Sparfosic acid trisodium is a DNA antimetabolite agent and a potent inhibitor of aspartate transcarbamoyl transferase.Aspartate transcarbamoyl transferase catalyzes the second step of de novo pyrimidine biosynthesis. Sparfosic acid trisodium synergistically enhances the cytotoxicity of a combination of 5-fluorouracil (5-FU) and interferon-alpha (IFN) against human colon cancer cell lines.