Irinotecan Hydrochloride with or without Chinese Herbal Formulation PHY906 in Treating Patients with Metastatic Colorectal Cancer

Inclusion Criteria

• Patients with histologically confirmed metastatic colorectal cancer, who have received and/or progressed on a prior oxaliplatin-based chemotherapy regimen
• Patients must have been off of chemotherapy for at least 4 weeks prior to day 1 of cycle 1; informed consent can be signed at any time prior to the start of therapy
• Patients with wild-type or mutant Kirsten rat sarcoma 2 viral oncogene homolog (KRAS) metastatic colorectal cancer (mCRC)
• At least one measurable lesion by Response Evaluation Criteria In Solid Tumors (RECIST) 1.1
• Eastern Cooperative Oncology Group (ECOG) performance status 0-2
• Expected survival of at least 6 months
• Women of child-bearing potential (i.e., women who are pre-menopausal or not surgically sterile) must use acceptable contraceptive methods (abstinence, intrauterine device [IUD], oral contraceptive or double barrier device), and must have a negative serum or urine pregnancy test within 1 week prior to beginning treatment on this trial; nursing patients are excluded; sexually active men must also use acceptable contraceptive methods
• Must be able and willing to give written informed consent
• Absolute neutrophil count (ANC) >= 1,500/ mm^3
• Platelets >= 100,000/ mm^3
• Hemoglobin >= 9 gm/dL (may be corrected by transfusion)
• Bilirubin < 1.5 x upper limit of normal (ULN)
• Aspartate aminotransferase (AST) =< 2.5 x ULN or alanine aminotransferase (ALT) =< 2.5 x ULN (Note, if both AST and ALT are done, both must be =< 2.5 x ULN) OR
• AST =< 5.0 x ULN or ALT =< 5.0 x ULN is acceptable if liver has tumor involvement; (Note, if both AST and ALT are done, both must be =< 5.0 x ULN)
• Serum creatinine =< 2 x ULN
• Serum potassium within institutional limits of normal (may be corrected with potassium repletion)
• All subjects must be capable of swallowing multiple capsules

Exclusion Criteria

• Continued treatment with bevacizumab with documented evidence of disease progression on a bevacizumab-containing regimen
• Uncontrolled or symptomatic brain metastasis
• Serious concomitant systemic disorders (e.g., active infection) that, in the opinion of the investigator, would compromise the safety of the patient or compromise the patient’s ability to complete the study
• Unwilling or unable to follow protocol requirements or to give informed consent
• Treatment with cytotoxic or biologic agents within the 4 weeks prior to beginning treatment on this study (6 weeks for mitomycin or nitrosoureas); at least 4 weeks must have elapsed from any prior surgery, radiation, hormonal or other drug therapy for their cancer
• Known human immunodeficiency virus (HIV) positivity
• Presence of metastatic disease that, in the opinion of investigators, would require palliative treatment within 4 weeks of enrollment
• Altered mental status precluding understanding of the informed consent process and/or completion of the necessary studies
• Pregnant or breast-feeding women
• Men and women of childbearing age and potential, who are not willing to use effective contraception
• Major surgery within the previous 4 weeks
• Patients taking concurrent medications of any kind which are strong inducers or inhibitors of cytochrome P450 family 3, subfamily A, polypeptide 4 (CYP3A4); patients receiving any of the following will be excluded: ketoconazole, itraconazole, clarithromycin, atazanavir, indinavir, nefazodone, nelfinavir, ritonavir, saquinavir, telithromycin, voriconazole, phenytoin, carbamazepine, rifampin, rifabutin, rifapentin, phenobarbital, St. John’s wort
• Patients previously treated with irinotecan-containing regimen