A Phase II Study in Patients With Moderate to Severe Active Ulcerative Colitis.

A Phase II Randomized, Placebo Controlled, Double-blind, 4 Arms Dose-ranging Study to Evaluate the Efficacy and Safety of SHR0302 Compared to Placebo in Patients With Moderate to Severe Active Ulcerative Colitis.

The proposed study is a randomized, double-blind,placebo-controlled, multicenter phase II study to investigate the safety and efficacy of SHR0302 in patients with moderate to severe active ulcerative colitis. The study aims to evaluate the optimal dose of SHR0302 and time needed to induce clinical response in active ulcerative colitis patients.

This is an 8+8 weeks study, in which participants who complete the first 8 weeks treatment phase, will have the option to enter a blinded active arms 8-week extension phase. Early withdrawn subjects during the first treatment phase can not enter the extension phase. The total duration of the study participation, including extension and follow-up, will be approximately 18 weeks.

SHR0302 is a Janus kinase 1(JAK1) inhibitor, capable of blocking Janus kinase-signal transducer and activator of transcription (JAK-STATs) pathway and controlling inflammation. Therefore it has the potential to be a treatment for ulcerative colitis.

Inclusion Criteria:

• Male and Female subject age ≥ 18 and ≤75 years of age at randomization.
• Active ulcerative colitis with a 9-point modified Mayo score of 5 to 9 points and endoscopic subscore of 2 to 3 (The duration of the time between endoscopy and baseline should not exceed 10 days and allow central over read turn over before randomization).
• Subject should have at least three-month history of Ulcerative Colitis diagnosis at randomization.

Exclusion Criteria:

• Diagnosis of indeterminate colitis, or clinical findings suggestive of Crohn's disease.
• Subjects with ulcerative colitis, which is confined to a proctitis (distal 15 cm or less).
• Treatment naïve subjects diagnosed with ulcerative colitis (without previous exposure to treatment).