Conditions: ESRD Hyperkalemia End Stage Renal Disease
Keywords: End Stage Renal Disease ESRD Hyperkalemia
Allocation: NA | Intervention model: SEQUENTIAL
Enrollment: 27
Healthy volunteers: no

Brief summary:
The Effects of Patiromer on Serum Potassium Level and Gut Microbiome of ESRD Patients With Hyperkalemia (potassium greater than 5 milliequivalents per liter) is a non-randomized, crossover study. This is an open-label, pilot clinical trial with 3 sequential phases of (a) 2 weeks of no intervention, (b) 12 weeks of Patiromer treatment, and (c) 6 weeks of no intervention. Treatment with Patiromer will be initiated at a dose of 8.4 grams, once daily and observed for a week, then uptitrated to 16.8 grams once daily. Eligible study subjects will collect stool samples and provide blood and urine samples.

Detailed description:

Arms:
arm 1: This arm is a 2 week observation period before the start of the Patiromer treatment phase, followed by a 12 week treatment phase, and 6 week no treatment observation phase.

Pre-Treatment (Wk 1-2): Observational period. Baseline sample collection of blood and stool. No medication.

Treatment (Wk 3-14): Participants will take 8.4 grams of Patiromer once daily for one week, during which serum potassium and gastrointestinal symptoms will be evaluated. If tolerated and in the absence of hypokalemia, the dose will be up-titrated to 16.8 grams once daily for the remaining 11 weeks. Blood and stool will be collected.

Post-Treatment (Wk 15-20): Observational period. No medication. Blood and stool will be collected.

Interventions: intervention 1: Patiromer
Intervention descriptions: intervention 1: Patiromer will be orally self-administered by participants.

Protocol document:
Prot_SAP_000.pdf: 
Relypsa 
 
Protocol # R-01 
Clinical Study Protocol 
 
Version 1.4 
 
 
The effects of Patiromer on serum potassium level 
and gut microbiome of ESRD patients with 
hyperkalemia 
 
 
Protocol #: 
R-01 
Principal Investigator: 
Dominic Raj 
Version #: 
1.4 
Version Date: 
July 25, 2017 
 
 
 


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STATEMENT OF COMPLIANCE 
STUDY TITLE 
The effects of Patiromer on serum potassium level and gut 
microbiome of ESRD patients with hyperkalemia 
PROTOCOL NUMBER  
R-01 
PROTOCOL VERSION 
v1.4 
VERSION DATE 
July 01, 2017 
STUDY SPONSOR 
Relypsa 
DECLARATION OF THE INVESTIGATOR: 
The study will be conducted in accordance with the International Conference on 
Harmonization (ICH) document “Guidance for Industry – E6 Good Clinical Practice: 
Consolidated Guidance” dated April 1996 and the Code of Federal Regulations on the 
Protection of Human Subjects (45 CFR Part 46). The Principal Investigator will assure that no 
deviation from, or changes to the protocol will take place without prior agreement from the 
sponsor and documented approval from the Institutional Review Board (IRB), except where 
necessary to eliminate an immediate hazard(s) to the study subjects. All personnel involved 
in the conduct of this study have completed Human Subjects Protection Training.  
Further, I will conduct the study in keeping with local legal and regulatory requirements. 
NAME (Print): _____________________________________________ 
SIGNATURE: _____________________________________________ 
DATE: _____________________________________________ 
 
 
 


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PROTOCOL SYNOPSIS 
Study Title: 
The effects of Patiromer on serum potassium level and gut 
microbiome of ESRD patients with hyperkalemia 
Phase: 
Phase 2, safety and efficacy trial 
Primary Objective: 
To examine the tolerability, safety, and efficacy of Patiromer in 
lowering serum potassium levels in ESRD patients that are on 
maintenance dialysis with hyperkalemia (K>5.0 mEq/L). 
Secondary Objective: 
To assess the changes in gut microbiome and serum metabolom 
profiles of hyperkalemic ESRD patients treated with Patiromer. 
Study Design: 
This is a non-randomized, crossover study. 25 ESRD patients with 
hyperkalemia (K>5.0 mEQ/L) will be enrolled in an open-label, 
pilot clinical trial with 3 sequential phases of (a) 2 weeks of no 
intervention, (b) 12 weeks of Patiromer treatment, and (c) 6 weeks 
of no intervention. Treatment with Patiromer will be initiated at a 
dose of 8.4 gram, once daily and observed for a week, then 
uptitrated to 16.8 g once daily.  Eligible subjects will collect stool 
samples and provide blood and urine samples.  
Study Duration: 
The total anticipated study duration is approximately 2 years, with 
anticipated enrollment duration of 9 months, and anticipated 
study conduct duration upon full enrollment of 3 months. The 
remaining 12 month will needed for data analysis. 
Study Population 
The study will enroll approximately 25 adult male or female 
subjects between the ages of 18-85 years.  Subjects with diabetes 
or HIV will also be enrolled.  
Study Products: 
Patriomer is an FDA-approved orally administered drug used for 
the treatment of hyperkalemia. It is a non-absorbed polymer that 
binds potassium throughout the gastrointestinal tract and leads to 


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lowering serum potassium levels (1). Prior Patiromer clinical trials 
have demonstrated the drug’s utility in treating hyperkalemia in 
patients with diabetic kidney disease (1; 2).  
 


