Study for the research of predictive factors of response to Tofacitinib therapy in patients with ulcerative rectal colitis.

Lab values

• Clinical findings suggestive of Crohn’s disease. 2. Ulcerative colitis limited to the distal 15 cm of colon. 3. Clinical signs of fulminant colitis, toxic megacolon, or indeterminate, microscopic, ischemic, or infectious colitis. 4. Patients at high risk of thromboembolism: 1) Patients with heart failure 2) Patients with inherited coagulation disorders 3) Patients who have history of venous thromboembolism, either deep venous thrombosis or pulmonary embolism. 4) Patients who use combined hormonal contraceptives or hormone replacement therapy. 5) Patients with malignancy 6) Patients undergoing major surgery 5. Known hypersensitivity/intolerance to tofacitinib (Xeljanz). 6. Presence of Child-Pugh class C hepatic impairment or eGFR<30 ml/min. 7. Chronic HIV, HBV, HCV infections (excluding patients with HCV infection treated with anti-viral agents in which serum HCV-RNA is not detectable). 8. Active TB or history of latent TB that has not been adequately treated, history of symptomatic herpes zoster (HZV) or any history of disseminated herpes simples (HSV) infections. Active opportunistic, clinically significant infections. 9. History of malignancy in the last 5 years. 10. Pregnant or lactating females. 11. Females of reproductive potential who are unwilling to abide by protocol specified contraceptive methods 8as defined by Appendix 1 in the Study protocol)

• Provided written informed consent. 2. >18 years of age 3. Confirmed diagnosis of ulcerative colitis according to international guidelines (ECCO). 4. Patients with moderately-to-severely active disease, as defined as a Mayo score of 6-12, with a rectal bleeding subscore of 1 to 3. 5. Endoscopic Mayo subscore of 2-3. 6. Patients who had failure or intolerant to at least one of the following agents: oral or intravenous glucocorticoids, azathioprine, 6-mercaptopurine, infliximab, golimumab or adalimumab. 7. Because the effects of Tofacitinib on pregnancy are not fully understood, women in childbearing age have to avoid pregnancy. Therefore the above cited patients have to use a suitable contraceptive method such as diaphragm, spiral or contraceptive pill before entering the study, for its entire duration and for 15 weeks after the suspension of the aforementioned drug