The Diarrhea Prevention with an investigational drug trial, will evaluate whether adding an investigational drug to the standard treatment for advanced colorectal cancer can reduce the amount of diarrhea a patient experiences. The standard and approved treatment for patients with metastatic colorectal cancer is repeated cycles of chemotherapy consisting of a combination of irinotecan (also known as CPT-11, Camptosar), 5-fluorouracil (also known as 5FU), and leucovorin (also known as LV). Preclinical data from animal models suggest that the investigational drug may offer an effective means for preventing CPT-11/5FU/LV-induced diarrhea. It is also hypothesized that the investigational drug-mediated anti-angiogenesis could induce a favorable tumor response.