biostudies-literatureUnknown11(11)Fasching PA<h4>Importance</h4>Ribociclib plus a nonsteroidal aromatase inhibitor (NSAI) has demonstrated a statistically significant invasive disease-free survival (iDFS) benefit over NSAI alone in patients with hormone receptor-positive/ERBB2 (formerly HER2)-negative early breast cancer. Evaluating the efficacy and safety of adjuvant ribociclib beyond the planned 3-year treatment period is critical for understanding the long-term impact on recurrences.<h4>Objective</h4>To evaluate efficacy and safety of adjuvant ribociclib in an exploratory 4-year analysis of the NATALEE (New Adjuvant Trial With Ribociclib [LEE011]) randomized clinical trial, with all patients no longer receiving ribociclib treatment.<h4>Design, setting, and participants</h4>This exploratory analysis of an international, open-label,JAMA oncology1364-1372https://www.ebi.ac.uk/biostudies/studies/S-EPMC12464853biostudies-literatureRibociclib Plus Endocrine Therapy in Hormone Receptor-Positive/ERBB2-Negative Early Breast Cancer: 4-Year Outcomes From the NATALEE Randomized Clinical Trial.PMC12464853Zarate JPHortobagyi GNStroyakovskiy DYardley DAHurvitz SAFasching PAFresco RBardia AMoroose RChia SBarrios CHuang CSLi ZVisco FXu BWaters SSlamon DJUntch MMartin MLoi SCrown JIm SAfalseRibociclib Plus Endocrine Therapy in Hormone Receptor-Positive/ERBB2-Negative Early Breast Cancer: 4-Year Outcomes From the NATALEE Randomized Clinical Trial.<h4>Importance</h4>Ribociclib plus a nonsteroidal aromatase inhibitor (NSAI) has demonstrated a statistically significant invasive disease-free survival (iDFS) benefit over NSAI alone in patients with hormone receptor-positive/ERBB2 (formerly HER2)-negative early breast cancer. Evaluating the efficacy and safety of adjuvant ribociclib beyond the planned 3-year treatment period is critical for understanding the long-term impact on recurrences.<h4>Objective</h4>To evaluate efficacy and safety of adjuvant ribociclib in an exploratory 4-year analysis of the NATALEE (New Adjuvant Trial With Ribociclib [LEE011]) randomized clinical trial, with all patients no longer receiving ribociclib treatment.<h4>Design, setting, and participants</h4>This exploratory analysis of an international, open-label,2025-01-01T00:00:00Z2025 Nov2026-07-15T06:51:54.59Z2026-06-30T03:28:50.472ZS-EPMC124648534099677310.1001/jamaoncol.2025.3700