Tofacitinib (Xeljanz) is an orally administered Janus kinase inhibitor indicated for the treatment of patients with moderately to severely active ulcerative colitis (UC) who have had an inadequate response, loss of response, or intolerance to either conventional UC therapy or a biologic agent. The recommended dosage for tofacitinib is one 10 mg tablet administered twice daily during an induction period lasting at least eight weeks, followed by one 5 mg tablet administered twice daily thereafter during the maintenance phase of treatment once response to treatment has been achieved. Tofacitinib 10 mg twice daily in the maintenance phase may be prescribed to some patients. The product monograph states that tofacitinib should be discontinued if no evidence of benefit is achieved by week 16. At the manufacturer-submitted price of $23.96 per 5 mg tablet and $42.34 per 10 mg tablet, the annual cost of tofacitinib is $19,501 in the first year and $17,442 every year thereafter, based on the recommended dosage for induction and 5 mg twice daily in the maintenance phase. This cost could increase significantly, up to $30,181 per year, in certain populations requiring tofacitinib 10 mg twice daily in the maintenance phase. Tofacitinib 5 mg was previously considered by CADTH Canadian Drug Expert Committee for the treatment of rheumatoid arthritis in 2015 and was recommended to be listed with clinical criteria, with the condition that the drug plan cost for tofacitinib not exceed the drug plan costs for the biologic disease-modifying antirheumatic drugs. The manufacturer submitted a cost-utility analysis comparing tofacitinib plus conventional therapy (a mix of 5-aminosalicylates, corticosteroids, and immunomodulators) with biologic treatments (vedolizumab, infliximab, infliximab biosimilar, adalimumab, and golimumab) plus conventional therapy (same as tofacitinib), as well as continuing conventional therapy (the same mix of 5-aminosalicylates, steroids, and immunomodulators) in patients (≥ 18 years of age) with moderately to severely active UC and an inadequate response to conventional therapy or biological agents. The analysis was conducted over a lifetime time horizon from a Canadian public health care payer perspective. The manufacturer submitted a cohort-level state-transition (Markov) model, in which patients entered the model in an active UC state and started an eight-week induction period with tofacitinib or a biologic comparator plus conventional therapy or continued on conventional therapy alone. At any time in the model, patients could experience a response or clinical remission, or remain in an active UC state (nonresponders), and patients in a clinical remission or response state could lose their response and regress to active UC. Patients in the active UC state could undergo a colectomy at any point; the risk of colectomy differed based on time since UC diagnosis.