This is a Phase I, multi-center study of a carbohydrate (DAVANAT) which has been shown to increase the anti-tumor activity of 5-fluorouracil in mice. 5-Fluorouracil is a chemotherapy drug commonly used in cancer patients. Patients with different type of solid tumors who have failed standard, approved treatments can be enrolled in the study. Different doses of DAVANAT will be given alone in Cycle 1, and in combination with 5-fluorouracil in cycle 2. Patients will be on study for approximately 90 days. The main reason for doing the study is to determine the safety of the drug given alone and in combination. In patients who have cancer that can be measured by CT scan, it will be determined whether the tumors change in size (get bigger, smaller or stay the same)after Cycle 2.

• Colorectal Cancer
• Lung Cancer
• Breast Cancer
• Head and Neck Cancer
• Prostate Cancer

• Drug: DAVANAT
• Drug: 5-fluorouracil

Inclusion Criteria

• The subject is able to give informed consent to participate in this trial (including all procedures and follow-up visits).
• The subject is male or female at least 18 years of age.
• The subject has a documented histologic or cytologic recurrent or metastatic solid tumor that is not amenable to curative surgery, radiotherapy, or conventional chemotherapy of proven value.
• Subjects must have completed previous therapy (chemotherapeutic agents or other therapies including radiation) at least 4 weeks prior to study entry.
• Following major surgery (e.g. laparotomy), > 4 weeks must have elapsed and subjects must have recovered from effects.
• Following minor surgery (does not include insertion of vascular access device), > 2 weeks must have elapsed.
• ECOG performance status of 0-2.
• The subject has a life expectancy of at least 12 weeks.
• Female subjects must be post-menopausal, surgically sterile, or using effective contraception.

Laboratory values prior to administration of study drug:

• If female and not post-menopausal, the subject has a negative pregnancy test.
• Liver function studies: AST and ALT < 2.5 times the upper limit of normal (ULN); total bilirubin < 1.5
• Hematopoietic parameters: WBC > 3000 per mm3; Granulocyte count > 1,500 per mm3; Platelet count > 100,000 per mm3
• Renal: Creatinine < or = ULN
• Pulmonary: Dlco > or = 60% of predicted

Exclusion Criteria

• If female, the subject is pregnant or breast feeding.
• Central nervous system (CNS) metastases or primary CNS tumors.
• The subject has a known hypersensitivity to DAVANAT™ or any of its components.
• The subject has congestive heart failure or any other medical condition that could be adversely affected by intravenous infusion of up to approximately 200 mL of fluid over 60 minutes.
• The subject is currently abusing alcohol and/or illicit drugs.
• The subject has other significant medical, psychiatric, or social conditions which, in the investigators’ opinion, may compromise the subject's safety in participating in this study.
• In the investigators’ judgment, the subject would be unreliable in adhering to the study visit schedule or other study requirements.
• The subject is currently enrolled in a clinical trial or has participated in a clinical trial within the 30 days prior to entry into this study.