Background and objectives: Despite existing therapies, people with lupus nephritis progress to kidney failure and have reduced life expectancy. Belimumab and voclosporin are two new disease-modifying therapies recently approved for the treatment of lupus nephritis.
Design, setting, participants, & measurements: A de novo economic model was developed to estimate the cost-effectiveness of these therapies, including the following health states: "complete response," "partial response," and "active disease" defined by eGFR and proteinuria changes, kidney failure, and death. Short-term data and mean cohort characteristics were sourced from pivotal clinical trials of belimumab (the Belimumab International Study in Lupus Nephritis) and voclosporin (the Aurinia Urinary Protection Reduction Active-Lupus with Voclosporin trial and Aurinia Renal Response in Active Lupus With Voclosporin). Risk of mortality and kidney failure were on the basis of survival modeling using published Kaplan-Meier data. Each drug was compared with the standard of care as represented by the comparator arm in its respective pivotal trial(s) using US health care sector perspective, with a societal perspective also explored.
Results: In the health care perspective probabilistic analysis, the incremental cost-effectiveness ratio for belimumab compared with its control arm was estimated to be approximately $95,000 per quality-adjusted life year. The corresponding incremental ratio for voclosporin compared with its control arm was approximately $150,000 per quality-adjusted life year. Compared with their respective standard care arms, the probabilities of belimumab and voclosporin being cost effective at a threshold of $150,000 per quality-adjusted life year were 69% and 49%, respectively. Cost-effectiveness was dependent on assumptions made regarding survival in response states, costs and utilities in active disease, and the utilities in response states. In the analysis from a societal perspective, the incremental ratio for belimumab was estimated to be approximately $66,000 per quality-adjusted life year, and the incremental ratio for voclosporin was estimated to be approximately $133,000 per quality-adjusted life year.
Conclusions: Compared with their respective standard care arms, belimumab but not voclosporin met willingness-to-pay thresholds of $100,000 per quality-adjusted life year. Despite potential clinical superiority in the informing trials, there remains high uncertainty around the cost-effectiveness of voclosporin.
Keywords: United States; belimumab; cost-effectiveness analysis; cyclophosphamide; economic analysis; lupus nephritis; mycophenolate; voclosporin.
Copyright © 2022 by the American Society of Nephrology.