Azacitidine and CAPOX in Metastatic Colorectal Cancer

Inclusion Criteria:

1. Phase I: Patient must have histologically or cytologically confirmed colorectal adenocarcinoma with metastatic disease documented on diagnostic imaging studies. Disease may be measurable or non-measurable as per RECIST version 1.1.
2. ECOG performance status 0-2
3. For patients on full-dose low-molecular weight anticoagulation, no active bleeding or pathological condition that carries a high risk of bleeding (e.g., tumor involving major vessels or know varices) is allowed.
4. Serum bilirubin levels </= 1.5 times the upper limit of the normal range for the laboratory (ULN)
5. Serum aspartate aminotransferase (AST) or serum alanine aminotransferase (ALT) levels </= 2.5 x ULN and </= 5 x ULN in patients with liver metastases
6. Serum creatinine levels </= 1.5 x ULN
7. Absolute neutrophil count of >/=1,500/mm^3 (ie, >/=1.5 x 10^9/L by International Units [IU]).
8. Platelet count >/=100,000/mm^3 (IU: ≥100 x 10^9/L).
9. Hemoglobin value of >/=9.0 g/dL.
10. No limit to number of prior therapies.
11. Women of childbearing potential must have a negative serum pregnancy test and must be advised to avoid becoming pregnant. Men should be advised to not father a child while receiving treatment. Sexually active women of childbearing potential and men must use an effective method of birth control during the course of the study, in a manner such that risk of failure is minimized.
12. Patient must be refractory to treatment with 5-FU (either intravenous 5-FU or as the oral prodrug, capecitabine) and oxaliplatin, defined as previous clinical or radiographic progression on or within 3 months of treatment with 5-FU and oxaliplatin. There is no limit to the number of prior lines of therapy.
13. Phase II: Patient must have histologically or cytologically confirmed colorectal adenocarcinoma with measurable metastatic disease documented on diagnostic imaging studies by RECIST version 1.1 criteria
14. Phase II: Patient must be known to have CpG island methylator phenotype.

Exclusion Criteria:

1. Patients with known brain metastases or carcinomatous meningitis
2. Patients unable to swallow oral medications or with gastrointestinal disorders that might interfere with proper absorption of oral drugs.
3. Known dihydropyrimidine (DPD) deficiency
4. Grade 3 or more peripheral neuropathy
5. Chemotherapy or any other investigational agents within 14 days of first receipt of study treatment, or major surgery within 28 days of first receipt of study treatment, or palliative radiation within 7 days of first receipt of study treatment.
6. Concurrent severe and/or uncontrolled medical conditions which could compromise participation in the study such as unstable angina, myocardial infarction within 6 months, unstable symptomatic arrhythmia, uncontrolled diabetes, serious active or uncontrolled infection.
7. Known or suspected hypersensitivity to azacitidine or mannitol
8. Pregnant or breast feeding
9. Because of the interaction between coumadin and capecitabine patients taking therapeutic doses of coumarin-derivative anticoagulants, are not eligible. Low-dose Coumadin (e.g. 1 mg PO per day) in patients with in-dwelling venous access devices is allowed but increased frequency of INR monitoring is recommended.
10. Interstitial pneumonia or extensive and symptomatic interstitial fibrosis of the lung.