NAZA - Nottingham/Astra ZenecA Prospective IBD Cohort Study

Inclusion criteria

• \. Provision of signed and dated, written informed consent before any study specific procedures
• AND
• a. Patients of at least 16 years of age with active Crohn's disease defined as: CRP \> = 5 mg/L OR FCP \> = 250 μg/g OR Visible ulcerations on ileocolonoscopy with a total SES-CD \> = 7, or \> = 4 if disease is confined to the terminal ileum OR visable active disease on cross-sectional imaging. Are switching to a new mechanism of action (MOA) onto anti-TNF therapy or ustekinumab or upadacitinib
• b. Patients of at least 16 years (no upper age limit) with active UC defined as: CRP \> = 5 mg/L OR FCP \> = 250 μg/g OR Mayo endoscopy subscore \> = 2. Are switching to a new mechanism of action (MOA) onto either anti-TNFα therapy or vedolizumab
• c. Non-IBD participants who are attending for a lower GI colonoscopy at any participating site. On any hospital/ medical/ clinical screening list or any other appropriate list with no pathology found on examination.

Exclusion criteria

• Inability to give informed consent
• Any positive result from previous screening for serum hepatitis B surface antigen, hepatitis C or human immunodeficiency virus (HIV)
• An ongoing infection requiring treatment
• Clinical evidence of active COVID infection and/or evidence of active COVID determined by local standard care procedures
• Participation in a clinical study with pharmacological intervention within 3 months prior to Baseline visit.
• Current diagnosis of cancer
• Having received a solid organ or stem cell transplant
• Having received a transfusion of blood, plasma, or platelets within 120 days prior to enrolment
• Confirmed pregnancy at time of enrolment
• For non-IBD participants: A prior history of IBD (CD, UC, microscopic colitis, indeterminate colitis or IBD unspecified)
• Clinical judgement by the investigator that the patient should not participate in the study
• Under 16yrs of age