Chronic Kidney DiseaseNCT01475760
A Study to Evaluate Chitosan Chewing Gum in Patients With Chronic Kidney Disease
A study testing K2CG chewing gum (20mg chitosan) and K2CG chewing gum (60mg chitosan) in people with Chronic Kidney Disease, run by Denver Nephrologists, P.C. at 4 sites in United States.
Trial summary
The purpose of this study is to determine the efficacy of chitosan chewing gum (K2CG) in reducing serum phosphorus in subjects with chronic kidney disease. Read more about this study
- Who is it for?
- Ages 18 years and older
- Conditions the study is for
- Chronic Kidney Disease
- What is being tested?
- K2CG chewing gum (20mg chitosan) and K2CG chewing gum (60mg chitosan)
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 167 participants
- Where
- 4 sitesUnited States
- Study dates
- Nov 2011to Mar 2012
- Phase
- Interventional
- Are there results?
- None posted in the registry
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 18 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Who may be able to join
- Men or women > 18 years of age;
- The subject has voluntarily signed and dated the most recent informed consent form approved by an Institutional Review Board (IRB);
- The subject will, in the opinion of the investigator, be compliant with prescribed therapy and all study visits;
- Subject must be able to communicate and be able to understand and comply with the requirements of the study;
- For subjects not on dialysis estimated GFR at screening < or equal to 60 ml/min + 10 % that in the opinion of the investigator is stable and not expected to initiate dialysis within 3 months;
- Subject must have serum phosphorus at screening of greater than or equal to 3.5 mg/dL;
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- Subjects must have a screening salivary flow rate by Saxon test ≥ 1 g/2 min;
- All subjects must have NO change in prescribed dose or frequency of any of the following medications ≥ 14 days prior to Run-In Visit 2 (Day -15):
- Phosphate binding products including prescribed and over-the counter b. Oral or injectable active vitamin D c. Oral nutritional vitamin D d. Calcium supplements e. Anti-osteoporotic medication (e.g. bisphosphonates) f. Cinacalcet i. Subject must be prescribed a diet appropriate for patients with their stage of CKD, must be willing to avoid intentional changes in diet and must have stable nutritional status in the opinion of the investigator.
- Subjects on dialysis must, in the opinion of the investigator, have a stable dialysis prescription, stable dialysis access and a URR >/= 65% for at least 4 weeks prior to Day -15.
Who cannot join
- Subject is receiving or has received an investigational product (or is currently using an investigational device) within 14 days prior to Visit 2 (Day -15);
- Subject has a known sensitivity to chitin or allergy to shellfish;
- Subject has had dental work other than cleaning, cavity filling or crown placement within 48 hours prior to Visit 4 (Day 1) or at any time during the course of the trial;
- Subject has a clinically significant infection requiring treatment with antibiotics (within 7 days prior to Visit 2 (Day -15));
- Subject has had an inpatient hospitalization within 14 days prior to Visit 2 (Day -15) with the exception of hospitalizations related to vascular access procedures;
- Subject has a known history of immunodeficiency diseases, including a positive HIV (ELISA and Western blot) test result;
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- Active drug or alcohol dependence or abuse (excluding tobacco use) in the opinion of the principal investigator;
- In the opinion of the investigator, subject is unable to chew gum for 30 minutes;
- Subject has an unstable medical condition which in the opinion of the investigator would compromise successful completion of the study;
- Subject is receiving calcimimetic therapy (acceptable if subject is on dialysis);
- Subject has known salivary gland dysfunction or Sjogren's syndrome;
- Subjects is receiving niacin therapy within 7 days prior to Run- In Visit 2(Day -15) (use as part of standard multivitamin is acceptable);
- Subject has had a major cardiovascular event within 90 days of screening. The investigator should be guided by evidence of any of the following;
- Acute myocardial infarction b. Acute cerebral vascular event c. Vascular surgical intervention d. Coronary Revascularization e. Decompensated congestive heart failure
- -
Trial locations and contacts
4 sites in 1 country.
United States4 sites
Denver Nephrologists, PC
Denver, Colorado, 80230
Pacific Renal Research Institute
Meridian, Idaho, 83642
Renal Associates, PA
San Antonio, Texas, 78215
Southwest Clinical Reserach Institute, LLC
Tempe, Arizona, 85284
About this study
Official title: A Multi-Center, Open Label Study to Evaluate Chitosan Chewing Gum in Patients With Chronic Kidney Disease
The purpose of this study is to determine the efficacy of chitosan chewing gum (K2CG) in reducing serum phosphorus in subjects with chronic kidney disease.
