OBJECTIVES:

The objective of this study was to evaluate the cost-utility of avacopan in combination with cyclophosphamide or rituximab compared with glucocorticoids (GC) and cyclophosphamide or rituximab for patients with anti-neutrophil cytoplasmic antibody (ANCA)–associated vasculitis (AAV) in the UK National Health Service (NHS).

METHODS:

A state-transition Markov model was designed to reflect clinical practice for induction of remission in patients with ANCA-associated vasculitis, with up to three induction courses. The model comprises 9 health states: an active disease state where patients start, three remission and three relapse states, end-stage renal disease (ESRD) and death. Additionally, patients can experience GC-related adverse events. The clinical efficacy for avacopan was based on the ADVOCATE trial, and included disease remission at 26, 52 and 60 weeks, change in estimated glomerular filtration rate (eGFR) and health-related quality of life. The transition probabilities to ESRD were sourced from literature. Cost data were obtained from published literature, including adverse events, and clinical management of AAV. Benefits were expressed as quality-adjusted life years (QALYs). Costs were reported in 2021 British pounds (£).

RESULTS:

The incremental cost and incremental QALY of a regimen including avacopan compared to GC, both as an add on to cyclophosphamide (35%) or rituximab (65%), were £5,100 and 0.26 QALY, respectively. The results show an incremental cost-effectiveness ratio of £19,615 per additional QALY gained, which is lower than the willingness-to-pay threshold of £20,000 per QALY in the UK. The model results were sensitive to the eGFR improvement reported in the ADVOCATE trial. Other parameters which contributed to model uncertainty were the discount rate for outcomes and costs, and the cost of maintenance dialysis, which is the main component of the cost of ESRD.

CONCLUSIONS: Avacopan in combination with cyclophosphamide and rituximab is a new cost-effective option for AAV patients in the NHS.