Retrospective Observational Comparison Study Between Ustekinumab and Tofacitinib as Third Line Therapy in a Multicenter Cohort of Patients With Refractory Ulcerative Colitis.

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.