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Key Roles 
Principal Investigator 
(responsible 
for 
study 
conduct and all site-related 
medical decisions) 
Dominic Raj, MD 
2150 Pennsylvania Ave NW, Suite 3-438, Washington DC, 
20037 
Phone#: (202) 741-2283 
Email: draj@mfa.gwu.edu 
Clinical 
Laboratory 
and 
Laboratory Director 
Ali Ramezani, PhD 
Address: 2300 I St., NW, Rm 726, Washington DC, 20037 
 
 
 


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1 
Introduction: Background and Scientific Rationale 
1.1 
Background 
1.1.1 Gut Microbiota 
Human gut harbors a complex community of over 100 trillion microbial cells, which constitute 
the microbiota (3). The gut microbiome encodes about 3.3 million genes, which is 150 times 
that of our own genome (4). The symbiotic gut microbiota provides complementary biological 
and metabolic functions that cannot be performed by humans (5). Disruption to the normal 
balance between the gut microbiota and the host (dysbiosis) is associated with diverse disease 
states such as obesity, inflammatory bowel disease, neurological disorders, cancer, and 
cardiovascular disease (CVD) (6-11). 
Findings from the human microbiome project (HMP) revealed that the gut microbiome is highly 
specific, personalized and functionally relevant to health (12). Gut microbiota is altered in 
patients with chronic kidney disease (CKD). Preliminary evidence indicates that the dysbiotic 
gut microbiota could be the source for a plethora of uremic toxins (13), many of which have 
been shown to be positively correlated with progression of CKD and increased risk for major 
adverse cardiovascular events defined as death, myocardial infarction, or stroke (14-16). 
Therefore, correcting the gut microbiota dysbiosis might be a therapeutic option for reducing 
both the progression as well as the cardiovascular burden of CKD. 
Hyperkalemia, a frequent and serious electrolyte abnormality in patients with kidney failure, 
can lead to life threatening cardiac arrhythmias (17; 18). Even relatively mild (5.5 to 6.0 mEq/L) 
hyperkalemia is associated with an increased risk of mortality (19). Compensatory increase in 
fecal potassium excretion occurs in patients with renal failure (20; 21). Normally, the gut is 
responsible for only 5% of total potassium excretion; however, in patients with end-stage renal 
disease (ESRD), this can increase substantially to account for 30% to 50% of potassium 
excretion (22).  
Preliminary evidence indicates that the growth rate of certain bacteria is affected by the 
increasing concentration of potassium in the growth medium (23). E. coli populations exhibited 
higher growth rates in the presence of additional potassium (23). However, potassium may also 


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adversely affect the growth of commensal methanogens. At increased concentrations, 
potassium decreases methanogenesis by entering cells through membrane leaks or via a 
potassium transport carrier, thus decreasing the transmembrane electron potential (24). This 
has been shown to have a significant impact on the pH regulation of the bacteria (25).  
Patiromer for oral suspension is an FDA-approved orally administered drug used for the 
treatment of hyperkalemia. It is a nonabsorbed polymer that binds potassium throughout the 
gastrointestinal tract and leads to lowering serum potassium levels (1). Prior Patiromer clinical 
trials have demonstrated the drug’s utility in treating hyperkalemia in patients with diabetic 
kidney disease (1; 2). 
1.1.2 Rationale for Study and Study Design 
This study will add to the body of data and expand the knowledge about the tolerability, safety, 
and efficacy of Patiromer in lowering serum potassium levels in ESRD patients with 
hyperkalemia. Furthermore, the study will examine changes in gut microbiome and serum 
metabolome profiles of hyperkalemic ESRD patients treated with Patiromer in order to 
determine the impact of lowering gut potassium levels using Patiromer on gut microbiome 
dysbiosis and generation of uremic toxins. We anticipate that Patiromer will improve the 
metabolomics profile and gut permeability through binding to and removing endotoxin and 
bacteria-generated uremic toxins, and by altering the microbiome profile in ESRD patients. In 
addition, this study will unravel the effect of hyper/normo-kalemia on plasma metabolom. 
1.2 
Potential Risks and Benefits 
1.2.1 Known Potential Risks 
Patiromer is fairly safe and approved by the FDA. Most commonly observed side effects are 
hypomagnesaemia and constipation. The other study related risks is associated with the study 
procedures, which is the blood draws. 
1.2.2 Known Potential Benefits 
There are no benefits for study participants.  


