| Abstract: |
Background: Despite standard-of-care adjuvant endocrine therapy (ET) and chemotherapy, the risk of recurrence remains in patients with hormone receptor-positive/human epidermal growth factor receptor 2-negative (HR+/HER2−) early breast cancer (EBC). In phase III trials with different eligibility criteria, adjuvant ribociclib (NATALEE) and abemaciclib (monarchE) demonstrated significant invasive disease survival benefit when added to ET. We present a real-world analysis of patients with HR+/HER2− EBC that are potentially eligible for NATALEE and monarchE. Patients and methods: Data from the ConcertAI Patient360 database (January 2015-January 2023) were analyzed. The key inclusion criteria were patients ≥18 years of age with stage I-III HR+/HER2− EBC at diagnosis who had surgery and initiated adjuvant ET. NATALEE and monarchE eligibility criteria were defined per their respective trial protocols. Results: Overall, 7060 patients met the inclusion criteria, of whom 30.6% were eligible for NATALEE and 14.5% for monarchE. All patients with N2 or N3 disease were eligible for both trials. Among 1388 (19.7%) patients with N1 disease, 91.8% and 45.9% were eligible for NATALEE and monarchE, respectively. Patients with N0 disease were 74.9% of the population, of whom 9.5% were eligible for NATALEE and none for monarchE. Among the NATALEE-eligible patients with high-risk N0 disease, most were postmenopausal (72.6%) with a grade 3 tumor (61.6%); 48.9% had received prior chemotherapy. Conclusions: The results from this large real-world database study indicate that 30.6% of patients with HR+/HER2− EBC met the eligibility criteria for NATALEE versus 14.5% for monarchE, presenting the opportunity to improve outcomes in nearly one-third of patients with HR+/HER2– EBC at high risk of recurrence. © 2025 The Author(s) |
