Phase II Study of Hemay005 in Patients With Active Ulcerative Colitis

Inclusion Criteria: * Willing to participate in the trial and signing the informed consent forms; * Age ≥18 years old, male or female; * Diagnosed as ulcerative colitis (UC) ≥ 3 months at screening with clinical manifestations and evidence of endoscopy and confirmed by histopathological reports; * Expansion of the affected bowel segment beyond the rectum confirmed on endoscopy (affected bowel segment≥15cm); * Moderate to severe ulcerative colitis with Modified Mayo clinical score (MMCS)≥ 4 points and ≤9 points, the Endoscopy subscore ≥ 2 points within 14 days before randomization and Stool Frequency subscore ≥ 1 point; * UC treatment failure or intolerance (intolerance is defined as the discontinuation of drug use due to adverse reactions judged by the investigators) experienced by patients using at least one of the following: Oral administration of sulfasalazine (SASP) and/or 5-aminosalicylic acid (5-ASA); Oral administration of corticosteroids; Azathioprine or 6-mercaptopurine; Anti-TNF-α treatment: infliximab or adalimumab, etc.; - If the patient is using the following drugs to treat ulcerative colitis at the time of screening, it is necessary to receive stable treatment during the screening period and the following requirements during the study period are as follows: Oral administration of sulfasalazine (SASP) and/or 5-aminosalicylic acid (5-ASA) maintaining stable for at least ≥ 2 weeks prior to endoscopy during the screening period and maintaining stable during the st…