 This is a Phase I, open-label study of escalating dose levels of 1018 ISS in combination with irinotecan and cetuximab in patients with previously treated metastatic colorectal cancer. Approximately 15 patients will be treated. The objectives of this study are to establish a safe, tolerable, and active dose of 1018 ISS, determine tumor response, time to disease progression, and overall survival in treated patients. 