# A community pharmacy-based program to enhance adherence to adjuvant endocrine therapy among breast cancer survivors (PACHA): protocol for a pilot cluster-randomized controlled trial

## TL;DR

This study tests a pharmacy-based program to help breast cancer survivors adhere to their long-term hormone therapy, using pharmacist support and online resources.

## Contribution

The novel contribution is a community pharmacy-led intervention using motivational interviewing and online tools to improve adherence to adjuvant endocrine therapy.

## Key findings

- The PACHA program will be tested for acceptability and feasibility in a pilot cluster-randomized controlled trial.
- Results will inform the design of a full-scale trial to assess the program's impact on adherence and costs.
- Pharmacist-led interventions using training and online resources may improve breast cancer survivorship outcomes.

## Abstract

Adjuvant endocrine therapy (AET) is an oral treatment prescribed for 5 to 10 years to women with hormone-sensitive breast cancer. Despite the benefits of AET for reducing breast cancer recurrence, suboptimal adherence is common. Community pharmacists can play a role in supporting women with this treatment, given their frequent encounters with patients, access to refill information, and expertise in managing side effects. The goal of this pilot study is to assess the acceptability and feasibility of implementation, and preliminary effects of the PACHA program, a community pharmacy-based program designed to support women who are prescribed AET. Another goal is to assess the feasibility of a large-scale randomized controlled trial (RCT).

This is a pilot cluster-RCT using mixed-methods. A cluster consists of a pharmacy, its pharmacists, and its patients with an AET prescription in the last 30 months. Pharmacies will be recruited through targeted advertisement. Participating pharmacies will be randomized 1:1 to two groups (n = 33 pharmacies per group). In the first group (control), pharmacists will provide usual services to women. In the second group (intervention), pharmacists will complete web-based training and perform consultations using a standardized guide based on motivational interviewing principles and evidence-based online strategy sheets to cope with AET side effects. Women in the intervention group will have access to a website featuring video modules on AET, strategies for managing side effects, testimonials from women who have had an AET, and a list of resources. Acceptability and feasibility indicators, as well as psychosocial factors expected to influence AET adherence and treatment experience, will be collected at baseline, during, and at the end of the 6-month follow-up using online questionnaires, study data logs, and pharmacy claim records. Semi-structured interviews will be conducted to explore participants’ experiences with the program.

Results will help to refine the program and, if the results support this, to design a full-scale cluster-RCT to assess the program’s effect on 5-year adherence and costs. If effective, this program could fill a gap in breast cancer supportive care and contribute to reducing cancer burden by improving survivorship experience and survival.

This trial has been approved by the Research Ethics Board of the CHU de Québec-Université Laval (MP-20–2023-6625) and registered at Clinicaltrials.gov (NCT05887102) on 2023–05-24, https://classic.clinicaltrials.gov/ct2/show/NCT05887102, prior to beginning the study. Protocol version 1 is dated as 2022–12-12.