Clinical trial Recruiting at 4 sites Phase 1 Interventional Ages 60 and up Women only

Combining pre-operative radiation with Abemaciclib and Letrozole for breast cancer

Official title: RADIANT Study: Pre-op Radiation With Abemaciclib Andletrozole in Early Stage Breast Cancer

Run by Rutgers, The State University of New Jersey · NCT06139107 · Data updated 2026-11-12

This study is testing if giving radiation therapy together with two medications, Abemaciclib and Letrozole, is safe and effective for people with hormone receptor positive/HER2 negative breast cancer before surgery.

More Breast Cancer trials

Quick facts

PhasePhase 1
Study typeInterventional
Ages60 Years and up
SexWomen only
Enrollment15 (estimated)
SponsorRutgers, The State University of New Jersey
Academic / other
Drugs / interventionschemotherapy, radiation
Locations4 sites (Belleville, New Jersey and 3 other locations)
StatusRecruiting
StartedAugust 22, 2024
Main results expectedSeptember 30, 2026
Study endsSeptember 30, 2032
Registry record updatedNovember 14, 2025
Trial IDNCT06139107 on ClinicalTrials.gov

Is this trial a fit for you?

Likely a good fit

Ideal candidates are post-menopausal women with HR+/HER2- breast cancer who have a tumor size of at least 1.5 cm and meet specific eligibility criteria.

Probably not a fit

Patients with metastatic disease or those who do not meet the inclusion criteria will not benefit from this study.

A plain-English reading of the study's rules. Only the study team can confirm whether you qualify.

What this trial studies

This phase 1b study investigates the safety and feasibility of using pre-operative radiation therapy alongside CDK4/6 inhibitors in patients with hormone receptor positive/HER2 negative breast cancer. The research focuses on the concurrent administration of these treatments to assess their combined effects and tolerability. Participants will undergo thorough evaluations, including clinical assessments and imaging studies, to monitor treatment responses and any potential side effects. The goal is to gather valuable data that could inform future clinical applications of this combination therapy.

Why it matters

Potential benefit: If successful, this approach could improve treatment outcomes for patients with HR+/HER2- breast cancer by providing a novel therapeutic strategy.

How similar studies have gone: While this approach is novel, other studies have explored CDK4/6 inhibitors in breast cancer, indicating potential for success in this area.

Who can join: the full rules

Show full inclusion / exclusion criteria
Inclusion Criteria:

* Histologically and/or cytologically confirmed diagnosis of invasive (ductal, lobular or mixed histology), Clinically inapparent tumor that is not palpable. (cT1-T2N0)disease. Minimum tumor size of 1.5 cm
* Expression of ER or progesterone receptors (PR)and negative expression of HER2 per American Society of Clinical Oncology, (ASCO) Common Alerting Protocol (CAP) guidelines
* Oncotype diagnosis (DX) Breast Recurrence score of less than 25 on core biopsy specimen
* Post-menopausal status defined:
* age \<60 with amenorrhea for at least 12 months in the absence of prior chemotherapy, tamoxifen, toremifene, or ovarian suppression and estradiol and FSH (follicle stimulating hormone) in postmenopausal range.
* No clinical suspicion of metastasis disease
* Eastern Cooperative Oncology Group (ECOG) performance status of follicle stimulating hormone (PFS) ≤2
* Eligible to undergo surgery, either lumpectomy or mastectomy for local treatment of the breast cancer
* Able to swallow oral medications
* Adequate organ function for all of the following:

Absolute Neutrophil (ANC) \>1.5 x 10/L Platelets \>100 x 10/L Hemoglobin \>8 g/dL - May receive erythrocyte transfusions to achieve this level Total Bilirubin \<1.5 x Upper Limit of Normal (ULN) Alanine Aminotransferase (ATL) and Aspartate Aminotransferase (AST) \<3 x ULN

* HR positive/HER2 -negative breast cancers are allowed as long as no other exclusions exist

Exclusion Criteria:

* History of ipsilateral breast cancer
* Prior treatment with CDK4/6 inhibitors or aromatase inhibitors
* History of chest wall or ipsilateral breast radiation
* Inflammatory breast cancer
* Needs neoadjuvant chemotherapy
* Presence of distant metastatic disease
* Contraindication for surgery
* Uncontrolled hypertension (systolic blood pressure \>190 mm Hg or diastolic blood pressure \>100 mm Hg)
* Any condition including the presence of laboratory abnormalities, which, in the opinion of the investigator places the subject at unacceptable risk if he/she were to participate in the study
* Life expectancy \< 12 weeks
* History of allergy or hypersensitivity to any of the study drugs
* Any significant medical condition, laboratory abnormality, or psychiatric illness
* Serious and/or uncontrolled preexisting medical condition
* Has had major surgery within 14 days prior to enrollment
* Has received an experimental treatment in a clinical trial within the last 30 days or 5 half-lives, whichever is longer, prior to enrollment, or is currently enrolled in any other type of medical research
* Has active systemic bacterial infection
* Personal history of any of the following conditions: syncope of cardiovascular etiology, ventricular arrhythmia of pathological origin (including, but not limited to, ventricular tachycardia and ventricular fibrillation), or sudden cardiac arrest

Where it's running

  • RWJBarnabas Health Clara Maas Medical Center
    Belleville, New Jersey, United States
    Recruiting
  • Cooperman Barnabas Medical Center
    Livingston, New Jersey, United States
    Recruiting
  • Rutgers Cancer Institute of New Jersey
    New Brunswick, New Jersey, United States
    Recruiting
  • RWJBarnabas Health - Robert Wood Johnson University Hospital Somerset
    Somerville, New Jersey, United States
    Recruiting

Study contacts

  • Principal investigator: Mridula A George, MD — Cancer Institute of New Jersey Rutgers
  • Study coordinator: Mridula A George, MD
  • Email: mridula@cinj.rutgers.edu
  • Phone: 732-235-9081

Similar studies

Other studies for the same condition or treatment. Recruiting studies are listed first.

How to take part

  1. Review the eligibility criteria above with your treating physician.
  2. Check the official listing on ClinicalTrials.gov for the latest contact details and recruitment status.
  3. Contact the study coordinator or principal investigator to ask for pre-screening. Pre-screening is free and never obligates you to enroll.
Last reviewed 2026-11-14 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.