Following the granting of a marketing authorisation, including for an authorisation granted before 21 July 2012, the Director General of the Agence nationale de sécurité du médicament et des produits de santé may, by reasoned decision notified in writing, where he has concerns about the risks associated with the authorised medicinal product or product, require the holder of this authorisation to implement a risk management system, together with a detailed description of this system, within a period which he shall determine. This decision may only be taken after the holder has been invited to submit its observations within a period of thirty days. Depending on the written observations provided by the marketing authorisation holder, the Agence nationale de sécurité du médicament et des produits de santé either withdraws or confirms the obligation. If it confirms the obligation, the marketing authorisation is amended to include the measures to be taken as part of the risk management system as conditions of the marketing authorisation, in accordance with 1° of Article R. 5121-36-1.