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The study will add to the knowledge on the gut dysbiosis in subjects with ESRD on hemodialysis, 
the safety and efficacy of Patiromer, and changes in gut microbiome and serum metabolic 
profiles of hyperkalemic ESRD patients treated with Patiromer. 
1.3 
Study Objectives 
1.3.1 Primary Objective 
 Examine the tolerability, safety, and efficacy of Patiromer in lowering serum potassium 
levels in ESRD patients with hyperkalemia (K>5.0 mEq/L). In a non-randomized, 
crossover study, 25 ESRD patients with hyperkalemia (K>5.0 mEQ/L) will be enrolled in 
an open-label, pilot clinical trial with 3 sequential phases of (a) 2 weeks of no 
intervention, (b) 12 weeks of Patiromer treatment at 8.4-16.8 g/day, and (c) 6 weeks of 
no intervention. Blood and stool samples will be collected throughout the study period. 
1.3.2 Secondary Objectives  
 Determine the changes in gut microbiome and serum metabolome profiles of 
hyperkalemic ESRD patients treated with Patiromer. Blood and stool samples collected 
from the ESRD patients enrolled in the above study will be collected at pre-specified 
time points and analyzed by metagenomics for gut microbiome profiles, and untargeted 
and targeted metabolomics for stool and serum metabolome profiles, in order to 
determine the impact of lowering gut potassium levels using Patiromer on gut 
microbiome dysbiosis and generation of uremic toxins.  
 
 


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2 
STUDY DESIGN AND ENDPOINTS 
2.1 
Overview of Study Design 
This is an intervention study in subjects with ESRD on hemodialysis. After a screening visit, all 
eligible subjects will collect stool and provide blood samples according to Table 1.  
2.2 
Study Endpoints 
2.2.1 Primary Endpoint 
 For Specific Aim 1, the primary safety end point is adverse events during the 12 weeks of 
intervention.  
 For Specific Aim 2, the primary efficacy end points will be change in microbiome, 
metabolome and markers of inflammation.  
2.2.2 Secondary Endpoints 
 For Specific Aim 1, the Secondary efficacy end points included mean change in serum 
potassium level through 12 weeks. 
2.3 
Blinding 
This sampling study will not be blinded.  
 
 


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3 
STUDY ENROLLMENT AND WITHDRAWAL 
This is a non-randomized, crossover study. 25 ESRD patients with hyperkalemia (K>5.0 mEQ/L) 
will be enrolled in an open-label, pilot clinical trial with 3 sequential phases of (a) 2 weeks of no 
intervention, (b) 12 weeks of Patiromer treatment, and (c) 6 weeks of no intervention. 
3.1         Inclusion Criteria 
Subjects must meet all of the following criteria in order to be enrolled into the study:  
1.      Subjects on stable hemodialysis for more than 90 days   
2.      Age 18-85 years 
3.      Persistent hyperkalemia, defined as elevated serum potassium >5.0 mEq/L in more than 2 
occasions during the previous 3 months. 
4.      Ability to provide informed consent 
3.2         Exclusion Criteria 
Subjects must not meet any of the following criteria in order to be enrolled into the study: 
1. Use of pre- or probiotics during the past 2 months   
2. Use of antibiotics within the past 2 months, if the patient received a single course of 
antibiotic.  
3. Presence of chronic wound infection and osteomyelitis   
4. Inflammatory bowel disease, chronic diarrhea, current C. difficile infection   
5. Liver cirrhosis or chronic active hepatitis 
6. Treatment with immunosuppressive medications in the past 6 months or more than a week 
of treatment with prednisone >10 mg in the last 3 months 
7. Anticipated kidney transplant within 9 months  
8. Expected survival < 9 months 
9. Pregnancy, anticipated pregnancy, or breastfeeding 
10. Incarceration 
11. Participation in another intervention study 
12. Severe anemia defined as hemoglobin <8.0 g/dl any time during the last 2 months 


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3.3 
Strategies for Recruitment 
Subjects will be recruited through a search of the dialysis unit database. Potentially eligible 
subjects resulting from this database search may then be approached and offered a Screening 
Visit if interested to participate. It is anticipated that approximately 120 potential subjects will 
be screened in order to enroll 25 eligible subjects, reflecting an expected screen failure rate of 
~80%. 36 weeks is the anticipated timeframe for recruitment.  
3.4 
Subject Withdrawal or Termination 
3.4.1 Reasons for Withdrawal or Termination 
Upon enrollment, a subject may withdraw consent to participate in the study at any point 
without prejudice or consequence. Participation in this study is entirely voluntary. Likewise, a 
subject may also be withdrawn if the Investigator deems a subject unfit to continue with or 
complete the study. 
Subject withdrawal or termination may occur due to any of the following reasons: 
 Subject independently withdraws consent from the study 
 Investigator determines that the subject has developed an intercurrent illness, 
condition, becomes pregnant or experiences adverse event in which continued 
participation in the study is considered potentially harmful to the subject and 
discontinuation is in the best interest of the subject 
 Subject non-compliance (e.g. failure to comply with other protocol-specific assessments) 
 Subject is lost to follow-up  
3.4.2 Handling of Subject Withdrawals or Termination 
If a subject withdraws or is discontinued from the study before completion, every effort should 
be made to complete the assessments. The reason for subject withdrawals from the study will 
be documented in the subject’s case notes. 
Subjects will be replaced until the targeted number of subjects has been enrolled.  


