The development of medicine, biomicrobiology and biotechnology has led to the emergence of a cutting-edge category of medicinal products that use gene therapy, somatic cell therapy and engineered tissues for preventing, treating or even curing human diseases. The Novelty, complexity and diversity of such products has demanded new regulatory tools, both in terms of legislation and regulatory guidance, to allow an appropriate balancing of the risks and the benefits for the patients. EU and UK legislature regulates this category of products as ‘advanced therapy medicinal products (ATMPs)’ in order to ensure the highest level of protection of public health and to take into account their specific challenges, in particular with regard to clinical trials, manufacturing and Pharmacovigilance. However, the regulation of genetically modified organisms (GMOs) which are used as starting materials for ATMPs remains national and therefore differs from one Member State to another. Such differences have led to a complex regulatory landscape for ATMPs. The regulation of tissues and cells is also currently being