Inclusion Criteria

DISEASE CHARACTERISTICS: Histologically or cytologically confirmed stage IV colorectal
cancer Measurable disease defined as lesions that measure at least 20 mm in one dimension
using conventional techniques or at least 10 mm with spiral CT scan not including: Bone
lesions Leptomeningeal disease Ascites Pleural/pericardial effusion Inflammatory breast
disease Lymphangitis cutis/pulmonis Abdominal masses that are not confirmed and followed
by imaging techniques Cystic lesions Recurrent disease allowed after adjuvant chemotherapy
if recurrence occurred at least 6 months after completion of therapy No known brain
metastases

PATIENT CHARACTERISTICS: Age: 18 and over Performance status: ECOG 0-2 Karnofsky 60-100%
Life expectancy: Greater than 12 weeks Hematopoietic: WBC at least 3,000/mm3 Absolute
neutrophil count at least 1,500/mm3 Platelet count at least 100,000/mm3 Hepatic: Bilirubin
normal AST/ALT no greater than 2.5 times upper limit of normal Renal: Creatinine normal
Cardiovascular: No history of symptomatic congestive heart failure, unstable angina, or
cardiac arrhythmia (e.g., supraventricular tachycardia or atrial fibrillation) Other: Not
pregnant or nursing Negative pregnancy test Fertile patients must use effective
contraception No significant episodes of hypoglycemia in past 6 months No known allergies
to compounds of similar chemical or biologic composition to chloroquinoxaline sulfonamide
No known glucose-6 phosphate deficiency or hemolytic anemia No uncontrolled concurrent
illness (e.g., active infection) No concurrent psychiatric illness or social condition
that would preclude compliance

PRIOR CONCURRENT THERAPY: Biologic therapy: One prior biologic therapy allowed
Chemotherapy: See Disease Characteristics No more than one prior chemotherapy for
metastatic disease or adjuvant treatment At least 4 weeks since prior chemotherapy (6
weeks for nitrosoureas or mitomycin) and recovered Endocrine therapy: No concurrent oral
hypoglycemics or insulin Radiotherapy: At least 4 weeks since prior radiotherapy and
recovered Surgery: Not specified Other: No other concurrent investigational agents No
concurrent combination antiretroviral treatment for HIV