Sodium Zirconium Cyclosilicate

LOKELMA (sodium zirconium cyclosilicate) is a non-absorbed zirconium silicate that preferentially captures potassium in exchange for hydrogen and sodium. In vitro , LOKELMA has a high affinity for potassium ions, even in the presence of other cations such as calcium and magnesium.

• LOKELMA is indicated for the treatment of hyperkalemia in adults. Limitation of Use LOKELMA should not be used as an emergency treatment for life-threatening hyperkalemia because of its delayed onset of action [see Clinical Pharmacology (12.2) and Clinical Studies (14) ] .ICD-10: E87.5

• None. None.contraindicated

• Recommended starting dose is 10 g administered three times a day for up to 48 hours. ( 2.1 ) • For maintenance treatment, recommended dose is 10 g once daily. Adjust dose at one-week intervals as needed (by 5 g daily) to obtain desired serum potassium target range. ( 2.1 ) Patients on Chronic Hemodialysis • Recommended starting dose is 5 g once daily on non-dialysis days. ( 2.2 ) See full Prescribing Information for additional dosing instructions, as well as reconstitution and administration instructions for the oral suspension. 2.1 Recommended Dosage For initial treatment of hyperkalemia, the recommended dose of LOKELMA is 10 g administered three times a day for up to 48 hours. Administer LOKELMA orally as a suspension in water [see Dosage and Administration (2.3) ] . For continued treatment, the recommended dose is 10 g once daily. Monitor serum potassium and adjust the dose of LOKELMA based on the serum potassium level and desired target range. During maintenance treatment, up-titrate based on the serum potassium level at intervals of 1-week or longer and in increments of 5 g. Decrease the dose of LOKELMA or discontinue if the serum potassium is below the desired target range. The recommended maintenance dose range is from 5 g every other day to 15 g daily. 2.2 Dosage Adjustment for Patients on Chronic Hemodialysis For patients on chronic hemodialysis, administer LOKELMA only on non-dialysis days. The recommended starting dose is 5 g once daily on non-dialysis days.

• Gastrointestinal Adverse Events in Patients with Motility Disorders. ( 5.1 ) • Edema. ( 5.2 ) • Hypokalemia in patients on hemodialysis. ( 5.3 ) • LOKELMA has radio-opaque properties and, therefore, may give the appearance typical of an imaging agent during abdominal X-ray procedures. ( 5.4 ) 5.1 Gastrointestinal Adverse Events in Patients with Motility Disorders Avoid use of LOKELMA in patients with severe constipation, bowel obstruction or impaction, including abnormal post-operative bowel motility disorders, because LOKELMA has not been studied in patients with these conditions and may be ineffective and may worsen gastrointestinal conditions. 5.2 Edema Each 5 g dose of LOKELMA contains approximately 400 mg of sodium, but the extent of absorption by the patient is unknown. In clinical trials of LOKELMA in patients who were not on dialysis, edema was observed and was generally mild to moderate in severity and was more commonly seen in patients treated with 15 g once daily. Monitor for signs of edema, particularly in patients who should restrict their sodium intake or are prone to fluid overload (e.g., heart failure or renal disease). Advise patients to adjust dietary sodium, if appropriate. Increase the dose of diuretics as needed [see Adverse Reactions (6) ] .

The following adverse reactions are discussed in greater detail elsewhere in the label: • Edema [see Warnings and Precautions (5.2) ] . Most common adverse reactions with LOKELMA: mild to moderate edema. ( 6.1 ) To report SUSPECTED ADVERSE REACTIONS, contact AstraZeneca at 1-800-236-9933 or FDA at 1-800-FDA-1088 or www.fda.gov/medwatch. 6.1 Clinical Studies Experience Because clinical studies are conducted under widely varying conditions, adverse reaction rates observed in the clinical studies of a drug cannot be directly compared to rates in the clinical studies of another drug and may not reflect the rates observed in practice. The total exposure to LOKELMA in the safety and efficacy clinical trials of patients not on dialysis with hyperkalemia was 1,760 patients with 652 patients exposed to LOKELMA for at least 6 months and 507 patients exposed for at least one year. The population (n=1,009) in the placebo-controlled trials included patients aged 22 to 96 years, females (n=454), Caucasians (n=859) and Blacks (n=130). Patients had hyperkalemia in association with comorbid diseases such as chronic kidney disease, heart failure, and diabetes mellitus. In placebo-controlled trials in which patients who were not on dialysis were treated with once daily doses of LOKELMA for up to 28 days, edema was reported in 4.4% of patients receiving 5 g, 5.9% of patients receiving 10 g and 16.1% of patients receiving 15 g LOKELMA compared to 2.4% of patients receiving placebo.

8.1 Pregnancy Risk Summary LOKELMA is not absorbed systemically following oral administration and maternal use is not expected to result in fetal exposure to the drug. 8.2 Lactation Risk Summary LOKELMA is not absorbed systemically following oral administration, and breastfeeding is not expected to result in exposure of the child to LOKELMA. 8.4 Pediatric Use Safety and effectiveness in pediatric patients have not been established. 8.5 Geriatric Use Of the total number of subjects in clinical studies of LOKELMA, 58% were age 65 and over, while 25% were 75 and over. No overall differences in safety or effectiveness were observed between these patients and younger patients.

