OBJECTIVES: To estimate the cost per responder (CPR) of currently approved biologic and subsequent entry biologic (SEB) agents in achieving reductions in the Psoriasis Area and Severity Index (PASI) score at the end of the induction period of therapy for adult patients with moderate-to-severe plaque psoriasis in Canada.

METHODS: A literature review identified a published network meta-analysis evaluating relative effects for improvement from baseline (PASI 75/90/100) across treatments at the end of the induction period (10 to 16 weeks). The CPR was estimated as the drug acquisition costs during the induction period multiplied by the number needed to treat (NNT) for achieving PASI 75, 90, or 100 for the following treatments: adalimumab (innovator and SEB), brodalumab, bimekizumab, certolizumab pegol, etanercept (innovator and SEB), guselkumab, infliximab (innovator and SEB), ixekizumab, risankizumab, secukinumab, tildrakizumab, ustekinumab. Canadian costs of treatments were estimated based on Health Canada approved regimens and Ontario wholesale unit prices obtained from the DeltaPA IQVIA database in December 2022. The primary analysis was the CPR for PASI 90, with PASI 75 and 100 as secondary analyses. Sensitivity analysis was performed from the perspective of provincial public drug plans.

RESULTS:

The PASI 90 CPR were as follows: brodalumab $7,327; adalimumab SEB $10,792; guselkumab $13,952; infliximab SEB $14,124-$15,041; adalimumab innovator $18,185; secukinumab $19,051; ixekizumab $19,377; bimekizumab $19,825; certolizumab 200 $19,935; risankizumab $20,727; ustekinumab $21,128; certolizumab 400 $25,597; etanercept SEB $26,664; tildrakizumab $27,636; infliximab innovator $28,294; etanercept innovator $44,918. Brodalumab and etanercept innovator consistently represented the lowest and highest CPR for PASI 75 and 100 respectively.

CONCLUSIONS:

Despite the availability of various biologic and SEB therapies for plaque psoriasis in Canada, the range of CPR estimates vary significantly, with brodalumab having the lowest CPR across all PASI scores during the induction period. Using therapies with more favorable CPR may translate into cost-saving opportunities.