[Problem] Provided is a pharmaceutical composition for treating lung cancer in which mitochondrial Complex I is involved, particularly non-small cell lung cancer.[Means for Solution] The inventors of the present invention conducted examinations on a compound having an effect of inhibiting mitochondrial Complex I, and confirmed that a bicyclic nitrogen-containing aromatic heterocyclic amide compound of the present invention has the effect of inhibiting mitochondrial Complex I and that this compound exhibits an anti-tumor effect on mice bearing tumors of non-small cell lung cancer-derived cells, and therefore completed the present invention.