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4 
STUDY PRODUCTS 
4.1 
Safe Use of Study Agent 
Patriomer is an FDA-approved orally administered drug used for the treatment of 
hyperkalemia. It is a non-absorbed polymer that binds potassium throughout the 
gastrointestinal tract and leads to lowering serum potassium levels (1). Prior Patiromer clinical 
trials have demonstrated the drug’s utility in treating hyperkalemia in patients with diabetic 
kidney disease (1; 2). Adverse events and other safety data will be obtained at each visit. The 
most commonly reported treatment related adverse events have been hypomagnesemia 
(7.2%), constipation (4.6%), and diarrhea (2.7%).  
 This study incorporates several design elements to minimize adverse events related to the 
study agent including: 
 
Eligibility criteria that exclude individuals with normal or low blood potassium levels. Only 
ESRD patients with hyperkalemia (K>5.0 mEQ/L) will be enrolled 
 
A maximum daily Patiromer dose of 16.8 g once daily 
 
Frequent monitoring of gastrointestinal symptoms  
 
Regular monitoring of concomitant medications and antibiotic use 
 
Pre-dialysis serum potassium will be monitored at regular intervals. Appropriate adjustment 
in dialysate potassium will be made to avoid hypokalemia.  
 
Follow-up of serum magnesium levels   
4.2 
Study Agent Dose Adjustments 
4.2.1 
Protocolized Dosing of Study Agent 
Participants will orally self-administer Patiromer at a dose of 8.4 gram, once daily and observed 
for a week, during which serum potassium and gastrointestinal symptoms will be evaluated. If 
tolerated and in the absence of hypokalemia (serum potassium less than 4 meq/L), the dose 
will be up-titrated to 16.8 g once daily. Participants will remain on the 16.8 g daily dosage for 
another 11 weeks, for a total of 12 weeks of treatment.  Study agent kits will contain 4 weeks’ 


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worth of doses, and will be distributed three times during the course of the study. Pharmaco-
adherence will be ensured and confirmed through frequent communications and pill count. 


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5 
ADVERSE EVENTS 
This section describes the requirements and processes for reporting adverse events and 
unanticipated problems that occur during the study to Relypsa and the IRB.  
5.1 
Definitions 
Definitions are per the January 2007 Guidance on Reviewing and Reporting Unanticipated 
Problems Involving Risks to Participants or Others and Adverse Events, Office on Human 
Research Protection (OHRP) Guidance. http://www.hhs.gov/ohrp/policy/AdvEvntGuid.htm. The 
requirements and processes for reporting adverse events are described in the corresponding 
NIH Guidelines.  
Adverse Event (AE): An AE is any untoward or unfavorable medical occurrence in a human 
study participant, including any abnormal sign (for example, abnormal physical exam or 
laboratory finding), symptom, or disease, temporally associated with the participant’s 
involvement in the research, whether or not considered related to the participant’s 
participation in the research.  
Internal adverse event:  From the perspective of one particular institution engaged in a 
multicenter clinical trial, internal adverse events are those adverse events experienced by 
participants enrolled by the investigator(s) at that institution. 
5.2 
Collecting Adverse Event Information 
The Investigator and research team is obligated to monitor participants so that their 
participation in the clinical trial is as safe as possible.  
The center staff will collect adverse event data at each study visit by checking several different 
sources of information by:  
 asking participants directly 
 evaluating medical record information 
 reviewing all laboratory values 
 examining reports generated by the data management system based on data entered into 
logs and forms   


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AE information may also be reported between scheduled study visits via regular contacts if the 
participant reports health related problems or concerns. The study period during which adverse 
events must be reported is defined as the period from initiation of the study procedures to the 
end of the treatment follow-up. In other words, AE documentation should begin when the 
patient signs the informed consent form.  
Encourage participants to contact the investigator after the conclusion of the trial if subsequent 
medical events occur which the participant, or the participant’s physician, believes may be 
related to participation in the research study.  
Other medical information 
A participant may report that he or she had a medical test or procedure. If so, inquire as to why 
this was done as it may reveal pertinent information about a medical condition or diagnosis.  In 
addition, if a participant reports starting a new medication, it may also indicate a new diagnosis 
or a change in a pre-existing medical condition that should be discussed and documented on 
the AE form.  
5.2.1.1 Serious Adverse Events 
A Serious Adverse Event (SAE) is defined as any AE that results in any of the following 
outcomes:  
 fatal 
 life-threatening 
 requires or prolongs hospital stay 
 results in persistent or significant disability or incapacity 
 results in congenital anomalies or birth defects 
 an important medical event 
Important medical events are those that may not be immediately life threatening, but are 
clearly of major clinical significance. SAE reporting requirements are based on meeting the 
outcome definition outlined above.  
 


