Cohorts as Catalysts: Stakeholder Perspectives on Strengthening EU Pandemic Preparedness Through Cohort-Trial Synergies - Dataset

The CoMeCT (Coordination Mechanism for Cohorts and Trials) project aims to strengthen the harmonisation and integration of cohort studies and clinical trials (CTs) to improve research responses to (re)emerging infectious diseases. To understand how real-world cohort data had supported the design and conduct of CTs in practice, we conducted an online, cross-sectional survey of cohort and clinical trial consortia that participate in the CoMeCT Trials Coordination Board or Cohort Coordination Board, yielding 18 responses. Respondents described facilitators for reusing participant-level cohort data, such as aligned recruitment methods, standardised biobanking logistics, and strong inter-institutional collaboration, alongside significant barriers, including regulatory and administrative constraints, unclear data standards, insufficient harmonisation methods, and tight deadlines. Cohort studies were considered essential for pandemic preparedness and response, providing real-world evidence at times when CTs were infeasible or unethical, supporting rapid epidemiological characterisation, enabling timely data and sample collection, and underpinning long-term follow-up. Examples from COVID-19 and Mpox included rapid diagnostic development and validation, identification of biomarkers of infection response, and evaluation of treatment safety and effectiveness. Respondents recommended that European funders prioritise sustained cohort funding, maintain active infrastructure between pandemics, and develop harmonised regulatory frameworks to facilitate efficient study conduct and data sharing. Strengths of EU investments included timely funding and support for data sharing, while weaknesses included fragmented funding, administrative burden, limited harmonisation, and inflexibility during emerging crises. To address these challenges, CoMeCT has developed a Cohort and Trial Metadata Repository to provide a comprehensive, living map of European cohorts, enhance data discoverability and interoperability, and strengthen Europe’s readiness for future public health emergencies.