ClinicalTrials.gg
CompletedNCT03528681HARMONIZE AsiaUpdated May 14, 2025Results posted

A Study to Investigate the Safety and Efficacy of ZS in Patients With Hyperkalemia.

A Phase 3 interventional study of Sodium Zirconium Cyclosilicate 5g and Sodium Zirconium Cyclosilicate 10g in Hyperkalemia, sponsored by AstraZeneca. Completed at 66 sites in 2 countries. Open to participants aged 18 Years to 90 Years. Per ClinicalTrials.gov, last updated 2025-05-14.

Sponsored by AstraZeneca · Phase 3, Interventional, and Treatment

Phase
Phase 3
Study type
Interventional
Enrollment
270
Allocation
Randomized
Ages
18 Years to 90 Years
Sex
All
01

Study summary

To evaluate the efficacy of two different doses (5 and 10 g) of ZS orally administered once daily (qd) vs placebo in maintaining normokalemia in initially hyperkalemic patients having achieved normokalemia following 24 or 48 hours of initial ZS therapy (10g TID).

Read the detailed description

This study will be conducted in approximately 35 centers in China. Before patients are randomized to the double-blind phase, they will receive open-label ZS for 24 or 48 hours during the initial phase. It is expected that approximately 490 patients will need to be enrolled, to have approximately 280 patients entered into the open-label initial phase resulting in 250 patients being randomized in the 28-day treatment study phase. Enrolment will be stopped when 250 patients have been initiated with the 28-day randomized treatment study phase.

02

Conditions studied

  • Hyperkalemia

Browse trials for

03

In context

Hyperkalemia

133 studies on the registry are indexed under Hyperkalemia; 25 are open to participants now.

This study's enrollment of 270 is above the median of 87 across 102 interventional studies indexed under Hyperkalemia.

Browse Hyperkalemia studies →

Lead sponsor

AstraZeneca is the lead sponsor of 3,499 studies on the registry; 270 are open to participants now.

Of its 368 completed or terminated interventional studies of FDA-regulated products, 178 (48%) have results posted.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 90 Years
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  1. Provision of (pre-screening consent) prior to any study specific procedures
  2. Female and male patients aged ≥18 and ≤ 90 years
  3. Provision of informed consent prior to any study specific procedures
  4. Two consecutive i-STAT potassium values, measured 60 minutes (± 10 minutes) apart, both ≥ 5.1 mmol/L and measured within 1 day of the first ZS dose on open-label initial phase Day 1
  5. Ability to have repeated blood draws or effective venous catheterization
  6. Female patients must be 1 year , surgically sterile, or using an acceptable method of for the duration of the study (from the time they sign consent) and for 3 months after the last dose of ZS/matching placebo to prevent pregnancy. In addition, oral contraceptives, approved contraceptive implant, long-term injectable contraception, intrauterine device, or tubal ligation are allowed. Oral contraception alone is not acceptable; additional barrier methods in conjunction with spermicide must be used

Exclusion criteria

Exclusion Criteria:

  1. Involvement in the planning and/or conduct of the study
  2. Participation in another clinical study with an product during the last 3 months
  3. Presence of any condition which, in the opinion of the investigator, places the patient at undue risk or potentially jeopardizes the quality of the data to be generated
  4. Pseudohyperkalemia signs and symptoms, such as hemolyzed blood specimen due to excessive fist clenching to make veins prominent, difficult or traumatic venepuncture, or history of severe leukocytosis or thrombocytosis
  5. Patients treated with lactulose, xifaxan (rifaximin) or other non-absorbed antibiotics for hyperammonemia within 7 days prior to the first dose of study drug
  6. Patients treated with resins,calcium acetate,calcium carbonate, or lanthanum carbonate,within 7 days prior to the first dose of study drug
  7. Patients with a of less than 3 months
  8. Patients who are severely physically or mentally incapacitated and who in the opinion of investigator are unable to perform the subjects' tasks associated with the protocol
  9. Female patients who are pregnant, lactating, or planning to become pregnant
  10. Patients with diabetic ketoacidosis
  11. Known or previous anaphylaxis to ZS or to components thereof
  12. Patients with cardiac arrhythmias that require immediate treatment
  13. History of associated with other medications that required discontinuation of that medication.
  14. Congenital long QT syndrome
  15. Symptomatic or uncontrolled atrial fibrillation despite treatment, or asymptomatic sustained ventricular tachycardia. Subjects with atrial fibrillation controlled by medication are permitted
  16. QTc(f) > 550 msec
  17. Patients on dialysis
  18. Patients who are blood donors should not donate blood during the study and for 3 months following their last dose of ZS
  19. Patients who need hospitalization after taking blood samples on day 1 of the open-label initial phase
Terms in these criteria, in plain language(7)

Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.

