Clinical Trial of TQH3906 Capsules for the Treatment of Adult Patients With Moderately to Severely Active Ulcerative Colitis or Crohn's Disease

Inclusion Criteria: * Age between 18-75 years (inclusive of both 18 and 75), regardless of gender. * Diagnosed with ulcerative colitis or Crohn's disease for ≥3 months, as assessed by histological or endoscopic examination prior to screening. * Active moderate to severe UC or CD. * Subjects must have failed at least one of the following drug treatments for UC or CD or be intolerant: oral aminosalicylates, oral corticosteroids, immunosuppressants, biologics, etc. * If subjects are using the following drugs for UC or CD at the time of screening, their treatment should be stabilized with oral aminosalicylates for at least 3 weeks before the first dose of the trial medication, or stabilized with oral systemic corticosteroids for at least 2 weeks before the first dose of the trial medication, and maintain a stable dose during the trial period. * If oral aminosalicylate or combined hormone therapy has been discontinued recently, it must be discontinued for at least 2 weeks prior to the pre-randomization endoscopy. * Subjects (including partners) are willing to voluntarily take appropriate and effective contraceptive measures from the time of screening until 3 months after the last administration of the study medication. * Before the trial, understand in detail the nature, significance, potential benefits, possible inconveniences, and potential risks of the trial, understand the research procedures, and voluntarily sign the informed consent form. Exclusion Criteria: * Pregnant or…