Filgotinib is in clinical development for the treatment of patients with moderately to severely active ulcerative colitis. Ulcerative colitis is a type of inflammatory bowel disease that causes inflammation and ulcers in the bowel and rectum which can cause diarrhoea, abdominal pain and faecal urgency or incontinence. The symptoms of ulcerative colitis often follow a pattern of relapse and remission where they have periods of none or mild symptoms followed by periods of increased symptoms flare-up (‘active’). There are no curative therapies for ulcerative colitis and current treatment aims to relieve symptoms during a flare-up and maintain remission by preventing symptoms from returning.
Filgotinib is administered orally in tablet form. It works by binding to and blocking a pathway of the JAK enzymes, which mediates the signalling and activity of many molecules involved in inflammation and immune mediated diseases. Filgotinib is highly selective for JAK1 so it may have fewer adverse effects compared to other non-selective drugs that block all JAK enzymes. If licensed, filgotinib will offer an additional treatment option for the induction and maintenance of remission in adults with moderately to severely active ulcerative colitis.
Etrolizumab is a new monoclonal antibody (an immune protein) delivered by subcutaneous injection. The treatment works by targeting molecules called integrins to control the immune response and prevent the accumulation of immune molecules, which cause inflammation in individuals with a form of ulcerative colitis where inflammation is not mediated by a signalling protein called tumour necrosis factors (TNF) alpha (‘non-TNF-α’) and who are therefore intolerant to TNF blockers. This represents a new target group as current therapies focus mainly on anti-TNF inflammation. In one study, etrolizumab showed a greater reduction of intestinal lymphocyte infiltration in comparison to standard treatment.