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Safety and Efficacy of Sodium Polystyrene Sulfonate in Hyperkalemia

This study has been terminated.
(Risk/benefit determination showed study revealed negative safety issues.)
Information provided by (Responsible Party):
ZS Pharma, Inc. Identifier:
First received: May 28, 2013
Last updated: August 29, 2014
Last verified: August 2014
It is hypothesized that SPS is more effective than placebo control (alternative hypothesis) in lowering i-STAT potassium levels in subjects with i-STAT potassium levels between 5.0 - 6.5 mmol/l versus no difference between SPS and placebo control (null hypothesis).

Condition Intervention Phase
Drug: Sodium polystyrene sulfonate
Drug: Silicified microcrystalline cellulose
Phase 4

Study Type: Interventional
Study Design: Allocation: Randomized
Intervention Model: Parallel Assignment
Masking: Double Blind (Participant, Care Provider, Investigator)
Primary Purpose: Supportive Care
Official Title: A Phase 4, Single-center, Prospective, Double-blind, Placebo-controlled, Randomized Study to Investigate the Safety and Efficacy of Sodium Polystyrene Sulfonate (SPS) in Subjects With Hyperkalemia.

Resource links provided by NLM:

Further study details as provided by ZS Pharma, Inc.:

Primary Outcome Measures:
  • Change in Serum Potassium Levels From Baseline After Administration of Sodium Polystyrene Sulfonate (SPS) Three Times a Day Without Co-administration of Sorbitol; Determine Incidence of Adverse Events. [ Time Frame: First 48 hours ]
    To perform a controlled evaluation of the safety and efficacy of 15g of SPS administered 3 times daily for 48 hours (6 doses) in patients with hyperkalemia (serum potassium levels between 5.0 - 6.5 mmol/l) at baseline.

Secondary Outcome Measures:
  • Change in Serum Sodium, Magnesium, Calcium Levels From Baseline After Administration of SPS. [ Time Frame: First 48 hours ]

Enrollment: 32
Study Start Date: May 2013
Study Completion Date: August 2013
Primary Completion Date: July 2013 (Final data collection date for primary outcome measure)
Arms Assigned Interventions
Active Comparator: Sodium Polystyrene Sulfonate
Oral suspension in water of 15g sodium polystyrene sulfonate administered three times (tid) daily for 48 hours without co-administration of Sorbitol.
Drug: Sodium polystyrene sulfonate
Oral suspension in water of 15g sodium polystyrene sulfonate administered three times (tid) daily for 48 hours without co-administration of Sorbitol.
Other Name: SPS
Placebo Comparator: Silicified microcrystalline cellulose
Oral suspension of placebo blended with pigment to have the same appearance, taste, odor and mode of administration as SPS.
Drug: Silicified microcrystalline cellulose
Oral suspension in water of placebo administered three times (tid) daily for 48 hours.
Other Name: Placebo

Detailed Description:

Subjects with mild to moderate hyperkalemia (i-STAT potassium levels between 5.0-6.5 mmol/l, inclusive) will be randomized 1:1 in a double-blind fashion to receive placebo or SPS (15g), administered tid with meals for 48 hours. Subjects will come back to the clinic on Study Day 9 for an End of Study (EOS) visit. Adverse experiences will be recorded.

Blood potassium levels will be evaluated by both i-STAT and the Local Laboratory prior to the first dose on Study Days 1 and 2, 1, 2, and 4 hours after the first dose on Study Day 1, 1 and 4 hours after the first dose on Study Day 2 and prior to breakfast on Study Day 3, after 48 hours of treatment.

Subjects who have i-STAT potassium levels > 6.5 mmol/l on Study Day 1 at the 4 hour post Dose 1 time point will be withdrawn from the study and will receive standard of care. If the i-STAT potassium value is between 6.1 and 6.5 mmol/l at the 4-hour post Dose 1 draw, subjects will be kept in the clinic for another 90 minutes post Dose 2 and another blood draw will be taken and an ECG will be performed. If the i-STAT potassium level is ≥ 6.2 mmol/l at this time point, the subject will be discontinued from the study and standard of care will be instituted. If the i-STAT potassium level is < 6.2 mmol/l, and the ECG does not show any of the ECG withdrawal criteria (see below), the subject will continue in the study.


Ages Eligible for Study:   18 Years and older   (Adult, Senior)
Sexes Eligible for Study:   All
Accepts Healthy Volunteers:   No

Inclusion Criteria:

  • Provision of written informed consent.
  • Over 18 years of age.
  • Mean i-STAT potassium values between 5.0 - 6.5 mmol/l inclusive, at screening (Study Day 0).
  • Previous participation in Clinical ZS-002 or ZS-003 protocol(s). However, subjects cannot be enrolled in this study until at least 30 days have elapsed from their last dose in study ZS-003.
  • Ability to have repeated blood draws or effective venous catheterization.
  • Women of childbearing potential must be using two forms of medically acceptable contraception (at least one barrier method) and have a negative pregnancy test at screening.

Women who are surgically sterile or those who are post-menopausal for at least 2 years are not considered to be of child-bearing potential.

Exclusion Criteria:

  • Pseudohyperkalemia signs and symptoms, such as excessive fist clenching 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, calcium carbonate, or lanthanum carbonate, within the last 7 days.
  • Subjects treated with Sodium Polystyrene Sulfonate (SPS; e.g. Kayexalate®) or ZS (microporous, fractionated, protonated zirconium silicate) within the last 30 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 diabetic ketoacidosis.
  • 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 ZS or to components thereof.
  • Previous treatment with SPS.
  • Treatment with a drug or device within the last 30 days that has not received regulatory approval at the time of study entry.
  • Subjects with cardiac arrhythmias that require immediate treatment.
  • Subjects on insulin where a stable dose has not yet been established.*
  • Subjects on dialysis. * Subjects on stable insulin or insulin analogues can be enrolled. Subjects who have been on the same insulin dose and regimen for > 14 days are considered stable. Whenever possible, all blood draws collected prior to meals should be collected prior to insulin/insulin analogue treatment.
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Please refer to this study by its identifier: NCT01866709

United States, Florida
Riverside Clinical Research
Edgewater, Florida, United States, 32132
Sponsors and Collaborators
ZS Pharma, Inc.
Study Chair: Henrik Rasmussen, MD ZS Pharma, Inc.
  More Information

Responsible Party: ZS Pharma, Inc. Identifier: NCT01866709     History of Changes
Other Study ID Numbers: SPS-001
Study First Received: May 28, 2013
Results First Received: August 20, 2014
Last Updated: August 29, 2014

Additional relevant MeSH terms:
Water-Electrolyte Imbalance
Metabolic Diseases
Polystyrene sulfonic acid
Chelating Agents
Sequestering Agents
Molecular Mechanisms of Pharmacological Action processed this record on May 25, 2017