Effectiveness and Tolerance of IV vs SC Biological Drugs in Gastrointestinal Diseases

Inclusion Criteria

• •Age ≥ 18 years;
• •Confirmed diagnosis of IBD (Crohn's disease, ulcerative colitis or indeterminate colitis)
• •Intravenous therapy with vedolizumab or infliximab; OR
• •Patients who for clinical reasons initiated subcutaneous vedolizumab or infliximab therapy at least 2 and up to 8 weeks after intravenous therapy with the same drugs for the prospective cohort and patients on subcutaneous vedolizumab and infliximab therapy for more than 8 weeks after intravenous therapy with the same drugs for the retrospective cohort;
• •Stable (at least 12 weeks) steroid-free IBD clinical remission, defined as a finding of Harvey Bradshaw Index3 (HBI) scores \< 5 or Partial Mayo Score 4.5 (PMS) \< 2 for patients with Crohn's disease or colitis ulcerative, respectively, assessed at the time of switching the drug to subcutaneous administration;
• •Ability to sign informed consent for participation in the study and to comply with the schedule of scheduled visits.