Informed consent

Before you join, the study team explains what taking part involves — its purpose, what happens, the risks and possible benefits — and answers your questions, so you can decide freely. Consent is usually recorded on a form (the informed consent form, ICF) signed by you or, where the law allows, by someone legally authorised to decide for you.

You can keep asking questions during the study, you are told of new information that matters, and you can choose to leave at any time.

Postmenopausal

Periods have stopped for good: usually no period for 12 months in a row without another medical reason, sometimes confirmed by a blood test (FSH).

Contraception

Ways of preventing pregnancy. “Highly effective” methods fail less than 1% of the time a year when used correctly — for example an IUD or an implant.

Criteria usually say which methods count and how long to keep using them after the last dose, sometimes for male participants too. Some studies accept a partner’s vasectomy if it was confirmed successful and that person is the participant’s only sexual partner.

Investigational drug or device

A drug or device being studied in a clinical trial.

It may be new, or already approved and being studied for another use, dose or form. Criteria often leave out people who took part in another study of one within a recent period, commonly 30 days or five half-lives.

Life expectancy

The study doctor’s estimate of how long someone is likely to live. Criteria use it so that people can stay in the study long enough for it to answer its question.

Hypersensitivity

An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.

QT and QTc

On an ECG, the QT interval is the time the heart’s lower chambers take to activate electrically and recover in each beat. QTc is that time adjusted for heart rate (QTcF by Fridericia’s formula, QTcB by Bazett’s). Some medicines lengthen it, and a long QTc can raise the risk of a dangerous heart rhythm.

The study may name a correction formula and a limit in milliseconds, often around 450–480.

05

Study design

Phase
Phase 3
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
Double (Participant, Investigator)
Enrollment
270 participants (actual)

Study arms

  • Experimental
    Sodium Zirconium Cyclosilicate 10g

    Suspension administered 10g orally once daily for 28 days after the open label initial phase.

    Drug: Sodium Zirconium Cyclosilicate 10g

  • Experimental
    Sodium Zirconium Cyclosilicate 5g

    Suspension administered 5g orally once daily for 28 days after the open label initial phase.

    Drug: Sodium Zirconium Cyclosilicate 5g

  • Placebo comparator
    Matching Placebo

    Suspension administered orally placebo once daily for 28 days after the open label initial phase.

    Drug: Placebo

Interventions

  • Suspension administered Sodium Zirconium Cyclosilicate 5g orally once daily for 28 days after the open label initial phase with suspension administered Sodium Zirconium Cyclosilicate 10g orally three times per day for at most 2 days.

  • Suspension administered Sodium Zirconium Cyclosilicate 10g orally once daily for 28 days after the open label initial phase with suspension administered Sodium Zirconium Cyclosilicate 10g orally three times per day for at most 2 days.

  • DrugPlacebo

    Suspension administered orally placebo once daily for 28 days after the open label initial phase with suspension administered Sodium Zirconium Cyclosilicate 10g orally three times per day for at most 2 days.

06

What researchers measure

Primary outcomes

  1. Least Square Mean S-K Level on Days 8-29

    Comparison between placebo and each SZC treatment group (high to low) with regard to the mean S-K level during the randomized treatment phase days 8-29. Mixed-effects models were used to estimate least-squares means.

    Time frame: Days 8 to 29 (Randomized treatment study phase) used for model-based least squares mean computation

Secondary outcomes

  1. Percentage of Patients Who Achieve Normokalemia

    Percentage of patients who achieve normokalemia during the open label initial phase at 24 hours and at the end of the open label phase. End of OLP is defined as Day 2 (24 hours post first dose) or Day 3 (48 hours post first dose) depending on when the subject achieved normokalemia based on the pre-dose i-STAT potassium level. The results in the table below are presented for OLP.

