Certolizumab pegol is a recombinant, humanized antibody Fab' fragment with specificity for human tumour necrosis factor alpha that is indicated for the treatment of adult patients with moderate-to-severe plaque psoriasis who are candidates for systemic therapy. Certolizumab pegol is available as a solution for subcutaneous injection in a single-use, pre-filled syringe or single-use pre-filled autoinjector containing 200 mg/mL of certolizumab pegol. The recommended dose is 400 mg administered via subcutaneous injection every two weeks. A dose of 400 mg at week 0 and week 4 followed by 200 mg every two weeks thereafter may be considered. At the manufacturer’s submitted price of $664.51 per pre-filled syringe or autoinjector, and at the recommended dose of 400 mg every two weeks, the annual cost of certolizumab pegol is $34,555, whereas, at a 200 mg dose, the annual cost during the first year is $19,271 and $17,277 thereafter. The manufacturer submitted a cost-utility analysis based on a Markov state–transition model comparing certolizumab pegol with best supportive care (BSC) and the following biologic therapies reimbursed in Canada for moderate-to-severe plaque psoriasis: adalimumab, brodalumab, etanercept, guselkumab, infliximab (branded), ixekizumab, secukinumab, and ustekinumab. BSC consisted of treatment with cyclosporine, methotrexate, acitretin, and/or phototherapy. The analysis was conducted from a Canadian publicly funded health care payer perspective using two-week cycles over a lifetime horizon (defined as the period over which more than 99% of the modelled cohort is predicted to have died). An annual discount rate of 1.5% was applied to both costs and benefits. The model had two time periods: the initial period, from treatment initiation to the initial assessment of treatment response (i.e., 10 to 16 weeks), and the maintenance period.