ASN's Mission

To create a world without kidney diseases, the ASN Alliance for Kidney Health elevates care by educating and informing, driving breakthroughs and innovation, and advocating for policies that create transformative changes in kidney medicine throughout the world.

learn more

Contact ASN

1401 H St, NW, Ste 900, Washington, DC 20005


The Latest on Twitter

Kidney Week

Abstract: SA-PO434

Indirect Comparison of Sodium Zirconium Cyclosilicate versus Patiromer in the Treatment of Hyperkalemia through 48 Hours

Session Information

Category: Chronic Kidney Disease (Non-Dialysis)

  • 304 CKD: Epidemiology, Outcomes - Non-Cardiovascular


  • Betts, Keith, Analysis Group, Inc., Boston, Massachusetts, United States
  • Woolley, J. Michael, ZS Pharma Inc., San Mateo, California, United States
  • Song, Yan, Analysis Group, Inc., Boston, Massachusetts, United States
  • Gao, Wei, Analysis Group, Inc., Boston, Massachusetts, United States
  • Wu, Eric, Analysis Group, Inc., Boston, Massachusetts, United States

Two agents have completed phase 3 trials for treatment of hyperkalemia; patiromer which was approved by US FDA in 2015 and sodium zirconium cyclosilicate (ZS) which is an investigational medication. An indirect treatment comparison was conducted to compare efficacy of ZS and patiromer in lowering serum potassium [K+] after 48 hours of treatment.


To compare mean [K+] after 48 hours of treatment, a matching-adjusted indirect comparison (MAIC) was conducted using patient-level data for patients treated with 10g ZS from the ZS-003 and ZS-004 trials and published aggregate data of patiromer from the OPAL-HK trial. Inclusion/exclusion criteria of the OPAL-HK trial were applied to ZS trials to derive a subset of patients comparable to those in the OPAL-HK trial. To adjust for cross-trial differences, patients from ZS trials were reweighted using the method of moments to exactly match baseline characteristics reported in OPAL-HK.


Applying inclusion/exclusion criteria of OPAL-HK, 253 ZS treated and 243 patiromer treated patients were included in the analysis. After matching, all baseline characteristics were balanced between the two treatments. The mean baseline [K+]of both sets of patients was 5.60 mmol/L, and, after 48 hours of treatment, the mean [K+] achieved by ZS treated patients was significantly lower than those treated with patiromer (4.60 vs. 5.15 mmol/L; difference = −0.55 mmol/L; p-value <0.01; Figure 1). As a sensitivity analyses, the exclusion criteria were varied and the results remained consistent.


After adjusting for baseline differences, at 48 hours after the initiation of treatment, patients treated with ZS had a statistically significantly lower mean [K+] than those treated with patiromer.