Read the detailed description
Given the public health importance of increased P levels in the general population and specifically in patients with chronic kidney disease, it is of great importance to evaluate the ability of a medical food such as K2CG to reduce elevated serum P levels. In patients with CKD receiving dialysis it has been estimated that sustained control of serum P may result in an approximate 17% reduction in mortality.
The investigators have conducted a previous pilot double blind randomized controlled study of K2CG 20 mg and 40 mg BID for 4 weeks in 90 patients with ESRD. In this initial study the investigators did not observe a statistically significant reduction in either serum P or salivary P with active therapy as compared to placebo. However, a clear trend towards a reduction in serum P was seen in the randomized phase of the study with the active gum administered twice a day. During the open-label period where the gum was administered thrice-daily the investigators did see a statistically significant reduction in serum P of 0.3 mg/dL. Moreover, in patients with CKD not on dialysis, the investigators observed a reduction in mean serum P of approximately 0.2 mg/dL. While not statistically significant, this trial was not powered to detect this level of change in serum P and was underpowered to do so.. Differences in this range (0.2-0.4 mg/dL) have been reported in studies utilizing dietary manipulation (plant protein versus animal protein) and with the use of Niacin and are felt to be clinically meaningful reductions.
The investigators have previously also conducted a cross-sectional observational study evaluating salivary P levels across a wide spectrum of eGFR. The data indicate that mean salivary P is uniformly increased (15-25 mg/dL) relative to serum P (2.5- 4.5 mg/dL) being approximately 5-7X higher as shown below (group 1 = eGFR > 90, group 7= eGFR < 15). Importantly, salivary P was similar across the entire spectrum of eGFR.
The investigators have previously conducted a clinical trial evaluating several different formulations of K2CG with varying amounts of chitosan loading into the gum base, variable weights of gum base and 2 different formulations of gum base. In these trials the investigators further studied the effects of gum chewing in either the fasted or fed state and the effects of varying amounts of gum chewing time. Results from this study have demonstrated that the maximal amount of P loading into the K2CG is seen with the 1g chewing gum containing 20 mg chitosan and that the maximal effect is seen with 30 minutes of gum chewing.
Based on data from this study the investigators have chosen this strength/formulation for the primary efficacy endpoint assessment in the current protocol. Similar efficacy results with regard to total P loading per chewing gum were seen with the 2.0 gram, 60 mg chitosan chewing gum and there was an indication that subjects had a subjective preference for this formulation. As a result, this protocol will also assess (as a secondary efficacy endpoint) the reduction in serum P with this strength/formulation during an open label phase only in those subjects who have responded during the primary efficacy assessment phase. This will allow a comparison of efficacy between the 2 gum sizes/strengths among known 'responders' with regard to serum P reduction.
- Conditions
- Chronic Kidney Disease
- Being tested
- K2CG chewing gum (20mg chitosan), K2CG chewing gum (60mg chitosan)
- Keywords
- chronic kidney disease, serum phosphorus, salivary phosphorus, FGF23
- Medical subject headings
- Renal Insufficiency, Chronic
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
K2CG chewing gum (20mg chitosan)Other
All participating subjects will chew gum TID for 14 days beginning on Day 1 through Day 14
K2CG chewing gum (60mg chitosan)Other
Subjects will be randomized in a 1:1 fashion to either chew gum or continue with Standard of Care (no intervention)if they have a change in serum phosphorus of greater than or equal to -0.2 mg/dL from:
Baseline (defined as the mean of values from Visit 2, 3, and 4) to the end of active treatment (defined as the mean of Visit 6 and 7) AND/OR Baseline (defined as the mean of values from Visit 2, 3, and 4) and end of wash out (defined as Visit 7 (Day 22).
If randomized: Chew gum TID for 14 days beginning on Day 29 through Day 42
| Study group | Role | What they receive |
|---|---|---|
| K2CG chewing gum (20 mg chitosan) | Active comparator | Not described Receives: Other: K2CG chewing gum (20mg chitosan) |
| K2CG chewing gum (60 mg chitosan) | Active comparator | Not described Receives: Other: K2CG chewing gum (60mg chitosan) |
| Standard of Care | No intervention | Not described |
What is being measured
The primary outcome is the main question the study is designed to answer.
