Background : Good Manufacturing Practice (GMP) guidelines established by the European Commission are essential to ensure quality, safety and efficacy of medicinal products. Guidelines are designed to address specific risks of medicinal products and as such, are continuously being adapted. Advanced Therapy Medicinal Products (ATMPs) are medicinal products that have been regulated in the European Union from 2007 to cover the emerging field of genes, tissues or cell-based therapies. Dedicated GMP guidelines for ATMPs are enforceable since 2017. Consequently, GMP guidelines covering manufacture of biological active substances and medicinal products for human use including biological active substances (hereafter “Biologicals”) have been revised in June 2018 with the objective to prevent overlapping scope. Research question and methods: Our hypothesis is that the biological nature that commonly characterize ATMPs and biologicals may sustain a large body of similarities in the manufacturing aspects as addressed by the respective guidelines. We aim to comparatively analyze the two following texts : Guidelines on Good Manufacturing Practice specific to Advanced Therapy Medicinal Products, and Manufacture of Biological active substances and Medicinal Products for human use including biological active substances. Focus has been given on manufacturing, i.e. production recommendations including personnel, premises, equipment, documentation, starting and raw materials, seed lot and cell bank systems. In a systematic approach we highlighted similarities and specificities in the text outlines (paragraph and section titles). Then content has been comparatively investigated based on chosen relevant key words found in both texts (production, operation principles, production area, facilities, cross contamination in production, environmental monitoring and specifications, starting and raw materials).