A projected cost-utility analysis of avacopan for the treatment of antineutrophil cytoplasmic antibody-associated vasculitis in Spain

ABSTRACT

Background

Antineutrophil cytoplasmic antibody-associated vasculitis (AAV) are rare autoimmune diseases characterized by inflammation of blood vessels. This study aimed to assess the cost-utility of avacopan in combination with rituximab (RTX) or cyclophosphamide (CYC) compared with glucocorticoids (GC) for the treatment of severe, active AAV in Spain.

Methods

A 9-state Markov model was designed to reflect the induction of remission and sustained remission of AAV over a lifetime horizon. Clinical data and utility values were mainly obtained from the ADVOCATE trial, and costs (€ 2022) were sourced from national databases. Quality-adjusted life years (QALYs), and incremental cost-utility ratio (ICUR) were evaluated. An annual discount rate of 3% was applied. Sensitivity analyses were performed to examine the robustness of the results.

Results

Avacopan yielded an increase in effectiveness (6.52 vs. 6.17 QALYs) and costs (€16,009) compared to GC, resulting in an ICUR of €45,638 per additional QALY gained. Avacopan was associated with a lower incidence of end-stage renal disease (ESRD), relapse and hospitalization-related adverse events. Sensitivity analyses suggested that the model outputs were robust and that the progression to ESRD was a driver of ICUR.

Conclusions

Avacopan is a cost-effective option for patients with severe, active AAV compared to GC in Spain.

KEYWORDS:

• Avacopan
• competitive C5a receptor antagonist
• cost-utility analysis
• granulomatosis with polyangiitis
• microscopic polyangiitis
• vasculitis

Article highlights

• The aim of this analysis was to assess the cost-utility of avacopan in combination with rituximab or cyclophosphamide compared with glucocorticoids for the treatment of severe, active antineutrophil cytoplasmic antibody-associated vasculitis.

• A Markov model with nine health states based on the ADVOCATE trial data was adapted from a Spanish payer perspective over a lifetime horizon.

• Avacopan was associated with a lower incidence of end-stage renal disease, relapse and hospitalization-related adverse events.

• Avacopan is more effective than glucocorticoids and results in an incremental cost-utility ratio of €45,638/QALY gained.

• Avacopan is a cost-effective treatment option for patients with severe, active antineutrophil cytoplasmic antibody-associated vasculitis compared to glucocorticoids in Spain.

Declaration of interest

A Ramírez de Arellano is employed by CSL Vifor Switzerland. C Escribano is employed by CSL Vifor Spain. E Pomares Mallol and A García Castells are employed by PharmaLex Spain and received financial support from Vifor Pharma Spain for the development of this study. M Macía, M Díaz-Encarnación, and R Solans-Laqué received an honorarium from the sponsor and participated as independent consultants.

The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

Author contributions

All authors contributed to the conception and design of the study. E Pomares Mallol and A García Castells contributed to the analysis and interpretation of the data, and the drafting of the manuscript. M Macía, M Díaz-Encarnación and R Solans-Laqué contributed to the review and editing. All study authors meet the criteria for authorship as outlined by the journal policy and agree for the final version of the manuscript to be published.

Acknowledgments

We thank Susana Romero Yuste from the Rheumatology Service of the Complejo Hospitalario Universitario de Pontevedra (Spain), who provided insight and expertise that greatly assisted this study.

An abstract and poster of some of the material contained in the paper was previously presented at ISPOR Europe 2022, Vienna (Austria), 6-9 November 2022.

Reviewer disclosures

A reviewer on this manuscript has disclosed that they are on the Advisory Board of Amgen. Peer reviewers on this manuscript have no other relevant financial relationships or otherwise to disclose.

Supplementary material

Supplemental data for this article can be accessed online at https://doi.org/10.1080/14737167.2023.2297790

Additional information

Funding

This cost-utility study has been funded by Vifor Fresenius Medical Care Renal Pharma.