AbstractBackgroundMany factors contribute to developing and conducting a successful multi‐data source, non‐interventional, post‐authorization safety study (NI‐PASS) for submission to multiple health authorities. Such studies are often large undertakings; evaluating and sharing lessons learned can provide useful insights to others considering similar studies.ObjectivesWe discuss challenges and key methodological and organizational factors that led to the delivery of a successful post‐marketing requirement (PMR)/PASS program investigating the risk of cardiovascular and cancer events among users of mirabegron, an oral medication for the treatment of overactive bladder.ResultsWe provide context and share learnings, including sections on research program collaboration, scientific transparency, organizational approach, mitigation of uncertainty around potential delays, validity of study outcomes, selection of data sources and optimizing patient numbers, choice of comparator groups and enhancing precision of estimates of associations, potential confounding and generalizability of study findings, and interpretation of results.ConclusionsThis large PMR/PASS program was a long‐term commitment from all parties and benefited from an effective coordinating center and extensive scientific interactions across research partners, scientific advisory board, study sponsor, and health authorities, and delivered useful learnings related to the design and organization of multi‐data source NI‐PASS.