serum phosphorus
Change in serum phosphorus from baseline to mean of values during 2 week active chewing period in patients with CKD not on dialysis
Measured: change from baseline to mean during 2 weeks active therapy
Secondary outcomes (2)
serum phosphorus
change in serum phosphorus from baseline to mean of values during active therapy in patients with CKD on dialysis
Measured: change from baseline after 2 weeks active chewing
salivary phosphorus
change in salivary phosphorus from baseline to mean of values during 2 weeks active
Measured: change from baseline to mean during active therapy -2 weeks
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted21 Nov 2011 (estimated)
- Study startNov 2011
- Primary completionMar 2012
- Study completionMar 2012
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Chronic Kidney DiseaseStudies of the same condition, open and under way.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase N/A
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Single group
- Masking
- Single blind
- Who is masked
- Participant
- Enrolment
- 167 participants (actual)
Sponsor and investigators
- Lead sponsor
- Denver Nephrologists, P.C.
- Sponsor type
- University, hospital or other
- Collaborators
- CM&D Pharma Limited
- Responsible party
- Sponsor
- Investigators
- Geoffrey Block, MD, Principal investigator, DenverNephrologists, P.C.
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT01475760
- Sponsor's protocol ID
- CMD007
- Status last verified
- Aug 2012
- First submitted
- 17 Nov 2011
- Last updated
- 2 Aug 2012
- Results posted
- No
- Data monitoring committee
- No
Publications
Natale P, Green SC, Ruospo M, Craig JC, Vecchio M, Elder GJ, Strippoli GF. Phosphate binders for preventing and treating chronic kidney disease-mineral and bone disorder (CKD-MBD). Cochrane Database Syst Rev. 2025 Jun 27;6(6):CD006023. doi: 10.1002/14651858.CD006023.pub4.
PubMed 40576086Block GA, Persky MS, Shamblin BM, Baltazar MF, Singh B, Sharma A, Pergola P, Smits G, Comelli MC. Effect of salivary phosphate-binding chewing gum on serum phosphate in chronic kidney disease. Nephron Clin Pract. 2013;123(1-2):93-101. doi: 10.1159/000351850. Epub 2013 Jun 22.
PubMed 23797006
Study at a glance
From the registry record, last updated by the sponsor on 2 Aug 2012. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- A Multi-Center, Open Label Study to Evaluate Chitosan Chewing Gum in Patients With Chronic Kidney Disease
- ClinicalTrials.gov ID
- NCT01475760
- Acronym / sponsor ID
- CMD007
- Conditions
- Chronic Kidney Disease
- Keywords
- chronic kidney disease, serum phosphorus, salivary phosphorus, FGF23
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 167 participants (actual)
- Lead sponsor
- Denver Nephrologists, P.C.University, hospital or other
- Collaborators
- CM&D Pharma Limited
- Study start
- Nov 2011
- Primary completion
- Mar 2012 (actual)
- Study completion
- Mar 2012 (actual)
- First posted
- 21 Nov 2011 (estimated)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
The purpose of this study is to determine the efficacy of chitosan chewing gum (K2CG) in reducing serum phosphorus in subjects with chronic kidney disease.
Detailed description
Given the public health importance of increased P levels in the general population and specifically in patients with chronic kidney disease, it is of great importance to evaluate the ability of a medical food such as K2CG to reduce elevated serum P levels. In patients with CKD receiving dialysis it has been estimated that sustained control of serum P may result in an approximate 17% reduction in mortality.
The investigators have conducted a previous pilot double blind randomized controlled study of K2CG 20 mg and 40 mg BID for 4 weeks in 90 patients with ESRD. In this initial study the investigators did not observe a statistically significant reduction in either serum P or salivary P with active therapy as compared to placebo. However, a clear trend towards a reduction in serum P was seen in the randomized phase of the study with the active gum administered twice a day. During the open-label period where the gum was administered thrice-daily the investigators did see a statistically significant reduction in serum P of 0.3 mg/dL. Moreover, in patients with CKD not on dialysis, the investigators observed a reduction in mean serum P of approximately 0.2 mg/dL. While not statistically significant, this trial was not powered to detect this level of change in serum P and was underpowered to do so.. Differences in this range (0.2-0.4 mg/dL) have been reported in studies utilizing dietary manipulation (plant protein versus animal protein) and with the use of Niacin and are felt to be clinically meaningful reductions.
The investigators have previously also conducted a cross-sectional observational study evaluating salivary P levels across a wide spectrum of eGFR. The data indicate that mean salivary P is uniformly increased (15-25 mg/dL) relative to serum P (2.5- 4.5 mg/dL) being approximately 5-7X higher as shown below (group 1 = eGFR > 90, group 7= eGFR < 15). Importantly, salivary P was similar across the entire spectrum of eGFR.
