Abstract
BACKGROUND: Cyclin-dependent kinase 4/6 inhibitors (CDKIs) improves survival when added to endocrine therapy in hormone receptor-positive (HR+), human epidermal growth factor receptor 2-negative (HER2-) breast cancer. However, their complex schedule, side effects, and cost contribute to non-adherence. METHODS: The EAQ221CD is a two-arm randomized controlled trial that evaluates the effectiveness of the CONnected CUstomized Treatment Platform (CONCURxP), a mobile health intervention, versus enhanced usual care (EUC) on CDKI adherence among 390 patients with breast cancer and a new CDKI prescription. Participants use a smart pouch (Wisebag) to monitor real-time adherence. CONCURxP arm patients: (1) receive text reminders for missed or extra doses; (2) receive text message surveys inquiring reasons for missed or extra doses; and (3) have access to their adherence history on a study web portal. Missed or double doses trigger alerts to the oncology team. Patients citing cost as a barrier are referred to a national non-profit financial navigation program. EUC arm patients receive educational materials on side effect management. Patients complete surveys at baseline, 3, 6, and 12 months after randomization. Our objectives are to: (1) compare 12-month CDKI adherence measured using Wisebag (primary outcome) between the two arms; (2) compare patient-reported outcomes at 12-months between the two arms, including symptom burden, quality of life, patient-provider communication, self-efficacy for managing symptoms, and financial worry; and (3) use mixed methods to describe patients' experience with the CONCURxP intervention. Our multilevel intervention will provide actionable results to improve adherence, health outcomes, and patients' experience. TRIAL REGISTRATION: NCT06112613.