Background Patient-centred trials address patient relevant questions, have protocols that maximise recruitment and retention, as well as effective communication strategies. Involving patients and carers in trial design and oversight is essential for patient-centred research. In the Edmond J Safra ACT-PD ini- tiative we are developing the first multi-arm multi-stage (MAMS) trial for disease modifying Parkinson’s treatments. Here we present our patient-centred approach.

Methods Seven people with Parkinson’s (PwP) and three care partners (CP) (3 male, 7 female) were recruited nationally and two allocated to each of 5 working groups (WG) developing the trial. Together they form a Patient and Public Involvement and Engagement (PPIE) WG chaired by PwP (KMcF). The group iteratively developed processes for supporting their input into WG decisions with an impact evalu- ation plan involving semi-structured interviews and a revised Patient Engagement in Research Scale).

Results The PPIE team meets every six weeks online. Standard Reporting Forms facilitate communication between WGs and PPIE members, supporting group input into issues arising. PPIE feedback is an agenda item at all WG meetings. Post-WG PPIE debriefs with the WG chairs ensure a shared understanding of discussions. Monthly PPIE forums provide opportunity for informal education and themed discussions with PwP/CP. A PwP/CP WhatsApp group creates a safe space for sharing experiences and ideas.

Conclusion We have developed a process by which PwP/CP can meaningfully co-design our MAMS trial, ensuring it is truly patient-centred.