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Note that for this trial, hospitalized is defined as staying overnight in the hospital. Time spent in 
the emergency department may or may not be reported as an SAE, depending on the reason 
for the ED visit.  
5.3 Reporting Adverse Events and Serious Adverse Events 
The Investigator must report all SAEs from the signing of the informed consent until 14 days 
after the last dose of Patiromer to Relypsa’s Drug Safety and Pharmacovigilance (DSPV) 
Department within 24 hours of becoming aware. SAE follow up information must also be 
provided as requested by Relypsa.  
All SAE reports will be sent to Relypsa’s Drug Safety by email to drugsafety@relypsa.com or via 
fax to (844) 867-7597.  The Relypsa Generic IST SAE Form will be used for reporting SAEs to 
Relypsa’s DSPV Department. All pertinent SAE information as indicated on the reporting form or 
as requested by Relypsa will be provided to facilitate safety monitoring for all patients taking 
Patiromer. These reports will be submitted by the Investigator or the research team to Relypsa 
even if it is not felt to be drug related.  Prior to the start of the study, the Investigator and 
research team will complete SAE reporting training provided by Relypsa and document 
completion of the training. 
The research team will also report any pregnancy that occurs in a female study patient or the 
male participant’s female partner or any lactation exposure occurring to an infant or child by a 
female study patient within 24 hours of become aware to Relypsa’s Drug Safety by email or fax. 
All pregnancy or lactation exposures will be reported on the Relypsa Generic IST Pregnancy or 
Lactation Report Form.  
 
 
 
 


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Figure 1. Sample collection. Stool and blood samples will be collected at weeks 1, 2, 3, 4, 6, 10, 14, 17 and 20 of the study. We will obtain 
information regarding dietary pattern and gastrointestinal health. Adverse events related to study drugs, and clinical events will also be 
collected. Patients will be requested to complete gastrointestinal (GI) health assessment survey at baseline, during treatment, and during 
post-treatment phase.  Detailed information about infection and type of antibiotic used (if any) will be collected. 
6 STUDY PROCEDURES AND SCHEDULE 
6.1 
Study Procedures/Evaluations 
6.1.1 Study Specific Assessments and Procedures 
This section describes the study specific assessments and procedures that will be conducted. Results from study specific procedures 
(e.g., laboratory evaluations or questionnaire results) will not be provided to subjects, unless the results are necessary in order to 
effectively communicate follow-up care for any adverse events that may occur as a result of participating in the study.  
 
 


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6.1.1.1 Medical History 
A detailed medical history will be obtained. Subject’s medical history will be obtained by chart 
review and interview. 
6.1.1.2 Medication History 
Subject’s medication history will be obtained during each visit, including prescription, over-the-
counter medications, and dietary supplements. 
6.1.1.3 Dietary Assessment 
Dietary assessment using the Block Food Frequency Questionnaire (https://nutritionquest.com) 
will be administered at the beginning (Week 1), during (Week 8) and end of the study (Week 
20). 
6.1.1.4 Physical Examination 
A physical examination will be conducted, which will include body measurements (including 
height, weight, and calculation of BMI) and an assessment of vital signs (blood pressure, pulse, 
body temperature).  
6.1.1.5 Biological Specimen Collection and Laboratory Evaluations 
Stool and blood specimens will be collected from all subjects. In addition, data from routine 
laboratory investigations required for standard of care will be included into the clinical 
database as deemed necessary for annotation of the stool samples to the course of clinical 
disease and treatment. 
6.1.2 Standard of Care Study Procedures 
All subjects for this study are receiving the study specific assessments solely due to study 
participation. Therefore, there are no applicable standard of care procedures associated with 
this study. 


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6.2 
Laboratory Procedures/Evaluations 
6.2.1 Clinical Laboratory Evaluations 
6.2.1.1 Serum Pregnancy Test 
A serum/urine pregnancy test will be conducted at the Screening Visit for women of 
childbearing potential.  
6.2.1.2 Hematology 
Blood samples collected at weeks 0, 2, 4, 10, 14, 17, and 20 will be tested for CBC. 
6.2.1.3 Biochemistry 
Blood samples collected at weeks 0, 2, 4, 10, 14, 17, and 20 will be tested for the 
comprehensive metabolic panel (CMP). Blood phosphorous and PTH will be tested at week 0. 
6.2.1.4 Metabolic and inflammatory biomarker studies 
Blood and stool samples will be stored for metabolomics and biomarker studies.  Both non-
biased and targeted metabolomics profiling of the stool and blood will be performed at the 
West Coast Metabolomics Center at the University of California Davis. Filtered fecal water or 
plasma samples will be used for the mass spectrometry-based metabolomics profiling. The 
process of metabolite extraction will include internal standards and follow standard protocol.  
The resulting extract will be divided into a liquid chromatography fraction and a gas 
chromatography fraction.  
6.2.1.5. Measurement of biomarkers of inflammation: Measurement of endotoxin, sCD14, hs-
CRP, IL-6 and TNF-α will be performed at weeks 1, 2, 6, 10, 14, 17 and 20 of the study. Plasma 
LPS levels will be measured using a commercially-available kinetic chromogenic limulus 
amebocyte lysate assay kit (Lonza Walkersville, Walkersville, MD). High sensitivity sandwich 
ELISAs will be used to measure plasma sCD14, hs-CRP, IL-6, and TNFα. The samples will be 
stored at -80°C and assayed at the time of initial thawing to prevent degradation. All cytokine 
assays will be performed in duplicates. If funds are available, we will also measure IL-1β, IL-2, IL-
4, IL-17, IL-10, and IL-22. 


