The present invention relates to a novel and improved method for the preparation of (4S)-4-(4-cyano-2-methoxyphenyl)-5-ethoxy-2,8-dimethyl-1,4-dihy dro-1-6-naphthyridine-3-carboxamide of the formula (I) and of a crystalline modification of said compound.La presente invención se refiere a un procedimiento nuevo y mejorado para la preparación de (4S)-4-(4-ciano-2-metoxifenilo)-5- etoxi-2,8-dimetilo-1,4-dihidro-1,6-naftiridina-3-carboxamida de la fórmula (I). (ver Fórmula).
