OBJECTIVES: Chronic kidney disease associated pruritus (CKD-aP) is linked to poor health-related quality of life (HRQoL), as well as increased risks of adverse health outcomes. Difelikefalin was demonstrated to be an efficacious treatment for moderate to severe CKD-aP in two phase III trials: KALM-1 and KALM-2. The objective of this study was to estimate the cost-effectiveness of difelikefalin in addition to best supportive care (BSC) for the treatment of adults with moderate to severe CKD-aP undergoing in-centre haemodialysis, from a UK payer perspective.

METHODS: A lifetime Markov model comprising five health states defined by itch severity was constructed to estimate costs and outcomes for patients treated with difelikefalin plus BSC or BSC alone. CKD-aP progression was modelled based on 5-D Itch scale severity measurements from the KALM trials. Mortality and transplant rates were modelled using time-dependent probabilities from the UK Renal Registry. Relative risk of hospitalisation and mortality were applied based on itch severity, informed by the Dialysis Outcomes and Practice Patterns Study (DOPPS). Utility estimates and costs were sourced from literature and the NHS cost collection, and discounted at 3.5% annually.

RESULTS: Treatment with difelikefalin with BSC compared with BSC alone was associated with increased life expectancy (0.11 years per person) and increased quality adjusted life years (QALYs, 0.26 per person), at an incremental cost of £7,814 per person. Benefits were driven by reductions in itch severity and consequently improved HRQoL and reduced mortality risk, along with reductions in healthcare resource use and concomitant medications. Difelikefalin was estimated to be cost-effective at a willingness-to-pay threshold of £30,000/QALY at a cost of £31.90/vial.

CONCLUSIONS: Difelikefalin plus BSC is a cost-effective treatment for CKD-aP versus BSC alone, with the potential to ameliorate the significant burden CKD-aP imposes on patients in the UK.