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6.2.1.6 Measurement of specific uremic toxins and bacterial metabolites in plasma: 
Measurement of plasma p-cresol sulfate, indoxyl sulfate, TMAO and SCFA will be performed at 
2, 4, 10, 14 and 20 weeks of the study. Plasma will be separated from whole blood samples 
collected in tubes containing EDTA as anti-coagulant. Extracted plasma will be frozen 
immediately after collection and store at -80°C until further use. The chromatographic 
separation of metabolites will be performed using either reverse phase separation or normal 
phase online with QQQ mass spectrometers (Agilent Technologies). For this, we will employ a 
combination of solvents including gradients at varying concentrations of ammonium acetate, 
methanol, acentonitrile adjusted for specific metabolites. Metabolites will be separated by 
controlled flow rates on either a Luna Phenyl Hexyl column (3um, 2x150mm, Phenominex), a 
Luna Amino (NH2) column (4um, 100A 2.1x150mm, Phenominex), or an orbax Eclipse XDB-C18 
column (50 × 4.6 mm i.d.; 1.8 μm, Agilent Technologies, CA), while adjusting the temperature of 
the chamber.  All the columns used in this study will be washed and reconditioned after every 
50 injections. 
6.2.1.7 Measurement of intestinal barrier dysfunction using plasma zonulin: Commensal gut 
microbes maintain functional integrity of gut by several mechanisms, including restoration of 
tight junction protein structure.(26) Dysbiotic gut microbiome may be an important contributor 
to intestinal barrier dysfunction by altering structure and localization of TJs. Zonulin. Human 
zonulin is a <47-kDa protein that increases intestinal permeability in small intestine by 
modulating intercellular TJs.(27) Circulating zonulin in serum is considered as a useful marker of 
intestinal permeability.(27) To measure the impact of Patiromer on intestinal permeability, we 
will measure circulating zonulin levels in our study participants at 1, 2, 6, 10, 14, 17 and 20 
weeks of the study. Plasma zonulin levels will be measured using a commercially-available ELISA 
kit. 
   


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6.2.2 Other Specimen Analyses/Assays 
6.2.2.1 Gut microbiota taxonomic analysis  
The structure of the microbiota from frozen stool samples will be assessed by DNA sequencing 
and computational analysis. Stool samples will be collected for DNA extraction and shotgun 
metagenomic sequencing. DNA will be extracted using the MoBio PowerFecal DNA Isolation kit. 
Quantification and quality control of DNA samples will be run on a BioAnalyzer 2100. All 
samples will be run on an Illumina MiSeq or NextSeq, which will provide us with ~10 million 
reads per sample to allow for accurate characterization of the microbiome. Reads will be pre-
processed using PRINSEQ-lite 0.20.4 (trimming reads and bases < 25 PHRED, removing exact 
duplicates, and reads with undetermined bases). We will construct a ‘target’ genome library 
containing all bacterial, fungal, and viral sequences from the Human Microbiome Project 
Reference Database (http://www.hmpdacc.org/reference_genomes/reference_genomes.php) 
using the PathoLib module from PathoScope 2.0. We will align the reads to these libraries using 
the Bowtie2 algorithm, and then filter any reads that also aligned to the human genome (hg19) 
as implemented in PathoMap (very-sensitive-local -k 100 --score-min L,20,1.0). We will then 
apply PathoScope 2.0, specifically the PathoID module, to obtain accurate read counts for 
downstream analysis, including mapping against both a microbial database to identify 
species/strains and calculate relative abundances to determine the impact of Patriomer on the 
gut microbiome. Analyses, including testing of abundance of target species in treated patients 
and tests of correlations of changes in abundance with changes in metabolomics will be 
performed in R and Bioconductor using packages xlsx, gtools, CHNOSZ, plyr, ggplot2, reshape2, 
gplots, Phyloseq, and DESeq2.


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6.3 
Study Schedule 
6.3.1 Schedule of Events Table 
Table 1: Study procedures and time-line 
 
 
 
 
Intervention 2 to 14 weeks 
 
 
Weeks 
0 
1 
2 
3 
4 
5 
6 
7 
8 
9 
10 
11 
12 
13 
14 
17 
20 
Physical examination  
• 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Serum/Urine Pregnancy Test1 
• 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Serum K 
 
 
 
• 
 
• 
 
• 
• 
• 
 
• 
• 
• 
 
 
 
Serum Mg++ Test 
 
 
• 
 
 
 
• 
 
 
 
 
 
 
 
• 
• 
 
Comprehensive metabolic 
panel 
• 
 
• 
 
• 
 
 
 
 
 
• 
 
 
 
• 
• 
• 
CBC 
• 
 
• 
 
• 
 
 
 
