The AtOM CF Study - How can Adherence to Oral Medication be improved for the benefit of people with cystic fibrosis.

Background Cystic Fibrosis (CF) is an inherited, chronic, multisystem disease caused by mutations in the CF Transmembrane conductance regulator (CFTR) gene1.

CFTR modulator medicines are a novel, expensive treatment for CF that correct the baseline defect in CFTR dysfunction2,3.

They have been shown to improve lung function, nutritional status and stabilisation of the disease, improving survival2-7. Despite positive health benefits adherence has been shown to be variable8.

Understanding the reason for non-adherence is vital in assisting with intervention design to optimise the health benefits of this new treatment. Optimisation is essential as treatment costs approximately £110,000 per patient per annum9. Research Question. The AtOM CF Study - How can Adherence to Oral Medication be improved for the benefit of people with Cystic Fibrosis?

Aim To develop a patient-centred complex intervention to enhance and optimise adherence to oral medication with a focus on CFTR modulators in the person with cystic fibrosis (PwCF).

Objectives: To synthesise existing literature on adherence to oral medication, including CFTR modulators in PwCF, and characterise the impact of interventions tested to improve adherence.

To determine adherence to CFTR modulators and assess the burden of prescribed medication in adults attending two adult CF centres in England.

To explore the perceptions and experiences of CFTR modulator therapy in PwCF including in relation to health status, adherence and necessity of other routinely prescribed CF medications.

Co-design an intervention using a modified Experience Based Co-Design approach to support long-term adherence to oral medication with a focus on the CFTR modulators in PwCF.

Methods and timeline Work package 1 (month 1-8): Mixed methods systematic review focusing on adherence to oral medication, in the PwCF and assessment of the impact of interventions to improve adherence.

Work package 2 (month 7-11) : Medicines possession ratio (MPR) will be utilised to calculate adherence rates of the CFTR modulators in the target population. The burden of prescribed medication will be quantified utilising the Living with Medicines Questionnaire version 3.

Work package 3 (month 11-25): Semi-structured Interviews, utilising photo elicitation in two adult CF centres, to provide a conceptual framework for work package 4.

Work package 4 (month 23-30): PwCF and staff will co-design an intervention to optimise adherence to oral medication in CF. The last six months will be dedicated to write up and dissemination.

Impact and dissemination Research findings will be published in international peer-reviewed journals and presented at regional, national and international conferences.

They will be shared with patients and public through social media, written summaries such as a patient newsletter and oral presentations, co-authored with PPI. Photographs obtained during work package 3 of the research will displayed in an exhibition and through social media. The intervention will be based on theory and co-designed utilising the patient's perspective.

Following the MRC Framework for design and evaluation of complex interventions10, it is anticipated that there will be a feasibility post-doctoral study, providing the basis for a definitive trial in order to provide rigorous evidence regarding the impact of the intervention on adherence and patient outcomes.