Abstract: FR-PO882

Phosphate Binder Use and Cost Trends in US Dialysis Patients

Session Information

Category: Dialysis

  • 607 Dialysis: Epidemiology, Outcomes, Clinical Trials - Non-Cardiovascular

Authors

  • St. Peter, Wendy L., University of MInnesota, Minneapolis, Minnesota, United States
  • Wazny, Lori, Manitoba Renal Program, Winnipeg, Manitoba, Canada
  • Weinhandl, Eric D., University of MInnesota, Minneapolis, Minnesota, United States
Background

Phosphate binder costs for US dialysis patients having Medicare Part D was almost $1 billion in 2014. Our objectives were to examine current trends in use and cost data for phosphate binders and to determine gross Medicare Part D costs per equivalent phosphate binding dose.

Methods

Using data from United States Renal Data System, we report trends in phosphate binder use and costs for Medicare-covered dialysis patients with Medicare Part D prescription drug coverage from 2006-2013. We identified all medication fills for phosphate binders (calcium acetate, lanthanum carbonate, sevelamer carbonate, and sevelamer hydrochloride) and all Part D-covered drugs. For each year, we calculated percent of patients using phosphate binders (overall and by binder), weighted by cumulative follow-up time per patient, cumulative gross costs, gross costs per patient-year and gross costs per user-year. For each phosphate binder, we estimated gross costs per calcium carbonate-equivalent gram by applying relative phosphate binding capacities equal to 1.00 for calcium acetate, 2.00 for lanthanum, and 0.75 for sevelamer products.

Results

Number of dialysis patients with Medicare Part D coverage filling phosphate binder prescriptions steadily increased from 174,974 in 2006 to 263,404 in 2013 (50% cumulative increase), while percentages filling phosphate binder prescriptions remained stable at around 75% while gross costs per user-year for phosphate binders increased from $1433 to $3716 (159% cumulative increase, or 15% year-over-year increase). Gross costs per user-year for all other Part D-covered prescription medications in dialysis patients cumulatively increased by 44% (5.4% year-over-year growth). Between 2006 and 2013, gross costs per user-year for calcium acetate, sevelamer carbonate, and lanthanum carbonate increased by 153%, 284%, and 307%, respectively. Adjusted for relative phosphate binding capacity, gross costs of calcium acetate, lanthanum carbonate, and sevelamer carbonate were $0.79, $4.67, and $4.85, respectively, per one calcium carbonate-equivalent gram in 2013.

Conclusion

Growth in cost of phosphate binders outpaced growth in costs of other Medicare Part D medications in dialysis patients. To achieve an equal degree of phosphorus control in an average patient, Medicare expended roughly 6 times as much on sevelamer carbonate and lanthanum carbonate as on calcium acetate in 2013.