
    insufficient enrollment
  
['ulcerative colitis']
['tacrolimus', 'vedolizumab']

        Inclusion Criteria:

          1. Patients aged 18 to 65 years with a confirmed diagnosis of UC.

          2. Diagnosis of UC established at least 6 months before enrollment or evidence of
             chronicity in colonic biopsies.

          3. Patients with UC disease extent beyond 15 cm (must involve at least the sigmoid colon)

          4. In female patients:

               -  Post-menopausal for ≥1 year before screening, or

               -  Surgically sterile, or

               -  Agree to be on a contraceptive method from the screening visit through 4 weeks
                  after discontinuing tacrolimus (or placebo), or

               -  Completely abstain from heterosexual intercourse.

          5. In male patients:

             o Agreement not to father a child through 4 weeks after discontinuing tacrolimus
             (through contraception or abstinence).

          6. Moderate to severe UC

               -  Mayo Clinic partial UC score of 6 to 12, with a baseline sigmoidoscopy sub-score
                  of at least 2, and disease that extended 15 cm or more from the anal verge.

               -  Steroid dependent patients (Appendix 1)

               -  Steroid naïve or steroid responsive

          7. Patients are planned to start vedolizumab as part of their clinical care.

          8. 5-aminosalicilates (oral or topical) are permitted as long as the dose is stable for
             at least 2 weeks before screening.

          9. Patients with or without previous exposure to anti-TNF agents can be included.
             Patients with previous exposure to anti-TNF must be off infliximab for 8 weeks and off
             adalimumab for 4 weeks.

         10. Anti-diarrheals (eg, loperamide, diphenoxylate with atropine) for control of chronic
             diarrhea are not permitted.The patient must be off anti-diarrheal at the time of
             screening.

         11. Immunosupressants (thiopurines or methotrexate) must be stopped 4 weeks prior to
             starting the study medications.

         12. Patients with previous Clostridium Difficile infection can be included as long as they
             received a full course of therapy and have a negative Clostridium Difficile PCR test
             and are infection free for 60 days prior to screening.

        Exclusion Criteria:

          1. Positive stool test for parasites or stool culture for pathologic bacteria within 30
             days prior to enrollment.

          2. Evidence or history of Clostridium Difficile infection within 60 days prior to
             enrollment.

          3. Active Cytomegalovirus (CMV) infection evidenced by a positive CMV PCR in serum and/or
             positive immunohistochemistry stain in colonic tissue.

          4. Uncontrolled hypertension.

          5. Chronic kidney disease (defined as a glomerular filtration rate < 60 mL/min,
             calculated using the Modification of Diet in Renal Disease (MDRD) formula)

          6. Chronic liver disease.

          7. A refractory electrolyte disorder (e.g. hypomagnesemia).

          8. Persistent hypomagnesemia that does not respond to oral magnesium supplementation
             defined as a value <1.3 mEq/L in two separate readings, despite the administration of
             oral magnesium [10 meq of slow-release magnesium chloride three times per day for 48
             hours].

          9. Persistent hypophosphatemia defined as levels <2.2 mg/dL in two separate readings, 48
             hours apart despite phosphate supplementation (sodium phosphate/potassium phosphate
             500 mg up to three times daily for 48 hours).

         10. Creatinine values of 1.5 mg/dL in 2 separate readings.

         11. Established diagnosis of diabetes mellitus.

         12. Clinical or radiological evidence of megacolon.

         13. Intestinal perforation, or abdominal abscess within 3 months prior to enrollment.

         14. Active clinically significant bacterial infection (within 30 days of enrollment).

         15. Personal history of total or sub-total colectomy.

         16. Current Pregnancy or lactation.

         17. Unstable or uncontrolled medical disorder.

         18. Personal history of malignant neoplasm.

         19. Inability to give informed consent.

         20. History of alcohol or illicit drug abuse in the previous 6 months to enrollment.

         21. Patient that have received any experimental drug within 6 months prior to enrollment.

         22. Patients with previous exposure to vedolizumab, cyclosporine or tacrolimus.

         23. Personal history of congenital or acquired immunodeficiency (eg, common variable
             immunodeficiency, human immunodeficiency virus [HIV] infection, organ transplantation)
             excluding pharmacologic immunosuppressant.

         24. Any of the following laboratory abnormalities during the screening period:

               1. Hemoglobin level <9 g/dL

               2. WBC count <3 × 109/L

               3. Lymphocyte count <0.5 × 109/L

               4. Platelet count <100 × 109/L or >1200 × 109/L

               5. Alanine aminotransferase (ALT) or aspartate aminotransferase (AST) >2 × the upper
                  limit of normal (ULN)

         25. To avoid interactions, patients on medications that induce or inhibit the Cytochrome
             p450 family 3, subfamily A (CYP3A) will be excluded. CYP3A inducers and inhibitors are
             shown in Appendix 3
      