Feasibility of a Smart Label-Enabled Remote Therapeutic Monitoring Intervention to Support Cyclin-Dependent Kinase 4/6 Inhibitor Adherence in Breast Cancer Care.

Abstract

Cyclin-dependent kinase 4 and 6 inhibitors (CDKIs) are effective breast cancer therapies but pose adherence challenges because of cost, side effects, and complexity of medication schedule. We assessed the feasibility and usability of a smart label-enabled remote therapeutic monitoring (RTM) mHealth intervention for women with breast cancer prescribed a CDKI. Exploratory adjusted analyses examined factors associated with usability and CDKI adherence. Participants were recruited from a comprehensive cancer center between April and August 2024. For 3 months, participants used Tappt smart labels and web app to record CDKI doses, receive missed dose reminders, report symptoms biweekly, and complete baseline and follow-up surveys. Alerts were sent to oncology teams for nonadherence (>20% missed doses) or moderate-to-severe symptoms. Feasibility was defined as ≥70% of participants using the smart label >30 days and completing the follow-up survey. Usability was assessed using the System Usability Scale, with a benchmark score of ≥68. Linear regression was used to examine factors associated with usability and CDKI adherence. Among 168 screened, 107 were eligible and reached; 75.7% (81/107) consented; 90.1% (73/81) completed the follow-up survey, and 88.9% (72/81) used the intervention >30 days. Most participants self-identified as White (69.9%), were privately insured (72.6%), and had early-stage breast cancer (58.9%) and depression or anxiety (58.9%). The mean usability score was 75.8; participants who self-identified as Black reported 12.0 points higher usability than those who self-identified as White (<i>P</i> = .03). Mean CDKI adherence was 92.8%. A history of anxiety or depression was associated with an 8.6 percentage-point lower CDKI adherence rate (<i>P</i> = .02). A smart label-enabled RTM mHealth intervention exceeded feasibility and usability benchmarks and showed promise for supporting CDKI adherence and symptom management.