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Completed

NCT Number: NCT01493024

Safety & Efficacy of Zirconium Silicate in Chronic Kidney Disease or Moderate Kidney Dysfunction With Mild Hyperkalemia

It is hypothesized that zirconium silicate is safe and well tolerated and more effective than placebo (alternative hypothesis) in lowering serum potassium levels in subjects with serum potassium between 5 - 6.0 mmol/l versus no difference between zirconium silicate and placebo (null hypothesis). It is hypothesized that zirconium silicate even up to the top dose of 10g three times a day is well tolerated.

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Key information

Conditions

Hyperkalemia Chronic Disease Chronic Kidney Disease Disease Attributes Female Urogenital Diseases Female Urogenital Diseases and Pregnancy Complications Kidney Diseases Kidney Dysfunction Male Urogenital Diseases Metabolic Diseases Nutritional and Metabolic Diseases Pathologic Processes Pathological Conditions, Signs and Symptoms Renal Insufficiency Renal Insufficiency, Chronic Urogenital Diseases Urologic Diseases Water-Electrolyte Imbalance

Age range

18 year and older

Sex eligibility

All sexes

Study type

Interventional

Phase

Phase 2

Primary location

Southwest Clinical Research Institute, Tempe, Arizona, United States

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About this study

A total of 90 subjects with moderate CKD (defined as GFR between 40- 60ml/min) and mild hyperkalemia (S-K between 5-6 mmol/l) will be enrolled in the study where, in a double-blind dose-escalating fashion (three separate cohorts), they will be randomized to receive one of the doses of ZS (0.3g, 3g and 10g) or placebo, administered 3 times (tid) daily with meals. The first cohort will have 18 subjects while both of the second and third cohorts will have 36 subjects for a total of 90 subjects.

Safety and tolerability will be assessed by an Independent Data Safety Monitoring Board (DSMB) after completion of each cohort, before escalation to the next dose level will be allowed. The next dose escalation will happen no sooner than one week after the last dose of study drug at the previous dosing level has been administered. Safety stopping rules will be specified for this study. Within the first dose level (300 mg dose), 12 subjects will be randomized to receive ZS, whereas 6 subjects will be randomized to receive placebo for a total of 18 subjects in this first cohort. In the next two cohorts (3 g and 10 g doses), 24 subjects per cohort will be randomized to receive ZS, whereas 12 subjects per cohort will be randomized to receive placebo for a total of 36 subjects in each of the second and third cohorts.

Who can participate

Healthy volunteers accepted: No

Only the study team can determine whether someone qualifies for participation.

Inclusion criteria

  • Provision of written informed consent.
  • Over 18 years of age.
  • GFR between 40-60 ml/min as estimated by the CKD-EPI equation. After screening two additional GFR values of between 40-60ml/min must be repeated within 24 hours before inclusion is allowed.
  • S-K between 5.0 - 6.0 mmol/l (inclusive) during Study Day 0.
  • Ability to have repeated blood draws or effective venous catheterization.
  • Women of child bearing potential must be practicing a highly effective method of birth control.

Exclusion criteria

  • Pseudohyperkalemia such as excessive fist clinching hemolyzed blood specimen, severe leukocytosis or thrombocytosis.
  • Subjects treated with lactulose, xifaxan or other non-absorbed antibiotics for hyperammonemia within the last 7 days.
  • Subjects treated with resins (such as sevelamer acetate, calcium acetate or calcium carbonate, lanthanum carbonate, Sodium polystyrene sulfonate (SPS; e.g. Kayexalate®) within the last 7 days.
  • Subjects with a life expectancy of less than 3 months.
  • Subjects who are HIV positive.
  • Subjects 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.
  • Women who are pregnant, lactating, or planning to become pregnant.
  • Subjects with Ketoacidosis/Acidemia.
  • Cancer within the last 5 years (other than successfully treated basal or squamous cell carcinoma of the skin, carcinoma in situ of the cervix or early stage prostate cancer).
  • Presence of any condition which, in the opinion of the investigator, places the subject at undue risk or potentially jeopardizes the quality of the data to be generated.
  • Known hypersensitivity or previous anaphylaxis to Zirconium Silicate or to components thereof.
  • Subjects who have cardiac arrhythmias that require immediate treatment.
  • Subjects with ECG changes associated with hyperkalemia.
  • Subjects with acute kidney injury.

Treatment and study plan

Zirconium silicate (ZS)

Drug

Randomized escalating doses (0.3g, 3g and 10g) of ZS (fractionated, protonated microporous Zirconium Silicate, an oral sorbent) administered 3 times daily (tid) with meals.

Other names: ZS-9

Placebo

Drug

Randomized to mimic escalating doses of experimental drug administered 3 times daily (tid) with meals.

