Cost-Effectiveness Analysis of Sparsentan for the Treatment of Immunoglobulin A Nephropathy in Spain
Author(s)
Marian Goicoechea, Dr1, Eduardo Parra, Dr2, Mónica Climente Martí, PhD3, Antonio Ramirez de Arellano Serna, MSc, DPhil4, OLGA RUIZ ANDRES, PhD, MBA5, Clarissa Sancho, MSc6, Noemi Lopez, MSc6, ELISENDA POMARES MALLOL, MSc6.
1Hospital General Universitario Gregorio Marañón, Madrid, Spain, 2Hospital Universitario Miguel Servet, Zaragoza, Spain, 3Hospital Universitario Dr. Peset, Valencia, Spain, 4CSL Vifor, Glattbrugg, Switzerland, 5Vifor Pharma, Barcelona, Spain, 6Cencora Spain, Barcelona, Spain.
1Hospital General Universitario Gregorio Marañón, Madrid, Spain, 2Hospital Universitario Miguel Servet, Zaragoza, Spain, 3Hospital Universitario Dr. Peset, Valencia, Spain, 4CSL Vifor, Glattbrugg, Switzerland, 5Vifor Pharma, Barcelona, Spain, 6Cencora Spain, Barcelona, Spain.
OBJECTIVES: Immunoglobulin A nephropathy (IgAN) is a rare autoimmune disease and a leading cause of kidney failure. This study evaluated the cost-effectiveness of sparsentan versus irbesartan for adults with IgAN and significant proteinuria (UPE ≥1.0 g/day or UPCR ≥0.75 g/g) from the Spanish National Health System perspective.
METHODS: A 16-state Markov model was developed to simulate disease progression in patients treated with sparsentan versus irbesartan over a 54-year time horizon. The model included four levels of proteinuria (UPE: <0.5; 0.5-1.0; 1.0-2.0; and >2.0 g/day), across three chronic kidney disease (CKD) stages (G1-2, G3 and G4), end-stage renal disease (ESRD: pre-renal replacement therapy, transplant and dialysis), and death. Baseline characteristics were obtained from the PROTECT trial. Transition probabilities for UPE were based on 108-week PROTECT data, while movements among CKD stages were derived from the long-term UK National Registry of Rare Kidney Diseases data. ESRD transitions were calculated using data from the Spanish Registry of Renal Patients, expert opinion, and market research. A discount rate was applied to costs and health outcomes. Costs (€, 2025) included drug acquisition, disease and ESRD and adverse events management. Health outcomes were measured in quality-adjusted life years (QALYs). Deterministic and probabilistic sensitivity analyses tested model robustness.
RESULTS: Compared to irbesartan, sparsentan delayed the progression of CKD and ESRD in patients with IgAN, resulting in an increase in QALYs (1.44 QALY/patient). Although sparsentan incurred higher drug acquisition costs, these were partially offset by savings in ESRD management (€ 100,676/patient). At a willingness-to-pay threshold for rare diseases in Spain of €60,000 per QALY gained, sparsentan proved to be cost-effective. Sensitivity analyses confirmed the robustness of these results.
CONCLUSIONS: Sparsentan represents a cost-effective treatment option for IgAN patients in Spain, improving outcomes by delaying CKD progression and reducing the risk of ESRD, a costly condition that significantly impairs quality-of-life.
METHODS: A 16-state Markov model was developed to simulate disease progression in patients treated with sparsentan versus irbesartan over a 54-year time horizon. The model included four levels of proteinuria (UPE: <0.5; 0.5-1.0; 1.0-2.0; and >2.0 g/day), across three chronic kidney disease (CKD) stages (G1-2, G3 and G4), end-stage renal disease (ESRD: pre-renal replacement therapy, transplant and dialysis), and death. Baseline characteristics were obtained from the PROTECT trial. Transition probabilities for UPE were based on 108-week PROTECT data, while movements among CKD stages were derived from the long-term UK National Registry of Rare Kidney Diseases data. ESRD transitions were calculated using data from the Spanish Registry of Renal Patients, expert opinion, and market research. A discount rate was applied to costs and health outcomes. Costs (€, 2025) included drug acquisition, disease and ESRD and adverse events management. Health outcomes were measured in quality-adjusted life years (QALYs). Deterministic and probabilistic sensitivity analyses tested model robustness.
RESULTS: Compared to irbesartan, sparsentan delayed the progression of CKD and ESRD in patients with IgAN, resulting in an increase in QALYs (1.44 QALY/patient). Although sparsentan incurred higher drug acquisition costs, these were partially offset by savings in ESRD management (€ 100,676/patient). At a willingness-to-pay threshold for rare diseases in Spain of €60,000 per QALY gained, sparsentan proved to be cost-effective. Sensitivity analyses confirmed the robustness of these results.
CONCLUSIONS: Sparsentan represents a cost-effective treatment option for IgAN patients in Spain, improving outcomes by delaying CKD progression and reducing the risk of ESRD, a costly condition that significantly impairs quality-of-life.
Conference/Value in Health Info
2025-11, ISPOR Europe 2025, Glasgow, Scotland
Value in Health, Volume 28, Issue S2
Code
EE220
Topic
Economic Evaluation
Disease
Rare & Orphan Diseases