 
 
• 
 
 
 
• 
• 
• 
Study medication dispensing 
 
 
• 
 
 
 
• 
 
 
 
• 
 
 
 
 
 
 
Blood sample collection 
 
• 
• 
• 
• 
 
• 
 
 
 
• 
 
 
 
• 
• 
• 
Endotoxin, sCD14, Zonulin 
and inflammatory 
biomarkers*† 
 
• 
• 
 
 
 
• 
 
 
 
• 
 
 
 
• 
• 
• 
Stool sample collection 
 
• 
• 
• 
• 
 
• 
 
 
 
• 
 
 
 
• 
• 
• 
Microbiome studies 
(Metagenomics)† 
 
• 
• 
 
• 
 
• 
 
 
 
• 
 
 
 
• 
• 
• 
Metabolomics† 
 
 
• 
 
• 
 
 
 
 
 
• 
 
 
 
• 
 
• 
Gastrointestinal health 
assessment survey 
 
• 
 
 
 
 
 
 
• 
 
 
 
 
 
• 
 
• 
Dietary assessment using 
food frequency questionnaire 
 
• 
 
 
 
 
 
 
• 
 
 
 
 
 
 
 
• 
Phosphorous and PTH‡ 
• 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
Dialysis prescription and 
medication reconciliation‡ 
• 
• 
• 
 
 
 
• 
 
 
 
• 
 
 
 
• 
• 
• 
† A purposeful approach to analyzing the stored blood and stool samples will be used.  
‡ Extracted from dialysis unit medical record  periodically when new results are available  
*hs-CRP, IL-6, and TNF-α   
1 For women of child bearing potential 


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The following will be collected monthly from the dialysis unit: 
 Routine labs from dialysis unit including comprehensive metabolic panel, Mg++, 
hematological parameters, iron profile and dialysis adequacy 
 Medication use including EPO, iron, proton pump inhibitor, phosphate binders, use of 
other potassium lowering agents, and vitamin D 
 Data about infection, antibiotic use and adverse reaction to study drug will be collected by 
the study coordinator from personal interview with the patient, dialysis unit and 
inpatient/outpatient records 
6.3.2 Screening Visit (Week 0) 
Patients who appear eligible based on pre-screening will be approached in person to determine 
interest in participation and confirm eligibility.  Study personnel will discuss the study goals and 
procedures with the potential participant in detail.  Patients should have an understanding of 
the importance of providing frequent stool samples and what the process entails.  If the patient 
agrees to participate in the study, study personnel will review and assess understanding of the 
entire informed consent form prior to obtaining written informed consent from the participant.  
The consenting process will be performed by a qualified investigator or study site designee.  
Informed consent will be obtained and documented before any study procedures are 
performed.  
The following activities may take place over one or two visits.   
 Determination of eligibility 
 Informed consent process 
 Collection of baseline data including demographics, medical history, and medication use 
including recent and current use of prescription products, over-the-counter products, 
herbal supplements, vitamins, and prebiotic and probiotic use in any form.  In addition, 
medical records from the clinic facility will be reviewed to capture any non-reported data on 
recent medication use.  


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 Blood draw (13mL): Blood samples collected at Screening will be tested for the CMP, CBC, 
phosphorous and PTH.  
 Serum pregnancy test for women of childbearing potential and tested at local lab.   
 Instruction in stool sample collection and storage 
 Instruct enrolled participants not to change their dietary patterns, if possible, during the 
study   
6.3.3 Assigning a Participant ID 
After the participant has signed the informed consent form, assign a unique 5-digit Participant 
Identification number (PID).  Each participant should be assigned the next available PID. 
6.3.4 Stool Sample Collection 
Subjects will be provided with detailed instructions on how to collect and store their stool 
samples. Subjects will be instructed to collect samples from bowel movements at weeks 1, 2, 3, 
4, 6, 10, 14, 17, and 20. 
 


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7 Evaluations and Follow Up  
Participants will have in-person study visits at Weeks 1, 2, 3, 4, 6, 10, 14, 17 and 20.  At each 
study visit, participants will be asked about emergency room visits, hospital admissions or any 
significant clinical events that occurred since the last visit.  RCs will have weekly contact with 
participants to query them on antibiotic use in the previous week and medical records will be 
reviewed for blood potassium levels and antibiotics administered.   
Dietary assessment using the Block Food Frequency Questionnaire (https://nutritionquest.com) 
will be administered at Baseline (W1), W8 and W20. 
 
