ANTI-TUMOR AGENT

The present application provides a method for the treatment of tumors where the lethal dose of (Z)-N-[2-methoxy-5-[2-(3,4,5-trimethoxyphenyl)vinyl]phenyl]-L-serinamide is increased to twice or more, the toxicity at the pharmaceutically effective dosage of (Z)-N-[2-methoxy-5-[2-(3,4,5-trimethoxyphenyl)vinyl]phenyl]-L-serinamide is reduced, gastrointestinal toxicity at the pharmaceutically effective dosage of (Z)-N-[2-methoxy-5-[2-(3,4,5-trimethoxyphenyl)vinyl]phenyl]-L-serinamide is reduced, hepatic toxicity at the pharmaceutically effective dosage of (Z)-N-[2-methoxy-5-[2-(3,4,5-trimethoxyphenyl)vinyl]phenyl]-L-serinamide is reduced, and/or cardiovascular toxicity at the pharmaceutically effective dosage of (Z)-N-[2-methoxy-5-[2-(3,4,5-trimethoxyphenyl)vinyl]phenyl]-L-serinamide is reduced, by administering to a subject in need thereof a composition containing: (a) an effective amount of an anti-inflammatory active substance, wherein the anti-inflammatory active substance is a Dexamethasone selected from the group consisting Dexamethasone, an ester of Dexamethasone, and a salt of Dexamethasone; and (b) (Z)-N-[2-methoxy-5-[2-(3,4,5-trimethoxyphenyl)vinyl]phenyl]-L-serinamide or a salt thereof.