A crystalline form of (S)-1-(4-Chloro-phenyl)-7-isopropoxy-6-methoxy-2-(4-{methyl-[4-(4- methyl-3-oxo-piperazin-1-yl)-trans-cyclohexylmethyl]-amino}-phenyl)-1,4dihydro-2H- isoquinolin-3-one, which is useful in the treatment of a disease or disorder associated with the interaction between p53, or variants thereof, and MDM2 and/or MDM4, or variants thereof, respectively, (I).Linvention concerne une forme cristalline de (S)-1-(4-Chloro-phenyl)-7-isopropoxy-6-methoxy-2-(4-{methyl-[4-(4- methyl-3-oxo-piperazin-1-yl)-trans-cyclohexylmethyl]-amino}-phenyl)-1,4-dihydro-2H- isoquinolin-3-one utilisée pour traiter une maladie ou un trouble associé à linteraction respective entre p53, ou ses variants, et MDM2 et/ou MDM4, ou leurs variants, respectivement, (I)
