ABSTRACT
OBJECTIVE: Non-adherence to adjuvant endocrine therapy (AET) in women with breast cancer is common and associated with medication side-effects and distress. We co-designed an Acceptance and Commitment Therapy intervention (ACTION) to enhance medication decision-making and quality of life (QoL). We undertook a pilot trial of ACTION to inform the feasibility of a phase III trial, and to examine intervention acceptability. METHODS: This was a multi-site, exploratory, two-arm, individually randomised external pilot trial. Women with early breast cancer prescribed AET were randomised (1:1) to receive usual care (UC) or UC + ACTION. The ACTION intervention comprised a remotely delivered one-to-one ACT session followed by three group sessions delivered by clinical psychologists, alongside a website containing ideas for the self-management of side effects. RESULTS: Of the 480 women screened for eligibility, 260 (54.2%) were approached and 79 (30.4%) randomised. 71 (89.9%) women provided data at 3-month and 70 (88.6%) at 6-month 40 women were randomised to receive UC + ACTION and 32 (80.0%) completed the intervention. Most (75.0%) accessed the website at least once. ACTION was acceptable to participants (Borkovec & Nau Scale: mean = 7.8 [SD = 2.7] out of 10). Signals of effectiveness in favour of the UC + ACTION arm were observed for medication adherence (Adherence Starts with Knowledge questionnaire-12), QoL (work and social adjustment scale), health-related QoL (functional assessment of cancer therapy[FACT] general and FACT-ES-19/23), distress (generalised anxiety disorder -7, patient health questionnaire-9) and psychological flexibility (valuing questionnaire). CONCLUSIONS: The ACTION intervention was acceptable to patients. There were promising signals for effectiveness on primary and secondary outcomes. A phase III randomised controlled trial is feasible. TRIAL REGISTRATION: ISRCTN12027752.