Safety Study of Recombinant NAPc2 to Prevent Tumor Progression and Metastases in Metastatic Colon Cancer

* Tissue diagnosis of adenocarcinoma of the colon or rectum * Documented metastatic disease with at least one measurable lesion by RECIST criteria * Previously treated with 5-FU-based chemotherapy in the form of FOLFIRI, FOLFOX, or XELOX plus bevacizumab as first-line chemotherapy and have recorded progressive disease during treatment or after discontinuation of treatment, when discontinuation of treatment occurred less than 6 months before enrollment (Stage I) or randomization (Stage II) * Estimated life expectancy of at least 6 months * Age 18 to 75 years * Last dose of adjuvant or radiosensitizing chemotherapy less than 6 months before enrollment * No other active malignancy for which the subject is currently receiving treatment (other than mCRC) * No ongoing therapy with or need for parenteral and oral antithrombotics including anticoagulants and anti-platelet agents (including aspirin) and thrombolytics * No contraindication to systemic anticoagulation * No contraindication to modified FOLFOX6 or FOLFIRI combination chemotherapy * No receipt of any investigational compound within 28 days of enrollment