    Time frame: Through open label initial phase

  2. Exponential Rate of Change in S-K Levels

    Exponential rate of change in S-K levels (blood) during the open-label initial phase 24 hours post-dose. Least Square Mean corresponds to the exponential rate of change i.e. the slope (for time) in terms of log-transformed S-K levels. The results in the table below are presented for OLP.

    Time frame: Through 24 hours post-dose in the initial phase

  3. Absolute Change From Baseline in S-K Levels

    Absolute change from baseline in S-K levels at all measured time intervals. End of OLP is defined as Day 2 (24 hours post first dose) or Day 3 (48 hours post first dose) depending on when the subject achieved normokalemia based on the pre-dose i-STAT potassium level. The results in the table below are presented for OLP.

    Time frame: Through open label initial phase

  4. Percentage Change From Baseline in S-K Levels

    Percentage change from baseline in S-K levels at all measured time intervals. End of OLP is defined as Day 2 (24 hours post first dose) or Day 3 (48 hours post first dose) depending on when the subject achieved normokalemia based on the pre-dose i-STAT potassium level. The results in the table below are presented for OLP.

    Time frame: Through open label initial phase

  5. Proportion of Patients Who Remain Normokalemic During RTP

    Proportion of patients who remain normokalemic (as defined by S-K between 3.5-5.0 mmol/l, inclusive) during RTP (Day 8 to Day 29). The results in the table below are presented for RTP.

    Time frame: Through 28-day randomized treatment study phase day 8-29

  6. Proportion of Normokalemic Patients at the End of RTP

    Proportion of normokalemic patients (as defined by S-K between 3.5-5.0 mmol/l, inclusive). The results in the table below are presented for RTP.

    Time frame: The end of 28-day randomized treatment study phase

  7. Days Patients Remain Normokalemic

    The number of days patients remain normokalemic during days 8-29 of the randomized treatment study phase. The results in the table below are presented for RTP.

    Time frame: Through days 8-29 of the randomized treatment phase.

  8. Mean Change in S-K Levels

    The mean change in S-K levels evaluated relative to the RTP baseline. The results in the table below are presented for RTP.

    Time frame: Through 28-day randomized treatment phase.

  9. Mean Percent Change in S-K Levels

    The mean percent change in S-K levels evaluated relative to the RTP baseline. The results in the table below are presented for RTP.

    Time frame: Through 28-day randomized treatment phase.

  10. Least Square Mean Changes in S-Aldo and P-Renin Levels

    Comparison between placebo and each SZC treatment group (high to low) with regard to the mean S-Aldo and P-Renin levels during the randomized treatment phase days 15-29.

    Time frame: Through 28 day randomized treatment study phase day 15-29

  11. Hyperkalaemia at Day 29

    The number of patients with hyperkalaemia at day 29. The results in the table below are presented for RTP.

    Time frame: Day 29

  12. Percentage of Patients Without Hyperkalemia

    Kaplan-Meier estimate at Day 29 of percentage of patients without hyperkalemia. The results in the table below are presented for RTP.

    Time frame: Day 29 of randomized treatment phase

07

Results

Posted May 14, 2025

Participant flow

The study was conducted in 35 sites in China.

Open-Label Phase
Participant flow — Open-Label Phase
MilestoneSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Started270000
Completed256000
Not completed14000
Withdrew: Physician decision2000
Withdrew: Withdrawal by subject8000
Withdrew: (not collected)4000
Randomized Treatment Phase
Participant flow — Randomized Treatment Phase
MilestoneSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Started010010050
Completed0818538
Not completed0191512
Withdrew: Lost to follow-up0010
Withdrew: Physician decision0512
Withdrew: Withdrawal by subject0741
Withdrew: (study specific withdrawal criteria)0334
Withdrew: (not collected)0465

Outcome measures

PrimaryLeast Square Mean S-K Level on Days 8-29

Comparison between placebo and each SZC treatment group (high to low) with regard to the mean S-K level during the randomized treatment phase days 8-29. Mixed-effects models were used to estimate least-squares means.

