KD018 is an oral form of a spray dried aqueous extract composed of four main herbs, which have been used in the Orient for nearly 2000 years for a variety of GI symptoms including diarrhea and nausea/vomiting. Extensive pre-clinical research has been done with Chinese herbal medicine, and studies have documented significant anticancer activity in combination with various cytotoxic agents including Irinotecan, which is a semi-synthetic derivative of the natural alkaloid camptothecin and belongs to the class of topoisomerase I inhibitors. The proposed plan will investigate the mechanism and efficacy of Chinese herbal medicine as an adjunct to chemotherapy in treatment of patients with metastatic colorectal cancer. Our rationale for the therapeutic use of KD018 is its potential activity in reducing chemotherapy-induced toxicity, especially diarrhea.