Incorporation of Calcimimetics into ESRD Bundle: Changes in Etelcalcetide Utilization and PTH Control Following End of TDAPA Designation

Abstract

Introduction: Calcimimetics, including intravenous etelcalcetide and oral cinacalcet, are often prescribed to hemodialysis patients to prevent complications of elevated parathyroid hormone (PTH) levels. In January 2021, US dialysis reimbursement policy switched from the transitional drug add-on payment adjustment (TDAPA) to an increased bundled payment, with $10.09 per session added for all hemodialysis patients to cover the expense for calcimimetics, whether or not patients are administered etelcalcetide. We leveraged this natural experiment to investigate the impact of this policy change. Methods: This analysis included 713 US in-center hemodialysis patients enrolled in the United States Dialysis Outcomes and Practice Patterns Study (US-DOPPS) who discontinued etelcalcetide during the TDAPA transition period (December 2020 – April 2021). Within a self-matched longitudinal design, within-patient changes in mean PTH, calcium, and phosphorus were assessed in the six months pre- vs. post- etelcalcetide discontinuation, using linear regression adjusted for potential confounders. Results: Etelcalcetide use in US-DOPPS decreased 58%, from 12% to 5% from July 2020 to July 2021; 73% of etelcalcetide discontinuers switched to cinacalcet within six months. Comparing the six months pre- vs. post- etelcalcetide discontinuation, mean PTH levels increased by 107 (95% CI: 80, 133) pg/mL, and the prevalence of PTH >600 pg/mL increased by 15% (95% CI: 11%, 19%), from 28% to 43% overall, and increased from 26% to 49% among Black patients. Mean serum calcium and phosphorus levels increased by 0.42 and 0.16 mg/dL, respectively. Conclusion: Etelcalcetide use decreased substantially after TDAPA ended in January 2021, with most patients switching to cinacalcet. The subsequent increase in PTH levels was swift and sustained, and especially pronounced among Black patients, raising concerns about disparities and potential downstream impact on clinical outcomes. Despite the spirit of the policy change, the flat per-treatment increased payment may have inadvertently created a financial incentive to restrict patient access to a more effective therapy, and potentially stifle drug innovation.