Randomized Controlled Pilot Trial of a Low-Touch Remotely-Delivered Values Intervention to Promote Adherence to Adjuvant Endocrine Therapy Among Breast Cancer Survivors

Background Oral anti-cancer treatments such as adjuvant endocrine therapies (AET) for breast cancer survivors are commonly used but adherence is a challenge. Few low-touch, scalable interventions exist to increase ET adherence. Purpose To evaluate the acceptability, feasibility, and initial efficacy of a low-touch, remotely-delivered values plus AET education intervention (REACH) to promote AET adherence. Methods A mixed-methods trial randomized 88 breast cancer survivors 1:1 to REACH or Education alone. Wisepill real-time electronic adherence monitoring tracked monthly AET adherence during a 1-month baseline through 6-month follow-up (FU) (primary outcome). Patient-reported outcomes were evaluated through 3- and 6-month FU (secondary). Multiple indices of intervention feasibility and acceptability were evaluated. Qualitative exit interviews (n = 38) further assessed participants' perceptions of feasibility/acceptability and recommendations for intervention adaptation. Results The trial showed strong feasibility and acceptability, with an eligible-to-enrolled rate of 85%, 100% completion of the main intervention sessions, and "good" intervention satisfaction ratings on average. For Wisepill-assessed AET adherence, REACH outperformed Education for Month 1 of FU (p = .027) and not thereafter. Participants in REACH maintained high adherence until Month 4 of FU, whereas in Education, adherence declined significantly in Month 1. Conditions did not differ in self-reported adherence, positive affective attitudes, future intentions, or necessity beliefs. REACH trended toward less negative AET attitudes than Education at 3-month FU (p = .057) reflecting improvement in REACH (p = .004) but not Education (p = .809). Exploratory moderator analyses showed that average to highly positive baseline AET affective attitudes and oncologist-patient communication each predicted higher adherence following REACH than Education; low levels did not. Participants identified recommendations to strengthen the interventions. Conclusions REACH, a low-touch values intervention, showed good feasibility and acceptability, and initial promise in improving objectively-assessed AET adherence among breast cancer survivors (relative to education alone). Future research should target improving REACH's tailoring and endurance.