Phase II Study of Antineoplastons A10 and AS2-1 Capsules in Patients With Adenocarcinoma of the Colon

DISEASE CHARACTERISTICS: Histologically confirmed adenocarcinoma of the colon that is unlikely to respond to existing therapy and for which no curative therapy exists Measurable disease by MRI or CT scan Metastatic or unresectable disease PATIENT CHARACTERISTICS: Age: 18 and over Performance status: Karnofsky 60-100% Life expectancy: At least 2 months Hematopoietic: WBC at least 2,000/mm^3 Platelet count at least 50,000/mm^3 Hepatic: Bilirubin no greater than 2.5 mg/dL SGOT/SGPT no greater than 5 times upper limit of normal No hepatic failure Renal: Creatinine no greater than 2.5 mg/dL No renal failure Cardiovascular: No chronic heart failure No uncontrolled hypertension Pulmonary: No serious lung disease, such as chronic obstructive pulmonary disease Other: Not pregnant or nursing Fertile patients must use effective contraception during and for 4 weeks after study participation No active infection No serious malabsorption syndromes No other serious concurrent disease PRIOR CONCURRENT THERAPY: Biologic therapy: At least 4 weeks since prior immunotherapy and recovered Chemotherapy: At least 4 weeks since prior chemotherapy (6 weeks for nitrosoureas) and recovered Endocrine therapy: Concurrent corticosteroids allowed Radiotherapy: At least 8 weeks since prior radiotherapy and recovered (patients with multiple tumors may be admitted earlier) Surgery: No prior extensive stomach or intestinal surgery Other: Prior cytodifferentiating agent allowed No prior antineoplaston therapy No other concurrent anticancer therapy