This publication presents the data and findings of the risk assessment on methyl 3,3-dimethyl-2-{[1-(pent-4-en-1-yl)-1H-indazole-3-carbonyl]amino}butanoate (MDMB-4en-PINACA), carried out by the extended Scientific Committee of the EMCDDA on 9 December 2020. On the basis of the Risk Assessment Report, on 12 March 2021, the Commission decided that MDMB-4en-PINACA should be included in the definition of 'drug', in the Annex to Framework Decision 2004/757/JHA.