Abstract
PURPOSE: Adding CDK4/6 inhibitors (CDK4/6is) to endocrine therapy (ET) for HR+/HER2- early breast cancer (EBC) demonstrated statistically significant invasive disease-free survival (iDFS) benefits in monarchE (node positive, high risk, stage II/III) and NATALEE (select N0 and all macroscopic N1, stage II/III). This study evaluated patient preferences for EBC treatment attributes and how these may translate for CDK4/6i selection. METHODS: A web-based discrete choice experiment survey was conducted among US-based adult women with self-reported stage II/III HR+/HER2- EBC. Eight attributes were included, informed by 14 qualitative interviews (to identify most relevant attributes), expert clinical input, and differentiating features between CDK4/6is: efficacy (5-year iDFS), adverse events (venous thromboembolic event [VTE], diarrhea, fatigue), number of blood tests, number of electrocardiograms (EKGs), treatment duration, and schedule. Participants selected scenarios that best reflected their preferences from 10 choice cards, each displaying a pair of hypothetical treatment profiles. A conditional logit regression model was used to estimate preference weights and relative importance (RI) of attributes. RESULTS: A total of 409 women participated. Patient preferences, from high to low RI, were higher efficacy, lower diarrhea risk, lower fatigue risk, shorter treatment duration, and lower VTE risk. Number of blood tests, number of EKGs, and treatment schedule were less important. Utility scores were higher for reconstructed treatment profiles that resembled ribociclib. CONCLUSION: This study demonstrated that patients prefer adjuvant treatment with higher efficacy and lower risk of adverse events. These data will aid shared decision-making when discussing the addition of CDK4/6is to adjuvant ET for eligible patients with HR+/HER2- EBC.