A pharmaceutical combination comprising (a) an Hsp90 inhibitor that is 5- (2,4-dihydroxy-5-isopropyl-phenyl) -4- (4-morpholin-4-ylmethyl-phenyl) -isoxazol-3 acid ethylamide -carboxylic, or a pharmaceutically acceptable salt thereof and (b) a mTOR inhibitor that is rapamycin, CCI-779, ABT578 or AP23573, or a derivative thereof according to formula I '** Formula ** wherein: R1 is CH3 or alkynyl of 3 to 6 carbon atoms, R2 is H or -CH2-CH2-OH, 3-hydroxy-2- (hydroxy-methyl) -2-methyl-propanoyl or tetrazolyl, and X is>； = O , (H, H) or (H, OH), with the proviso that R2 is different from H when X is>； = O, and R1 is CH3 when R2 is -CH2-CH2-OH.Una combinación farmacéutica que comprende (a) un inhibidor de Hsp90 que es etilamida del ácido 5-(2,4- dihidroxi-5-isopropil-fenil)-4-(4-morfolin-4-ilmetil-fenil)-isoxazol-3-carboxílico, o una sal farmacéuticamente aceptable del mismo y (b) un inhibidor de mTOR que es rapamicina, CCI-779, ABT578 o AP23573, o un derivado del mismo de acuerdo con la fórmula I'**Fórmula** en donde: R1 es CH3 o alquinilo de 3 a 6 átomos de carbono, R2 es H o -CH2-CH2-OH, 3-hidroxi-2-(hidroxi-metil)-2-metil-propanoílo o tetrazolilo, y X es >；=O, (H,H) o (H,OH), con la condición de que R2 es diferente de H cuando X es >；=O, y R1 es CH3 cuando R2 es -CH2-CH2-OH.
