OncoMatch/Clinical Trials/NCT05827081
Phase IIIb Study of Ribociclib + ET in Early Breast Cancer
Is NCT05827081 recruiting? Yes, currently enrolling (May 2026). This Phase 3 trial studies multiple treatments for early breast cancer.
Treatment: Ribociclib · Letrozole · Ansastrozole · Goserelin · Leuprolide · Exemestane — The purpose of this open-label, multicenter, phase IIIb, single-arm study is to characterize the efficacy and safety of the combination of ribociclib and standard adjuvant endocrine therapy (ET) on invasive breast cancer-free survival (iBCFS), in a close to clinical practice patient population with HR-positive (HR+), HER2-negative (HER2-), Anatomic Stage Group III, IIB, and a subset of Stage IIA Early Breast Cancer (EBC).
Check if I qualifyExtracted eligibility criteria
Cancer type
Breast Carcinoma
Biomarker criteria
Required: ESR1 overexpression (positive)
estrogen-receptor positive
Required: PR (PGR) overexpression (positive)
progesterone receptor positive
Required: HER2 (ERBB2) wild-type (IHC 0, 1+, or 2+ with negative ISH)
HER2- BC defined as a negative in situ hybridization test or an immunohistochemistry (IHC) status of 0, 1+ or 2+. If IHC is 2+, a negative in situ hybridization (FISH, CISH, or SISH) test is required
Disease stage
Required: Stage ANATOMIC STAGE GROUP III, ANATOMIC STAGE GROUP IIB, A SUBSET OF ANATOMIC STAGE GROUP IIA (AJCC 8th edition)
Excluded: Stage IV
Anatomic Stage Group III, or Anatomic Stage Group IIB, or A subset of Anatomic Stage Group IIA. Excluded: Stage IV according to AJCC 8th edition
Performance status
ECOG 0–2(Ambulatory, capable of self-care)
Prior therapy
Must have received: endocrine therapy (tamoxifen, toremifene) — neoadjuvant and/or adjuvant
Participants may have already received any standard neoadjuvant and/or adjuvant ET, including tamoxifen or toremifene at the time of informed consent signature, but enrollment should occur within 36 months of prior ET start date and participants should have at least 3 years remaining of endocrine adjuvant therapy
Lab requirements
Blood counts
adequate bone marrow function
Kidney function
adequate organ function
Liver function
adequate organ function
Cardiac function
QTcF interval at Screening < 450 msec; mean resting heart rate 50-99 bpm; no clinically significant, uncontrolled heart disease and/or cardiac repolarization abnormality
adequate bone marrow and organ function. ECG values: QTcF interval at Screening < 450 msec (QT interval using Fridericia's correction). Mean resting heart rate 50-99 beats per minute (determined from the ECG). Clinically significant, uncontrolled heart disease and/or cardiac repolarization abnormality [excluded].
Structured fields extracted by AI. May contain errors — verify against the official protocol.
US trial sites
- Central Alabama Research · Birmingham, Alabama
- Alaska Oncology and Hematology LLC · Anchorage, Alaska
- Western Reg MC-COH Phoenix · Goodyear, Arizona
- CARTI Cancer Center · Little Rock, Arkansas
- Onco Inst of Hope and Innovation · Cerritos, California
Showing up to 5 US sites. See all sites on ClinicalTrials.gov →
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