A Phase 3 interventional study of Sodium Zirconium Cyclosilicate (SZC) and SZC Placebo in Hyperkalemia, sponsored by AstraZeneca. Terminated at 340 sites in 26 countries. Open to participants aged 18 Years to 130 Years. Per ClinicalTrials.gov, last updated 2025-06-18.
Sponsored by AstraZeneca · Phase 3, Interventional, and Treatment
The purpose of this study is to evaluate the effect of Sodium Zirconium Cyclosilicate (SZC) on arrhythmia-related cardiovascular outcomes in participants on chronic hemodialysis with recurrent hyperkalemia.
This is an international, multicenter, event-driven, randomized, double-blind, parallel group, placebo-controlled study, evaluating the utility of SZC versus placebo to reduce the incidence of sudden cardiac death (SCD), stroke, and arrhythmia-related hospitalizations, interventions, and emergency department (ED) visits in participants on chronic hemodialysis with recurrent hyperkalemia.
133 studies on the registry are indexed under Hyperkalemia; 25 are open to participants now.
This study's enrollment of 2,690 is above the median of 87 across 102 interventional studies indexed under Hyperkalemia.
Browse Hyperkalemia studies →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.
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.
Exclusion Criteria:
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.
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.
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
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).
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.
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
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.
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.
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.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Childbearing potential
Able to become pregnant: from the first period until menopause, unless permanently unable to through surgery (removal of the womb, or of both ovaries or both fallopian tubes).
Criteria for people of childbearing potential usually ask for a negative pregnancy test and for contraception during the study and for a time after it.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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).
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Clinically significant
Judged by the study doctor to matter for your health or for the study. It is a doctor’s decision, so ask the study team if you are unsure whether something counts.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
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.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Drug: Sodium Zirconium Cyclosilicate (SZC)
Drug: SZC Placebo
Powder for oral suspension in a sachet. A dose is titrated in 5 g increments during a period of 4 weeks from 5 g up to 15 g qd on non-dialysis days. Afterward, the dose is adjusted monthly (or more frequent based on clinical judgment) depending on the current potassium value as measured after the long interdialytic interval (LIDI).
Also known as: Lokelma TM
Powder for oral suspension in a sachet. A dose is titrated in 5 g increments during a period of 4 weeks from 5 g up to 15 g qd on non-dialysis days. Afterward, the dose is adjusted monthly (or more frequent based on clinical judgment) depending on the current potassium value as measured after the LIDI.
Incidence of the Composite of Cardiac Event Outcomes
Incidence of the composite endpoint of SCD, all stroke, or hospitalization/intervention/emergency department (ED) visit due to arrhythmias is analyzed based on Cox regression model with treatment and region as covariates. Patients with no events are censored at final clinical assessment, death, or disposition event.
Time frame: From Randomization (Visit 4) up to week 129 (Randomized Study Intervention Phase)
Normokalemia at 12 Months Post-randomization
Logistic regression analysis of whether a subject is Normokalemic (S-K of 4.0 - 5.5 mmol/L ) after the LIDI at the 12-month visit.
Time frame: Randomization to 12-Month Visit
Incidence of the Composite of Arrhythmia Related Events
Incidence of the composite endpoint of hospitalization, intervention, emergency department (ED) visit due to arrhythmias is analyzed based on Cox regression model with treatment and region as covariates. Patients with no events are censored at final clinical assessment, death, or disposition event.
Time frame: From Randomization (Visit 4) up to week 129 (Randomized Study Intervention Phase)
| Milestone | SZC (Active) | Placebo |
|---|---|---|
| Started | 1349 | 1341 |
| Completed | 0 | 0 |
| Not completed | 1349 | 1341 |
| Withdrew: Death | 123 | 115 |
| Withdrew: Lost to follow-up | 3 | 10 |
| Withdrew: Withdrawal by subject | 73 | 101 |
| Withdrew: Subcategories under "other" not reported. | 1150 | 1115 |
Incidence of the composite endpoint of SCD, all stroke, or hospitalization/intervention/emergency department (ED) visit due to arrhythmias is analyzed based on Cox regression model with treatment and region as covariates. Patients with no events are censored at final clinical assessment, death, or disposition event.
| Participants | SZC (Active) | Placebo |
|---|---|---|
| Incidence of the Composite of Cardiac Event Outcomes | 119 | 119 |
Logistic regression analysis of whether a subject is Normokalemic (S-K of 4.0 - 5.5 mmol/L ) after the LIDI at the 12-month visit.
| Participants with event | SZC (Active) | Placebo |
|---|---|---|
| Normokalemia at 12 Months Post-randomization | 495 | 293 |
Incidence of the composite endpoint of hospitalization, intervention, emergency department (ED) visit due to arrhythmias is analyzed based on Cox regression model with treatment and region as covariates. Patients with no events are censored at final clinical assessment, death, or disposition event.
