For the treatment of ulcerative colitis disease in patients who meet the following criteria: 1. Moderate disease a. Mayo score between 6 and 10 (inclusive) AND b. Endoscopic* subscore of 2 AND c. Failed 2 weeks of oral prednisone at daily doses greater than or equal to 40mg (or a 1 week course of IV equivalent) OR d. Stabilized with 2 weeks oral prednisone at daily doses greater than or equal to 40mg (or 1 week of IV equivalent) but demonstrated that the corticosteroid dose cannot be tapered despite 3 months of AZA/6MP (or where the use of immunosuppressants is contraindicated). 2. Severe disease a. Mayo score greater than 10 AND b. Endoscopy* subscore of greater than or equal to 2 AND c. Failed 2 weeks of oral prednisone at daily doses greater than or equal to 40mg (or 1 week of IV equivalent) OR d. Stabilized with 2 weeks oral prednisone at daily doses greater than or equal to 40mg (or 1 week of IV equivalent) but demonstrated that the corticosteroid dose cannot be tapered despite 3 months of AZA/6MP (or where the use of immunosuppressants is contraindicated). *The endoscopy procedure must be done within the 12 months prior to initiation of treatment. The recommended dosing regimen for induction is 10mg twice daily for at least 8 weeks. Maintenance/Renewal: Maintenance therapy is funded for patients who meet the Ministry initiation criteria and whose disease is maintained at Mayo score less than 6 AND who demonstrate at least 50% reduction in the dose of prednisone compared with the starting dose following the first 6 months of treatment with tofacitinib or be off corticosteroids after the first year of treatment. The recommended dosing regimen is 5mg twice daily. Depending on therapeutic response; 10mg twice daily may also be used for maintenance in some patients. However, the lowest effective dose possible should be used for maintenance therapy to minimize adverse effects.