A Study of Tofacitinib in Patients With Ulcerative Colitis in Stable Remission

Inclusion Criteria:

- Currently enrolled in Study A3921139 receiving CP-690,550 10 mg BID for at least 2
years consecutively.

- In stable remission on CP-690,550 10 mg BID

- Agree to use highly effective contraception

- Negative pregnancy test

- Comply with visits, treatments, lab tests, diary and other study procedures

- Signed and dated informed consent document.

Exclusion Criteria:

- Subjects who were initially assigned to tofacitinib 10 mg BID at baseline of Study
A3921139 whose tofacitinib dose was reduced to 5 mg BID due to safety or efficacy.

- Presence of indeterminate colitis, microscopic colitis, ischemic colitis, infectious
colitis or findings suggestive of Crohn's disease

- Likely to require surgery for ulcerative colitis during study

- Expected to receive any prohibited medication

- Expected to receive live or attenuated virus vaccination during study

- Women who are pregnant or breastfeeding or planning to become pregnant during the
study

- Evidence of colonic malignancy or any dysplasia

- Acute or chronic medical or psychiatric condition that may increase risk of
participation

- Investigator site staff member

- Subjects likely to be uncooperative or unable to comply with study procedures

- Participation in other studies involving investigational drugs during study