| Participants | SZC (Active) | Placebo |
|---|---|---|
| Incidence of the Composite of Arrhythmia Related Events | 74 | 65 |
Collected over From Randomization (Visit 4) up to week 129 (Randomized Study Intervention Phase). Non-serious events are listed at a 3% frequency threshold.
| Group | Deaths | Serious | Other |
|---|---|---|---|
| SZC (Active) | 120/1,348 (8.9%) | 521/1,348 (38.6%) | 558/1,348 (41.4%) |
| Placebo | 113/1,338 (8.4%) | 503/1,338 (37.6%) | 616/1,338 (46%) |
| Event | SZC (Active) | Placebo |
|---|---|---|
| PneumoniaInfections and infestations | 61/1348 | 60/1338 |
| HyperkalaemiaMetabolism and nutrition disorders | 15/1348 | 39/1338 |
| SepsisInfections and infestations | 36/1348 | 20/1338 |
| Acute myocardial infarctionCardiac disorders | 26/1348 | 19/1338 |
| HypervolaemiaMetabolism and nutrition disorders | 22/1348 | 16/1338 |
| Arteriovenous fistula thrombosisInjury, poisoning and procedural complications | 16/1348 | 21/1338 |
| Covid-19 pneumoniaInfections and infestations | 21/1348 | 20/1338 |
| Covid-19Infections and infestations | 19/1348 | 16/1338 |
| Arteriovenous fistula site complicationInjury, poisoning and procedural complications | 11/1348 | 17/1338 |
| DeathGeneral disorders | 15/1348 | 12/1338 |
| Event | SZC (Active) | Placebo |
|---|---|---|
| HyperkalaemiaMetabolism and nutrition disorders | 125/1348 | 280/1338 |
| Covid-19Infections and infestations | 145/1348 | 122/1338 |
| DiarrhoeaGastrointestinal disorders | 98/1348 | 93/1338 |
| HypertensionVascular disorders | 80/1348 | 82/1338 |
| ConstipationGastrointestinal disorders | 76/1348 | 57/1338 |
| AnaemiaBlood and lymphatic system disorders | 64/1348 | 44/1338 |
| NauseaGastrointestinal disorders | 43/1348 | 59/1338 |
| Dialysis hypotensionVascular disorders | 55/1348 | 59/1338 |
| VomitingGastrointestinal disorders | 44/1348 | 54/1338 |
| ArthralgiaMusculoskeletal and connective tissue disorders | 49/1348 | 54/1338 |
| Age, Continuous(Years) | SZC (Active) | Placebo | Total |
|---|---|---|---|
| Mean | 55.8 ± 13.3 | 56.3 ± 13.6 | 56.1 ± 13.4 |
| Age, Customized(Participants) | SZC (Active) | Placebo | Total |
|---|---|---|---|
| 18 yr ≤ Age < 51 yr | 442 | 441 | 883 |
| 51 yr ≤ Age < 65 yr | 526 | 509 | 1035 |
| 65 yr ≤ Age < 85 yr | 373 | 378 | 751 |
| Age ≥ 85 yr | 8 | 13 | 21 |
| Sex: Female, Male(Participants) | SZC (Active) | Placebo | Total |
|---|---|---|---|
| Female | 498 | 517 | 1015 |
| Male | 851 | 824 | 1675 |
| Race/Ethnicity, Customized(Participants) | SZC (Active) | Placebo | Total |
|---|---|---|---|
| AMERICAN INDIAN OR ALASKA NATIVE | 49 | 52 | 101 |
| ASIAN | 392 | 389 | 781 |
| BLACK OR AFRICAN AMERICAN | 121 | 130 | 251 |
| NATIVE HAWAIIAN OR OTHER PACIFIC ISLANDER | 3 | 2 | 5 |
| WHITE | 688 | 672 | 1360 |
| OTHER | 75 | 86 | 161 |
| NOT REPORTED | 21 | 10 | 31 |
| spKt/V(Dimensionless) | SZC (Active) | Placebo | Total |
|---|---|---|---|
| Mean | 1.48 ± 0.39 | 1.51 ± 0.47 | 1.49 ± 0.43 |
| Dialysis vintage(Years) | SZC (Active) | Placebo | Total |
|---|---|---|---|
| Mean | 6.01 ± 5.41 | 5.82 ± 5.20 | 5.92 ± 5.31 |
Showing the first 100 of 340 sites across 26 countries. Choose a country and city above to see the rest.
PDFs hosted by the registry, ClinicalTrials.gov.
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
Ran from Apr 2021 to primary completion in Mar 2024, 34 months.
Results were first posted in Jun 2025, 1 year 3 months after primary completion.
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This study is terminated, as verified in Jun 2025. You cannot join it, but the record below documents what was studied.
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Studies of the drug tested here: Sodium zirconium cyclosilicate