The present invention relates to a novel class of quinolone-4-carboxamide Pf3D7 inhibitors of general formula (I) (Formula (I)) wherein R1, R2, R3, R4, R5, R6, R7, R8 and X are as defined herein, to their use in medicine, and in the treatment of malaria in particular, to compositions containing them, to processes for their preparation and to intermediates used in such processes.