"I just wanted to speak to someone- and there was no one…": using Burden of Treatment Theory to understand the impact of a novel ATMP on early recipients.

Background: Advanced therapy medicinal products such as Chimeric antigen receptor T-cell therapy offer ground-breaking opportunities for the treatment of various cancers, inherited diseases, and chronic conditions. With development of these novel therapies continuing to increase it's important to learn from the experiences of patients who were among the first recipients of ATMPs. In this way we can improve the clinical and psychosocial support offered to early patient recipients in the future to support the successful completion of treatments and trials.

Study Design: We conducted a qualitative investigation informed by the principles of the key informant technique to capture the experience of some of the first patients to experience CAR-T therapy in the UK. A directed content analysis was used to populate a theoretical framework informed by Burden of Treatment Theory to determine the lessons that can be learnt in supporting their care, support, and ongoing self-management.

Results: A total of five key informants were interviewed. Their experiences were described within the three domains of the burden of treatment framework; (1) The health care tasks delegated to patients, Participants described the frequency of follow-up and the resources involved, the esoteric nature of the information provided by clinicians; (2) Exacerbating factors of the treatment, which notably included the lack of understanding of the clinical impacts of the treatment in the broader health service, and the lack of a peer network to support patient understanding; (3) Consequences of the treatment, in which they described the anxiety induced by the process surrounding their selection for treatment, and the feeling of loneliness and isolation at being amongst the very first recipients.

Conclusions: If ATMPs are to be successfully introduced at the rates forecast, then it is important that the burden placed on early recipients is minimised. We have discovered how they can feel emotionally isolated, clinically vulnerable, and structurally unsupported by a disparate and pressured health service. We recommend that where possible, structured peer support be put in place alongside signposting to additional information that includes the planned pattern of follow-up, and the management of discharged patients would ideally accommodate individual circumstances and preferences to minimize the burden of treatment.