Ulcerative colitis (UC) is a chronic remitting and relapsing inflammatory bowel disease. The pathogenesis is multifactorial, involving genetic predisposition, epithelial barrier defects, dysregulated immune responses, and environmental factors. It is diagnosed through colonoscopy and histological evidence of mucosal inflammation involving predominantly the rectum and potentially extending continuously up to the proximal segments of the colon. The patients affected present with severe abdominal pain, bloody diarrhea together with extraintestinal manifestations such as peripheral arthritis, pyoderma gangrenosum, erythema nodosum, ankylosing spondylitis and many others. The last 20 years have been profitable from the therapeutical point of view thanks to the advent of biological drugs which are derived from a living organism or its products including antibodies, interleukins and other molecules capable to target specific cellular pathways and to modulate different mechanisms such as blocking the actions of cytokines or white cells movement in the gut. More recently new promising alternatives seems to be the so-called small molecule drugs which are chemically derived low molecular weight compounds capable to enter the cell to regulate its functions and more generally biological processes like inflammation. In the last years, the therapeutic offer for ulcerative colitis patients has been enriched with the advent of biologics with different mechanism of action and very recently with the availability of the small molecules. Currently the available therapeutic options for ulcerative colitis include topic and systemic mesalazine, topic and systemic glucocorticoids, immunosuppressants (thiopurines), biological drugs (anti-tumor necrosis factor α (TNFα), inhibitor of α4β7 integrin, anti-IL12-23) and small molecules (JAK inhibitors). However, if on the one hand the therapeutical enrichment has clearly improved the disease rate control, still there is the need to perform sequencing study to stratify the available options to provide the best and most appropriate patient-oriented management.

This is an observational, retrospective, international multicenter study on the comparison of ustekinumab (anti-IL12-23) and tofacitinib (pan JAK inhibitor) used as third-line therapy in UC cases.

The aim of this retrospective multicentric observational study is to determine which between ustekinumab (anti-IL12-23) and tofacitinib (pan JAK inhibitor) as third-line therapy in UC cases refractory to both anti-TNFα and vedolizumab (inhibitor of α4β7 integrin) is the best compound to achieve disease control. The primary goal is to compare the hospitalization rate, surgery rate, drug optimization rate and the drug discontinuation rate, as a composite primary objective, in patients on either of the two drugs.

Subjects received the drugs, as per clinical practice, starting from their marketing authorization up to February 2022. The data will be collected starting from the time of diagnosis of UC up to last follow-up. This study does not require specific procedures as it is intended for the collection and analysis of data from treatments already carried out.

Inclusion Criteria:

• Age ≥18 years;
• Established diagnosis of UC, defined according to ECCO standard of care
• Documented failure to both anti-TNFα (irrespectively of the number) and vedolizumab
• Ustekinumab or tofacitinib as third-line therapy
• Last follow-up at 24 +/-4 weeks from the start of Ustekinumab or tofacitinib

Exclusion Criteria:

• Patients with unclassified colitis or Crohn disease

Approximately 100 patients with a diagnosis of UC, defined according to ECCO standard of care and who have been treated with ustekinumab (anti-IL12-23) or tofacitinib (pan JAK inhibitor) and have a follow-up at 24 +/- 4 weeks from the start of the third line therapy. Patients will be enrolled from all the 17 centers participating to this international multicenter study Patients will be managed in each IBD center according to standard of care. All centers will be asked to fill the case report form (CRF) with all patients' data.