7.1 
Pre-Treatment Observation Phase [Week 1 and 2] 
The following activities will be performed during in-person visits at weeks 1 and/or 2:   
 Study Visit Assessment 
 Blood Specimen Collection 
 Stool Sample Collection 
 Antibiotic use review 
 Study medication dispensing (Week 2 only) 
 Review of adverse events 
 Dietary assessment using food frequency questionnaire (Week 1 only) 
 Gastrointestinal symptom assessment questionnaire (Week 1 only) 
 Serum Mg++ (week 2 only) 
 
Treatment Phase [Weeks 3-14] 
The following activities will be completed during in-person visits at weeks 3, 4, 6, 10 and 
14: 
 
Study Visit Assessment  
 
Review of information on clinical events and current use of medications 
 Blood K+ levels (weeks 3, 5, 7, 8, 9, 11, 12, and 13) 


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 Serum Mg++ (weeks 2, 6, 14 and 17) 
 Blood Specimen Collection  
 Stool Sample Collection 
 Gastrointestinal symptom assessment questionnaire administration (Weeks 8 and 
14) 
 Review of adverse events 
 Study medication dispensing  (Weeks 2, 6 and 10 only) 
7.1.1 
Post-Treatment Observation Phase (Weeks 15 to 20) 
The following activities will be completed during Weeks 17 and 20 
 Study Visit Assessment 
 Antibiotic use review  
 Blood Specimen Collection  
 Stool Sample Collection  
 Review adverse events 
 Review of information of clinical events and current use of medications  
 Gastrointestinal symptom assessment questionnaire administration (Week 20 only) 
 Food Frequency Questionnaire (Week 20 only) 
 
 
 
 
 
 


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8 ETHICS/PROTECTION OF HUMAN SUBJECTS  
8.1 
Institutional Review Board 
The protocol, informed consent form(s), recruitment materials, and all subject materials will be 
submitted to the IRB for review and approval. Approval of both the protocol and the consent 
form must be obtained before any subject is enrolled. Any amendment to the protocol will 
require review and approval by the IRB before the changes are implemented to the study. All 
changes to the consent form will be IRB approved; a determination will be made regarding 
whether previously consented subjects need to be re-consented.  
8.2 
Informed Consent Process 
8.2.1 Consent and Other Informational Documents Provided to Subjects 
Consent forms describing in detail the study agent, study procedures, and risks are given to the 
subject and written documentation of informed consent is required prior to start of sampling of 
biological specimens. Any study related, subject facing materials will also be submitted to the 
IRB for approval. 
8.2.2 Consent Procedures and Documentation 
Informed consent is a process that is initiated prior to the individual’s agreeing to participate in 
the study and continues throughout the individual’s study participation. Extensive discussion of 
risks and possible benefits of participation will be provided to the subjects. Consent forms will 
be IRB-approved and the subject will be asked to read and review the document. The 
investigator or designee will explain the research study to the subjects and answer any 
questions that may arise. All subjects will receive a verbal explanation in terms suited to their 
comprehension of the purposes, procedures, and potential risks of the study and of their rights 
as research subjects. Subjects will have the opportunity to carefully review the written consent 
form and ask questions prior to signing. The subjects will have the opportunity to discuss the 
study with their surrogates or think about it prior to agreeing to participate. The subject will 
sign the informed consent document prior to any procedures being done specifically for the 
study. The rights and welfare of the subjects will be protected by emphasizing to them that the 


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quality of their medical care will not be adversely affected if they decline to participate in this 
study. The subjects may withdraw consent at any time throughout the course of the study.  
The original signed informed consent form will be retained in the subject’s records. A copy of 
the informed consent document will be given to the subject for their records. Documentation 
of the informed consent process will be captured in the source documents. 
8.3 
Subject and Data Confidentiality 
The investigator will ensure to comply with all applicable federal, state, and local laws and 
regulations relating to the privacy of subjects’ health information, including, but not limited to, 
the Standards for Individually Identifiable Health Information, 45 CFR Parts 160 and 164 (the 
Health Insurance Portability and Accountability Act of 1996 privacy regulation [HIPAA]). The 
investigator shall ensure that study subjects authorize the use and disclosure of protected 
health information in accordance with the privacy regulations of HIPAA and in a form 
acceptable satisfactorily to the sponsor. The study protocol, documentation, data, and all other 
information generated will be held in strict confidence. No information concerning the study or 
the data will be released to any unauthorized third party without prior written approval of the 
sponsor. 
The study monitor, other authorized representatives of the sponsor, representatives of the IRB 
may inspect all documents and records required to be maintained by the investigator, including 
but not limited to, medical records (office, clinic, or hospital) and pharmacy records for the 
subjects in this study. The clinical study site will permit access to such records.  
The study subject’s contact information will be securely stored at each clinical site for internal 
use during the study. At the end of the study, all records will continue to be kept in a secure 
location until records no longer need to be retained.  
Study subject research data, will not include the subject’s contact or identifying information. 
Subjects will be identified by their initials and an assigned unique subject identification number 
on CRFs, SAE reports, and other documents submitted to the Sponsor or Sponsor designated 
representative. 


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8.4 
Use of Stored Samples and Data Derived from Samples 
With the subject’s approval and as approved by local IRBs, de-identified biological samples will 
be stored at the GWU. These samples could be used for research into various research and 
development activities and the study of clinical indications/diseases of interest as identified by 
the PI.  
During the conduct of the study, an individual participant can choose to withdraw consent to 
have biological specimens stored for future research. However, withdrawal of consent with 
regard to biological storage will not be possible after the study is completed.  
 


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9 
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