Time frame:
Days 8 to 29 (Randomized treatment study phase) used for model-based least squares mean computation
Reported as:
Least squares mean · mmol/L
Least Square Mean S-K Level on Days 8-29
mmol/LSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Least Square Mean S-K Level on Days 8-29—4.859 (4.709 to 5.014)4.440 (4.304 to 4.580)5.225 (5.055 to 5.400)
Statistical analysis
  • Sodium Zirconium Cyclosilicate (SZC) 5g QD vs Placebo · Mixed Models Analysis · p = <0.001 · Back-transformed mean difference: 0.930 · 95% CI 0.902 to 0.959
  • Sodium Zirconium Cyclosilicate (SZC) 10g QD vs Placebo · Mixed Models Analysis · p = <0.001 · Back-transformed mean difference: 0.850 · 95% CI 0.825 to 0.876
SecondaryPercentage of Patients Who Achieve Normokalemia

Percentage of patients who achieve normokalemia during the open label initial phase at 24 hours and at the end of the open label phase. End of OLP is defined as Day 2 (24 hours post first dose) or Day 3 (48 hours post first dose) depending on when the subject achieved normokalemia based on the pre-dose i-STAT potassium level. The results in the table below are presented for OLP.

Time frame:
Through open label initial phase
Reported as:
Count of participants · Participants
Percentage of Patients Who Achieve Normokalemia
ParticipantsSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Normokalemic at 24h180———
Normokalemic at End of OLP228———
SecondaryExponential Rate of Change in S-K Levels

Exponential rate of change in S-K levels (blood) during the open-label initial phase 24 hours post-dose. Least Square Mean corresponds to the exponential rate of change i.e. the slope (for time) in terms of log-transformed S-K levels. The results in the table below are presented for OLP.

Time frame:
Through 24 hours post-dose in the initial phase
Reported as:
Least squares mean · log(mmol/L)/h
Exponential Rate of Change in S-K Levels
log(mmol/L)/hSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Exponential Rate of Change in S-K Levels-0.0051 ± 0.00027———
SecondaryAbsolute Change From Baseline in S-K Levels

Absolute change from baseline in S-K levels at all measured time intervals. End of OLP is defined as Day 2 (24 hours post first dose) or Day 3 (48 hours post first dose) depending on when the subject achieved normokalemia based on the pre-dose i-STAT potassium level. The results in the table below are presented for OLP.

Time frame:
Through open label initial phase
Reported as:
Mean · mmol/L
Absolute Change From Baseline in S-K Levels
mmol/LSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
OLP - 24 hours-0.936 ± 0.377———
End of OLP-1.107 ± 0.466———
SecondaryPercentage Change From Baseline in S-K Levels

Percentage change from baseline in S-K levels at all measured time intervals. End of OLP is defined as Day 2 (24 hours post first dose) or Day 3 (48 hours post first dose) depending on when the subject achieved normokalemia based on the pre-dose i-STAT potassium level. The results in the table below are presented for OLP.

Time frame:
Through open label initial phase
Reported as:
Mean · Percentage
Percentage Change From Baseline in S-K Levels
PercentageSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
OLP - 24 hours-15.880 ± 5.980———
End of OLP-18.588 ± 6.701———
SecondaryProportion of Patients Who Remain Normokalemic During RTP

Proportion of patients who remain normokalemic (as defined by S-K between 3.5-5.0 mmol/l, inclusive) during RTP (Day 8 to Day 29). The results in the table below are presented for RTP.

Time frame:
Through 28-day randomized treatment study phase day 8-29
Reported as:
Number · Average probability
Proportion of Patients Who Remain Normokalemic During RTP
Average probabilitySodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Proportion of Patients Who Remain Normokalemic During RTP—0.5960.8180.279
Statistical analysis
  • Sodium Zirconium Cyclosilicate (SZC) 5g QD vs Placebo · Mixed Models Analysis · p = <0.001 · Odds ratio (or): 3.80 · 95% CI 2.17 to 6.67
  • Sodium Zirconium Cyclosilicate (SZC) 10g QD vs Placebo · Mixed Models Analysis · p = <0.001 · Odds ratio (or): 11.63 · 95% CI 6.45 to 21.00
SecondaryProportion of Normokalemic Patients at the End of RTP

Proportion of normokalemic patients (as defined by S-K between 3.5-5.0 mmol/l, inclusive). The results in the table below are presented for RTP.

