ATB-346 is anti- inflammatory agent, which is structurally an analogue of naproxen. ABT-346 exhibits anti-inflammatory properties similar to naproxen, but with substantially reduced gastrointestinal toxicity. ATB-346 suppressed colonic prostaglandin synthesis and whole blood thromboxane synthesis as effectively as naproxen, but did not induce any gastrointestinal injury. ATB-346 exerts superior chemopreventive effects to those of naproxen, while sparing the gastrointestinal tract of the injury normally associated with use of the parent drug. ATB-346 may therefore be an attractive agent for chemoprevention of colon cancer, and possibly of cancers in other tissues.