OncoMatch/Clinical Trials/NCT05996107
Study of Ribociclib Administered Concurrently With Postoperative Radiation Therapy in Patients With High-Risk, HR+/HER2- Breast Cancer
Is NCT05996107 recruiting? Yes, currently enrolling (May 2026). This Phase 1 trial studies Ribociclib for breast cancer.
Treatment: Ribociclib — The purpose of this research study is to determine the safety, tolerability and dose of Ribociclib when combined with adjuvant radiation in women with high-risk ER+ breast cancer. Once enrolled on study, patients will begin treatment with Ribociclib 400 mg daily at the same time as they initiate standard of care adjuvant radiation therapy- 50 Gy in 25 fractions or 42.56 Gy in 16 fractions +/- 10 Gy boost including comprehensive nodal. Paitents will continue treatment with Ribociclib for up to 6 weeks.
Check if I qualifyExtracted eligibility criteria
Cancer type
Breast Carcinoma
Biomarker criteria
Required: ESR1 overexpression (≥ 1% positivity)
ER and/or PR-positive (≥ 1% positivity as determined by local pathology laboratory)
Required: PR (PGR) overexpression (≥ 1% positivity)
ER and/or PR-positive (≥ 1% positivity as determined by local pathology laboratory)
Required: HER2 (ERBB2) wild-type
HER2-negative breast cancer
Disease stage
Grade: grade 3
Performance status
ECOG 0–1(Restricted strenuous activity)
Prior therapy
Must have received: chemotherapy — neoadjuvant or adjuvant
Patients must have completed chemotherapy (either in neoadjuvant or adjuvant setting).
Cannot have received: CDK4/6 inhibitor
Prior history of CDK4/6 inhibitor therapy.
Cannot have received: radiation therapy
Exception: prior radiation therapy to other sites is permissible
Prior history of radiation therapy to the chest wall and/or regional nodes is not allowed (but prior radiation therapy to other sites is permissible).
Lab requirements
Blood counts
Absolute neutrophil count ≥ 1.5 × 10^9/L; Platelets ≥ 100 × 10^9/L; Hemoglobin ≥ 9.0 g/dL; INR ≤1.5 (unless the patient is receiving anticoagulants and the INR is within the therapeutic range of intended use for that anticoagulant within 7 days prior to the first dose of study drug).
Kidney function
Estimated glomerular filtration rate (eGFR) ≥ 30 mL/min/1.73m2 according to MDRD formula.
Liver function
Total bilirubin < ULN except for patients with Gilbert's syndrome who may only be included if the total bilirubin is ≤ 3.0 × ULN or direct bilirubin ≤ 1.5 × ULN. AST < 2.5 × ULN, except for patients with liver metastasis, who are only included if the AST is < 5 × ULN. ALT < 2.5 × ULN, except for patients with liver metastasis, who are only included if the ALT is < 5 × ULN.
Cardiac function
QTcF interval at screening EKG ≤ 450ms; Mean resting heart rate 50-90 bpm; LVEF < 50% excluded.
Adequate baseline hematologic, hepatic and renal function as indicated below: ... QTcF interval at screening EKG ≤ 450ms (QT interval using Fridericia's correction). Mean resting heart rate 50-90 bpm (determined from the EKG).
Structured fields extracted by AI. May contain errors — verify against the official protocol.
US trial sites
- University of Michigan · Ann Arbor, Michigan
- University of Michigan Health West · Wyoming, Michigan
- UHCMC Seidman Cancer Center · Cleveland, Ohio
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