Task 6.4: Engaging with regulators on the use of new evidence in decision making To demonstrate the ability of the ecosystem and ConcePTION pipeline to generate useful information in a timely fashion on safety of medications in pregnancy and breastfeeding work was completed across several work packages. Work packages 1-4 were engaged in addressing generation of evidence from different underlying data sources. Work package 7 enabled the rapid generation of high-quality evidence from WP1 & 2 by providing governance rules, ethical standards and an IT infrastructure for data harmonization, sharing of data and data characterization. In addition, throughout the lifetime of ConcePTION project WP6 members conducted examinations with each of the scientific work packages to assess the potential relevance of their work to regulatory decisionmakers. A series of demonstration studies have been conducted in WP1 (population-based data sources), WP2 (reported pregnancies by women and their HCP), WP3 (develop, characterize, validate and apply a nonclinical testing platform for reliable prediction of medicine concentrations in human breast milk along with systemic exposure of breastfed infants to maternal medicines) and WP4 (breast milk transfer preclinical and in silico modelling, and human milk biobank sampling with drug concentration studies). The choice of the specific studies is based on pre-defined criteria, such as demonstration of the ability to detect associations between medication use and a range of birth/child outcomes (WP1 & 2), testing a range of medications with differing physico-chemical properties, e.g., including lipophilic, hydrophilic and biologicals (WP3 & WP 4), clinical relevance (aligned with stakeholder priorities and needs; WP6) and quality assessment of case identification algorithms (WP7). Examples range from simple drug utilization/ event rates to the complexity of associations studies on long-term neurodevelopmental outcomes of antidepressant use during pregnancy. The scientific use cases will test and illustrate the ConcePTION ecosystem: data, methods, collaboration, governance, and analytical tools for the entire range of users