Metabolism

LOKELMA is an inorganic, insoluble compound that is not subject to enzymatic metabolism. In a clinical study in patients with hyperkalemia in which zirconium concentrations were measured in the urine and blood, zirconium concentrations were similar in treated and untreated patients (i.e., either undetectable or around the lower limit of quantification of the assay).

• May 18, 2018NDANDA207078Astrazeneca

1. 1Death1,01130%
2. 2Blood Potassium Increased1775.2%
3. 3Diarrhoea1484.3%
4. 4Hyperkalaemia1364.0%
5. 5Constipation1133.3%
6. 6Off Label Use1133.3%
7. 7Cardiac Failure842.5%
8. 8Nausea822.4%
9. 9Acute Kidney Injury762.2%
10. 10Renal Failure752.2%
11. 11Drug Ineffective722.1%
12. 12Vomiting722.1%
13. 13Hypokalaemia702.0%
14. 14Chronic Kidney Disease682.0%
15. 15Oedema661.9%

The 10 most recently updated of 40 ClinicalTrials.gov registrations naming Sodium Zirconium Cyclosilicate as an intervention. Registration is not evidence of efficacy or safety — reference crosswalk only.

• VITALIZE.Use and Effectiveness of Sodium Zirconium Cyclosilicate (LokelmaTM) in the Real-world Setting in Spain
  Completed · Observational · 232 enrolled · AstraZeneca
  NCT06635499updated 2026-05-22
• An Open-label Study to Assess Safety and Efficacy of SZC in Paediatric Patients With Hyperkalaemia
  Recruiting · Phase 3 · Interventional · 140 enrolled · AstraZeneca
  NCT03813407updated 2026-05-15
• OPtimizing Aldosterone Receptor Antagonist Therapy by Sodium Zirconium Cyclosili-cate in Heart Failure -Extension (OPRA-HF Extension)
  Not yet recruiting · Phase 2 · Interventional · 110 enrolled · Sahlgrenska University Hospital
  NCT07576257updated 2026-05-08
• Lokelma for RAAS Maximisation in CKD & Heart Failure.
  Completed · Phase 3 · Interventional · 112 enrolled · St George's, University of London
  NCT05004363updated 2026-04-27
• Comparison of Potassium Binders in the ER
  Terminated · Phase 4 · Interventional · 37 enrolled · University of California, Irvine
  NCT04585542updated 2026-04-22
• A Clinical Trial to Define the Best Strategy for the Management of Heart Failure in Elderly Patients
  Recruiting · Phase 3 · Interventional · 94 enrolled · Fundación para la Investigación del Hospital Clínico de Valencia
  NCT06578078updated 2026-03-04
• Swedish Cardiac And Renal Failure Study-1
  Recruiting · Phase 2 · Interventional · 40 enrolled · Karolinska Institutet
  NCT07029503updated 2026-02-24
• A Study to Evaluate the Effect of Sodium Zirconium Cyclosilicate on Chronic Kidney Disease (CKD) Progression in Participants With CKD and Hyperkalaemia or at Risk of Hyperkalaemia
  Terminated · Phase 3 · Interventional · 1,112 enrolled · AstraZeneca
  NCT05056727updated 2026-01-08
• A National, Multicenter, Prospective, Observational Study to Assess Patient Characteristics, Treatment Algorithms and Disease Management of Hyperkalaemia Patients With Chronic Kidney Disease or Under Dialysis or With Heart Failure, Treated With Sodium Zirconium Cyclosilicate in Greece
  Completed · Observational · 125 enrolled · AstraZeneca
  NCT06185660updated 2025-12-30
• Continuing Sodium Zirconium Cyclosilicate (SZC) After Discharge Study
  Completed · Phase 4 · Interventional · 186 enrolled · AstraZeneca
  NCT05347693updated 2025-11-28

Frequently asked questions

How does Sodium Zirconium Cyclosilicate work?

LOKELMA (sodium zirconium cyclosilicate) is a non-absorbed zirconium silicate that preferentially captures potassium in exchange for hydrogen and sodium. In vitro , LOKELMA has a high affinity for potassium ions, even in the presence of other cations such as calcium and magnesium.

What is Sodium Zirconium Cyclosilicate used for?

According to FDA labeling, Sodium Zirconium Cyclosilicate carries indications including: LOKELMA is indicated for the treatment of hyperkalemia in adults. Limitation of Use LOKELMA should not be used as an emergency treatment for life-threatening hyperkalemia because of its delayed onset of action [see Clinical Pharmacology (12.2) and Clinical Studies (14) ] .. This is a reference summary of labeled uses, not medical advice or a treatment recommendation.

What class of drug is Sodium Zirconium Cyclosilicate?

Sodium Zirconium Cyclosilicate is classified as Drugs for treatment of hyperkalemia and hyperphosphatemia, Acidifying Activity, Electrolyte Activity, Digestive/GI System Activity Alteration.

What are the brand names for Sodium Zirconium Cyclosilicate?

Sodium Zirconium Cyclosilicate is marketed under brand names including Lokelma.

What are the contraindications for Sodium Zirconium Cyclosilicate?

Sodium Zirconium Cyclosilicate labeling lists contraindications including: None. None.. Always consult the full prescribing information and a clinician.