Cost Effectiveness of Difelikefalin Compared to Standard Care for Treating Chronic Kidney Disease Associated Pruritus (CKD-aP) in People with Kidney Failure Receiving Haemodialysis

BackgroundChronic kidney disease-associated pruritus (CKD-aP) is associated with an increased risk of depression, poor sleep and reduced health-related quality of life. Two phase III studies (KALM-1 and KALM-2) of difelikefalin showed reduced CKD-aP severity and improved itch-related health-related quality of life in patients with moderate and severe CKD-aP receiving haemodialysis for kidney failure.ObjectiveWe aimed to estimate the cost effectiveness of difelikefalin for patients with CKD-aP receiving haemodialysis for kidney failure compared to standard care from a UK National Health Service perspective.MethodsA cohort model was developed with four health states representing levels of pruritus intensity over time, based on the KALM trials augmented with longer term CKD-aP severity data from another haemodialysis trial (SHAREHD) for standard care. Utilities were estimated from a mapping study of 5-D Itch to EQ-5D-5L in 487 patients receiving haemodialysis, costs were estimated based on resource use alongside the SHAREHD and 2018 unit costs, and inflated to 2021 costs. Costs and quality-adjusted life-years were discounted at 3.5% per annum. A de novo economic model was developed in Microsoft Excel with scenario analyses performed using a range of assumptions.ResultsIn the base-case analysis over a time horizon of 64 weeks, using a placeholder cost of 75 pound per 28-days for difelikefalin, the incremental cost-effectiveness ratio of difelikefalin compared with standard care was 19,558 pound/quality-adjusted life-year (QALY). Scenario analyses resulted in incremental cost-effectiveness ratios that ranged from 10,154 pound/QALY (severe only) to 16,957 pound/QALY (5-year horizon) for difelikefalin compared to standard care. Probabilistic sensitivity analyses suggested difelikefalin has a 48.6% probability of being cost effective at a threshold of 20,000 pound/QALY and a 57.2% probability of being cost effective at a threshold of 30,000 pound/QALY.ConclusionsThe cost effectiveness of difelikefalin in a range of scenarios could make it an important pharmacotherapy to address the high burden of disease and unmet need for treatments associated with CKD-aP in the UK.