Time frame:
The end of 28-day randomized treatment study phase
Reported as:
Count of participants · Participants
Proportion of Normokalemic Patients at the End of RTP
ParticipantsSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Proportion of Normokalemic Patients at the End of RTP—476514
Statistical analysis
  • Sodium Zirconium Cyclosilicate (SZC) 5g QD vs Placebo · Regression, Logistic · p = 0.035 · Odds ratio (or): 2.54 · 95% CI 1.07 to 6.05
  • Sodium Zirconium Cyclosilicate (SZC) 10g QD vs Placebo · Regression, Logistic · p = <0.001 · Odds ratio (or): 6.25 · 95% CI 2.56 to 15.27
SecondaryDays Patients Remain Normokalemic

The number of days patients remain normokalemic during days 8-29 of the randomized treatment study phase. The results in the table below are presented for RTP.

Time frame:
Through days 8-29 of the randomized treatment phase.
Reported as:
Least squares mean · Day
Days Patients Remain Normokalemic
DaySodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Days Patients Remain Normokalemic—9.11 ± 1.41314.54 ± 1.3973.40 ± 1.473
Statistical analysis
  • Sodium Zirconium Cyclosilicate (SZC) 5g QD vs Placebo · Regression, Linear · p = <0.001 · Median difference (final values): 5.72 · 95% CI 3.13 to 8.31
  • Sodium Zirconium Cyclosilicate (SZC) 10g QD vs Placebo · Regression, Linear · p = <0.001 · Mean difference (final values): 11.14 · 95% CI 8.57 to 13.71
SecondaryMean Change in S-K Levels

The mean change in S-K levels evaluated relative to the RTP baseline. The results in the table below are presented for RTP.

Time frame:
Through 28-day randomized treatment phase.
Reported as:
Mean · mmol/L
Mean Change in S-K Levels
mmol/LSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Day 2 change from RTP baseline—-0.04 ± 0.299-0.15 ± 0.3140.02 ± 0.315
Day 5 change from RTP baseline—0.09 ± 0.434-0.27 ± 0.4640.40 ± 0.423
Day 8 change from RTP baseline—0.20 ± 0.481-0.29 ± 0.5410.53 ± 0.485
Day 12 change from RTP baseline—0.25 ± 0.539-0.23 ± 0.5970.67 ± 0.452
Day 15 change from RTP baseline—0.26 ± 0.557-0.24 ± 0.5810.67 ± 0.494
Day 19 change from RTP baseline—0.41 ± 0.606-0.19 ± 0.6160.61 ± 0.506
Day 22 change from RTP baseline—0.32 ± 0.543-0.13 ± 0.5380.62 ± 0.536
Day 26 change from RTP baseline—0.22 ± 0.556-0.05 ± 0.6270.55 ± 0.447
Day 29 change from RTP baseline—0.23 ± 0.4940.01 ± 0.5780.47 ± 0.520
EOS change from RTP baseline—0.57 ± 0.4990.67 ± 0.6880.55 ± 0.667
SecondaryMean Percent Change in S-K Levels

The mean percent change in S-K levels evaluated relative to the RTP baseline. The results in the table below are presented for RTP.

Time frame:
Through 28-day randomized treatment phase.
Reported as:
Mean · Percent change
Mean Percent Change in S-K Levels
Percent changeSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Day 2 change from RTP baseline—-0.81 ± 6.308-3.13 ± 6.6270.41 ± 6.670
Day 5 change from RTP baseline—2.10 ± 9.009-5.57 ± 9.6888.56 ± 8.989
Day 8 change from RTP baseline—4.45 ± 10.260-6.05 ± 11.35211.24 ± 9.989
Day 12 change from RTP baseline—5.55 ± 11.564-4.65 ± 12.60414.39 ± 9.908
Day 15 change from RTP baseline—5.85 ± 11.840-4.85 ± 12.10714.50 ± 10.775
Day 19 change from RTP baseline—9.01 ± 13.285-3.76 ± 12.79713.34 ± 11.266
Day 22 change from RTP baseline—7.09 ± 11.952-2.59 ± 11.29213.15 ± 11.686
Day 26 change from RTP baseline—5.12 ± 12.130-0.76 ± 13.27811.95 ± 9.809
Day 29 change from RTP baseline—5.24 ± 10.9410.48 ± 12.14210.20 ± 11.438
EOS change from RTP baseline—12.42 ± 11.05414.47 ± 14.79711.74 ± 14.477
SecondaryLeast Square Mean Changes in S-Aldo and P-Renin Levels

