[Problem] To provide a pharmaceutical composition for treating various cancers in which mitochondrial complex I is involved, in particular, colon cancer, leukemia and/or malignant lymphoma. [Solution] With the intention of creating pharmaceutical compositions for treating various cancers, the inventors confirmed, on the basis of the result of intensive investigation, that pharmaceutical compositions, which contain specific bicyclic nitrogen-containing aromatic heterocyclic amide compounds having an AMPK activation effect and mitochondrial complex I inhibition effect as active ingredients, have a therapeutic effect on various cancers in which mitochondrial complex I is involved, in particular, colon cancer, leukemia and/or malignant lymphoma, thereby completing the present invention.