Other names: silicified microcrystalline cellulose

Primary outcomes

  1. Difference in the Exponential Rate of Change in Serum Potassium (S-K) Levels Versus Placebo During the Initial 48 Hours of Study Drug Treatment

    Time frame: 24 and 48 hours post first study drug dose

    The rate of fall in S-K levels during the initial 48 hours of study drug treatment between the placebo treated subjects and the ZS treated subjects measured on a log scale

Secondary outcomes

  1. Serum Potassium (S-K) at Individual Time Points.

    Time frame: First 48 hours of study

    Serum potassium (S-K) at individual time points through Study day 3/0hour.

  2. Time Specific S-K Levels to Normalization

    Time frame: 48 and 72 hours post first study drug dose

    Percent of subjects achieving S-K normalization (<=as defined by S-K levels of 3.5 to 4.9 mmol/L) from baseline at Study Days 2 and 3 at 0 hr.

  3. Time Specific Decreases in S-K Levels of > = 0.5 mmol/L

    Time frame: 24 and 48 hours post first study drug dose

    Percentage of participants achieving a 0.5mmol/L drop from baseline at Study Days 2 and 3 at 0 hr.

  4. Percentage of Participants With Normal S-K Levels at End of Study Day 2

    Time frame: 48 hours post first study drug dose

    Percentage (%) of subjects who achieve S-K normalization at end of Study Day 2

  5. Urine Sodium Excretion

    Time frame: 24 and 48 hours post first study drug dose

    Urine sodium excretion compared between the combined placebo-treated controls and the ZS-treated subjects (measured throughout two 24-hour periods on Study Days 1 and 2).

  6. Urine Potassium Excretion

    Time frame: 24 and 48 hours post study drug dose

    Urine potassium excretion compared between the combined placebo-treated controls and the ZS-treated subjects (measured throughout two 24-hour periods on Study Days 1 and 2).

  7. Urea Nitrogen Excretion

    Time frame: 24 and 48 hours post study drug dose

    Urea nitrogen excretion compared between the combined placebo-treated controls and the ZS-treated subjects (measured throughout two 24-hour periods on Study Days 1 and 2).

  8. Blood Urea Nitrogen

    Time frame: 24 and 48 hours post study drug dose

    Blood urea nitrogen compared between the combined placebo-treated controls and the ZS-treated subjects (measured 24 & 48 hours post dose on Study Days 2 and 3).

  9. Serum Magnesium (S-Mg) Levels

    Time frame: 24 and 48 hours post study drug dose

    Serum magnesium compared between the combined placebo-treated controls and the ZS-treated subjects (measured at 24 & 48 hours post dose on Study Days 2 and 3).

  10. Serum Calcium (S-Ca) Levels

    Time frame: 24 and 48 hours post study drug dose

    Serum calcium compared between the combined placebo-treated controls and the ZS-treated subjects (measured at 24 & 48 hours post dose on Study Days 2 and 3).

  11. Serum Sodium (S-Na) Levels

    Time frame: 24 and 48 hours post study drug dose

    Serum sodium compared between the combined placebo-treated controls and the ZS-treated subjects (measured at 24 & 48 hours post dose on Study Days 2 and 3).

  12. Serum Bicarbonate (HCO3) Levels

    Time frame: 24 and 48 hours post study drug dose

    Serum bicarbonate compared between the combined placebo-treated controls and the ZS-treated subjects (measured at 24 & 48 hours post dose on Study Days 2 and 3).

  13. 24-hour Urinary Excretion of Potassium

    Time frame: 24 and 48 hours post study drug dose

    24-hour urinary excretion of potassium on Study Days 1 and Day 2

  14. 24-hour Urinary Excretion of Sodium

    Time frame: 48 hours

    24-hour urinary excretion of sodium on Study Days 1 and Day 2

  15. 24-hour Urinary Excretion of Urea Nitrogen

    Time frame: 48 hours

    24-hour urinary excretion of urea nitrogen on Study Days 1 and Day 2

  16. 24-hour Urinary Excretion of Creatinine

    Time frame: 48 hours

    24-hour urinary excretion of creatinine on Study Days 1 and Day 2

Sponsors and collaborators

Lead sponsor

ZS Pharma, Inc.

Industry

Registry information

Official study title

Multicenter, Prospective, Randomized, Placebo-Controlled, Double-blind Dose Escalating Study of Safety, Tolerability and Pharmacodynamics of Zirconium Silicate in Chronic Kidney Disease and Moderate Kidney Dysfunction With Mild Hyperkalemia

Important dates

Study start
2011
Primary completion
2012
Study completion
2012
First posted
Dec 15, 2011
Registry last updated
Jun 29, 2018

OpenTrials presents study information sourced from ClinicalTrials.gov. The official registry record should be consulted for the latest information.

View the official ClinicalTrials.gov record (opens in a new tab)

This listing is for discovery and informational purposes only. It is not medical advice, does not guarantee that a study is recruiting, and does not determine eligibility. Contact the study team and a qualified healthcare professional when considering participation.

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