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}-phe nyl)-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).Una forma cristalina de la (S)-1-(4-cloro-fenil)-7-isopropoxi-6-me toxi-2-(4-{metil-[4-(4-metil-3-oxo-piperazin-1-iI)-trans-ciclohex il-metil]-amino}-fenil)-1, 4-dihidro-2H-isoquinolin-3-ona, la cual es útil en el tratamiento de una enfermedad o de un trastorno asociado con la interacción entre p53, o variantes de la misma, y MDM2 y/o MDM4, o variantes de las mismas, respectivamente, (I).