Comparison between placebo and each SZC treatment group (high to low) with regard to the mean S-Aldo and P-Renin levels during the randomized treatment phase days 15-29.

Time frame:
Through 28 day randomized treatment study phase day 15-29
Reported as:
Least squares mean · pmol/L
Least Square Mean Changes in S-Aldo and P-Renin Levels
pmol/LSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
S-Aldo—-21.926 (-80.492 to 36.640)-53.945 (-112.189 to 4.300)83.322 (22.519 to 144.124)
P-Renin—-0.348 (-0.484 to -0.212)-0.424 (-0.559 to -0.288)-0.362 (-0.505 to -0.218)
Statistical analysis
  • Sodium Zirconium Cyclosilicate (SZC) 5g QD vs Placebo · Mixed Models Analysis · p = <0.001 · Mean difference (final values): -105.248 · 95% CI -161.293 to -49.203
  • Sodium Zirconium Cyclosilicate (SZC) 10g QD vs Placebo · Mixed Models Analysis · p = <0.001 · Median difference (final values): -137.267 · 95% CI -192.596 to -81.937
  • Sodium Zirconium Cyclosilicate (SZC) 5g QD vs Placebo · Mixed Models Analysis · p = 0.839 · Mean difference (final values): 0.014 · 95% CI -0.120 to 0.147
  • Sodium Zirconium Cyclosilicate (SZC) 10g QD vs Placebo · Mixed Models Analysis · p = 0.355 · Mean difference (final values): -0.062 · 95% CI -0.195 to 0.070
SecondaryHyperkalaemia at Day 29

The number of patients with hyperkalaemia at day 29. The results in the table below are presented for RTP.

Time frame:
Day 29
Reported as:
Count of participants · Participants
Hyperkalaemia at Day 29
ParticipantsSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Hyperkalaemia at Day 29—775048
SecondaryPercentage of Patients Without Hyperkalemia

Kaplan-Meier estimate at Day 29 of percentage of patients without hyperkalemia. The results in the table below are presented for RTP.

Time frame:
Day 29 of randomized treatment phase
Reported as:
Number · Percentage
Percentage of Patients Without Hyperkalemia
PercentageSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Percentage of Patients Without Hyperkalemia—20.3 (12.8 to 29.0)47.1 (36.5 to 57.0)4.0 (0.7 to 12.1)
Statistical analysis
  • Sodium Zirconium Cyclosilicate (SZC) 5g QD vs Placebo · Regression, Cox · p = <0.001 · Hazard ratio (hr): 0.39 · 95% CI 0.27 to 0.57
  • Sodium Zirconium Cyclosilicate (SZC) 10g QD vs Placebo · Regression, Cox · p = <0.001 · Hazard ratio (hr): 0.16 · 95% CI 0.10 to 0.25

