frame: up to 48 months). It is what the study was designed to measure, not a finding.

Where can I read the original study information?

On the ClinicalTrials.gov record for NCT06377852.

Does a listing mean the treatment is approved or proven to work?

No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.

How often is this information updated?

AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Oct 2026.

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