The Immuno-oncology-Induced Cytokine Release Syndrome Patient Diary: A Content-Valid, Patient-Reported Outcome...

Cytokine release syndrome (CRS) occurs when the immune system reacts excessively to infections or certain immunotherapies, leading to a systemic inflammatory response. The clinical presentation of CRS is highly variable, ranging from mild symptoms, such as fever and fatigue, to severe, life-threatening conditions. Currently, there is no standardized method for collecting patient-reported data on CRS experiences. This study aims to develop a novel patient-reported outcome measure (PROM) to capture patients' experience with CRS.

A comprehensive, multistep evidence-generation process was employed, including several research steps: a literature review and analysis of Sanofi clinical trial adverse event data, semi-structured interviews with clinical experts, advisory board meetings with clinical trial investigators, concept elicitation interviews with patients who experienced CRS, a PROM development workshop, cognitive debriefing interviews with clinical trial investigators, and cognitive debriefing interviews with patients.

This review identified various CRS-related signs and symptoms from literature and anonymized safety data from clinical trials. Clinical experts validated the preliminary conceptual model (CM) and identified additional relevant symptoms. Patient interviews revealed further symptoms and impacts, leading to the development of the immuno-oncology (IO)-induced CRS patient diary. This PROM was refined through iterative feedback from clinical experts and patients, ensuring it effectively captures the incidence, severity, and impact of CRS symptoms.

The "IO-induced CRS patient diary" can be considered a content-valid tool for capturing and monitoring the most important patient-reportable symptoms and impacts of CRS in IO clinical trials. This PROM can provide a standardized understanding of IO-induced CRS from the patient perspective, where to date this has been mainly clinically assessed using diverse assessments.