Adverse events

Collected over Adverse Events were collected from the time of the main study informed consent (Day 1, Visit 3) throughout the treatment period and including the End of Study (EOS) visit. Serious Adverse Events were collected from the time of the optional Pre-screening informed consent (Visit 1) throughout the treatment period and including the EOS visit. Maximum duration of treatment was 8 days for open-label initial phase and 30 days for the randomized treatment phase.. Non-serious events are listed at a 0% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
Sodium Zirconium Cyclosilicate (SZC) 10g TID0/270 (0%)1/270 (0.4%)38/270 (14.1%)
Sodium Zirconium Cyclosilicate (SZC) 5g QD0/100 (0%)6/100 (6%)48/100 (48%)
Sodium Zirconium Cyclosilicate (SZC) 10g QD0/100 (0%)3/100 (3%)42/100 (42%)
Placebo0/50 (0%)1/50 (2%)17/50 (34%)
Most frequent serious events
Most frequent serious events
EventSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Abdominal pain upperGastrointestinal disorders0/2700/1000/1001/50
Upper gastrointestinal haemorrhageGastrointestinal disorders0/2701/1000/1000/50
OedemaGeneral disorders0/2700/1001/1000/50
Oedema peripheralGeneral disorders0/2701/1000/1000/50
HyperkalaemiaMetabolism and nutrition disorders1/2701/1001/1000/50
Chronic kidney diseaseRenal and urinary disorders0/2701/1000/1000/50
End stage renal diseaseRenal and urinary disorders0/2701/1001/1000/50
Sleep apnoea syndromeRespiratory, thoracic and mediastinal disorders0/2701/1000/1000/50
Most frequent other events
Showing 10 of 102
Most frequent other events
EventSodium Zirconium Cyclosilicate (SZC) 10g TIDSodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlacebo
Oedema peripheralGeneral disorders0/2708/10012/1000/50
HyperkalaemiaMetabolism and nutrition disorders0/2701/1001/1005/50
ConstipationGastrointestinal disorders3/2707/1005/1000/50
Upper respiratory tract infectionInfections and infestations2/2704/1004/1000/50
DizzinessNervous system disorders3/2704/1003/1002/50
DyspnoeaRespiratory, thoracic and mediastinal disorders0/2700/1002/1002/50
Eyelid oedemaEye disorders1/2700/1003/1000/50
DiarrhoeaGastrointestinal disorders4/2700/1003/1001/50
VomitingGastrointestinal disorders3/2701/1003/1000/50
Peripheral swellingGeneral disorders0/2700/1003/1000/50

Baseline characteristics

The study consisted of two phases, an Open-label initial phase (OLP) and a Randomized treatment phase (RTP). 270 participants entered OLP, out of these 250 entered RTP \& received Placebo, SZC 5g QD or SZC 10g QD in a 1:2:2 ratio.

Age, Continuous
Age, Continuous(Years)Sodium Zirconium Cyclosilicate (SZC)Sodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlaceboTotal
Randomized treatment phase (RTP)—54.3 ± 13.9255.6 ± 14.4759.7 ± 14.255.9 ± 14.28
Open-label initial phase (OLP)56.4 ± 14.17———56.4 ± 14.17
Sex: Female, Male
Sex: Female, Male(Participants)Sodium Zirconium Cyclosilicate (SZC)Sodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlaceboTotal
Randomized treatment phase (RTP) — Female—35401994
Randomized treatment phase (RTP) — Male—656031156
Open-label initial phase (OLP) — Female103———103
Open-label initial phase (OLP) — Male167———167
Race/Ethnicity, Customized
Race/Ethnicity, Customized(Participants)Sodium Zirconium Cyclosilicate (SZC)Sodium Zirconium Cyclosilicate (SZC) 5g QDSodium Zirconium Cyclosilicate (SZC) 10g QDPlaceboTotal
Not Hispanic or Latino Randomized treatment phase (RTP)—10010050250
Not Hispanic or Latino Open-label initial phase (OLP)270———270
08

Study locations

66 sites
  • Research Site
    Baotou, 14010, China
  • Research Site
    Beijing, 100029, China
  • Research Site
    Beijing, 100144, China
  • Research Site
    Beijing, 100853, China
  • Research Site
    Beijing, 102206, China
  • Research Site
    Bengbu, 233004, China
  • Research Site
    Changchun, 130021, China
  • Research Site
    Changsha, 410008, China
  • Research Site
    Changsha, 430033, China
  • Research Site
    Chengdu, 610041, China
  • Research Site
    Chengdu, 610072, China
  • Research Site
    Dalian, 116027, China
  • Research Site
    Dongguan, 523009, China
  • Research Site
    Fuzhou, 350005, China
  • Research Site
    Fuzhou, 350025, China
  • Research Site
    Guangzhou, 510080, China
  • Research Site
    Guangzhou, 510120, China
  • Research Site
    Guiyang, 550004, China
  • Research Site
    Haikou, 570311, China
  • Research Site
    Hangzhou, 310003, China
  • Research Site
    Hangzhou, 310009, China
  • Research Site
    Hefei, 230022, China
  • Research Site
    Hefei, 230601, China
  • Research Site
    Jilin, 132011, China
  • Research Site
    Jinan, 250021, China
  • Research Site
    Jingzhou, 434020, China
  • Research Site
    Kunming, 650011, China
  • Research Site
    Kunming, 650021, China
  • Research Site
    Lanzhou, 730030, China
  • Research Site
    Nanchang, 330006, China
  • Research Site
    Ningbo, 315010, China
  • Research Site
    Qingdao, 266000, China
  • Research Site
    Shanghai, 200025, China
  • Research Site
    Shanghai, 200090, China
  • Research Site
    Shanghai, 200127, China
  • Research Site
    Suzhou, 215006, China
  • Research Site
    Taiyuan, 030001, China
  • Research Site
    Taiyuan, 030012, China
  • Research Site
    Tianjin, 300121, China
  • Research Site
    Tianjin, 300211, China
  • Research Site
    Wuhan, 430030, China
  • Research Site
    Wuhan, 430070, China
  • Research Site
    Wuxi, 214023, China
  • Research Site
    Xiamen, 361003, China
  • Research Site
    Xian, 710061, China
  • Research Site
    Xining, 810001, China
  • Research Site
    Xining, 810007, China
  • Research Site
    Yangzhou, 225001, China
  • Research Site
    Yichang, 443003, China
  • Research Site
    Yinchuan, 750004, China
  • Research Site
    Zhanjiang, 524001, China
  • Research Site
    Zhuzhou, 412007, China
  • Research Site
    Ahmedabad, 380006, India
  • Research Site
    Ahmedabad, 380015, India
  • Research Site
    Ahmedabad, 380016, India
  • Research Site
    Bangalore, 560002, India
  • Research Site
    Bangalore, 560004, India
  • Research Site
    Bengaluru, 560004, India
  • Research Site
    Chandigarh, 160030, India
  • Research Site
    Chennai, 600001, India
  • Research Site
    Hyderabad, 500018, India
  • Research Site
    Kolkata, 700054, India
  • Research Site
    Nagpur, 440012, India
  • Research Site
    New Delhi, 110002, India
  • Research Site
    New Delhi, 110017, India
  • Research Site
    Vijayawada, 522002, India
09

References and documents

Study documents

PDFs hosted by the registry, ClinicalTrials.gov.

Individual participant data

Plan to share: Yes — Qualified researchers can request access to anonymized individual patient-level data from AstraZeneca group of companies sponsored clinical trials via the request portal. All request will be evaluated as per the AZ disclosure commitment: https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure. Yes, indicates that AZ are accepting requests for IPD, but this does not mean all requests will be shared.

Supporting information: Study protocol, Statistical analysis plan

Time frame: AstraZeneca will meet or exceed data availability as per the commitments made to the EFPIA Pharma Data Sharing Principles. For details of our timelines, please rerefer to our disclosure commitment at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure

Access criteria: When a request has been approved AstraZeneca will provide access to the de-identified individual patient-level data in an approved sponsored tool . Signed Data Sharing Agreement (non-negotiable contract for data accessors) must be in place before accessing requested information. Additionally, all users will need to accept the terms and conditions of the SAS MSE to gain access. For additional details, please review the Disclosure Statements at https://astrazenecagrouptrials.pharmacm.com/ST/Submission/Disclosure.

Data sharing details ↗ · astrazenecagroup-dt.pharmacm.com

10

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on May 14, 2025, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
11

Registry details

Key details

Study ID
NCT03528681
Lead sponsor
AstraZeneca
Responsible party
Sponsor
First posted
May 18, 2018
Start date
May 6, 2021
Primary completion
Sep 15, 2022
Completion
Sep 15, 2022
Results posted
May 14, 2025
Last update
May 14, 2025

Oversight

Data monitoring committee
No
FDA-regulated drug
No
FDA-regulated device
No
View the source record on ClinicalTrials.gov ↗

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Studies of the drug tested here: Sodium zirconium cyclosilicate

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