The investigators have previously conducted a clinical trial evaluating several different formulations of K2CG with varying amounts of chitosan loading into the gum base, variable weights of gum base and 2 different formulations of gum base. In these trials the investigators further studied the effects of gum chewing in either the fasted or fed state and the effects of varying amounts of gum chewing time. Results from this study have demonstrated that the maximal amount of P loading into the K2CG is seen with the 1g chewing gum containing 20 mg chitosan and that the maximal effect is seen with 30 minutes of gum chewing.
Based on data from this study the investigators have chosen this strength/formulation for the primary efficacy endpoint assessment in the current protocol. Similar efficacy results with regard to total P loading per chewing gum were seen with the 2.0 gram, 60 mg chitosan chewing gum and there was an indication that subjects had a subjective preference for this formulation. As a result, this protocol will also assess (as a secondary efficacy endpoint) the reduction in serum P with this strength/formulation during an open label phase only in those subjects who have responded during the primary efficacy assessment phase. This will allow a comparison of efficacy between the 2 gum sizes/strengths among known 'responders' with regard to serum P reduction.
Study design
- Primary purpose
- Treatment
- Allocation
- Randomised
- Intervention model
- Single group
- Masking
- Single blind (participant)
- Number of arms
- 3
| Arm | Type | Receives |
|---|---|---|
| K2CG chewing gum (20 mg chitosan) | Active comparator | Other: K2CG chewing gum (20mg chitosan) |
| K2CG chewing gum (60 mg chitosan) | Active comparator | Other: K2CG chewing gum (60mg chitosan) |
| Standard of Care | No intervention | – |
Who may qualify
- Ages
- 18 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (10 listed)
- Men or women > 18 years of age;
- The subject has voluntarily signed and dated the most recent informed consent form approved by an Institutional Review Board (IRB);
- The subject will, in the opinion of the investigator, be compliant with prescribed therapy and all study visits;
- Subject must be able to communicate and be able to understand and comply with the requirements of the study;
- For subjects not on dialysis estimated GFR at screening < or equal to 60 ml/min + 10 % that in the opinion of the investigator is stable and not expected to initiate dialysis within 3 months;
Key exclusion criteria (15 listed)
- Subject is receiving or has received an investigational product (or is currently using an investigational device) within 14 days prior to Visit 2 (Day -15);
- Subject has a known sensitivity to chitin or allergy to shellfish;
- Subject has had dental work other than cleaning, cavity filling or crown placement within 48 hours prior to Visit 4 (Day 1) or at any time during the course of the trial;
- Subject has a clinically significant infection requiring treatment with antibiotics (within 7 days prior to Visit 2 (Day -15));
- Subject has had an inpatient hospitalization within 14 days prior to Visit 2 (Day -15) with the exception of hospitalizations related to vascular access procedures;
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| K2CG chewing gum (20mg chitosan)All participating subjects will chew gum TID for 14 days beginning on Day 1 through Day 14 | Other | K2CG chewing gum (20 mg chitosan) |
| K2CG chewing gum (60mg chitosan)Subjects will be randomized in a 1:1 fashion to either chew gum or continue with Standard of Care (no intervention)if they have a change in serum phosphorus of greater than or equal to -0.2 mg/dL from: Baseline (defined as the mean of values from Visit 2, 3, and 4) to the end of active treatment (defined as the mean of Visit 6 and 7) AND/OR Baseline (defined as the mean of values from Visit 2, 3, and 4) and end of wash out (defined as Visit 7 (Day 22). If randomized: Chew gum TID for 14 days beginning on Day 29 through Day 42 | Other | K2CG chewing gum (60 mg chitosan) |
Primary outcome
serum phosphorus
Time frame: change from baseline to mean during 2 weeks active therapy
Change in serum phosphorus from baseline to mean of values during 2 week active chewing period in patients with CKD not on dialysis
2 secondary outcomes
serum phosphorus
Time frame: change from baseline after 2 weeks active chewing
salivary phosphorus
Time frame: change from baseline to mean during active therapy -2 weeks
Results and safety
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 2 Aug 2012.
- Derived from this study: PubMed 40576086Natale P, Green SC, Ruospo M, Craig JC, Vecchio M, Elder GJ, Strippoli GF. Phosphate binders for preventing and treating chronic kidney disease-mineral and bone disorder (CKD-MBD). Cochrane Database Syst Rev. 2025 Jun 27;6(6):CD006023. doi: 10.1002/14651858.CD006023.pub4.
- Derived from this study: PubMed 23797006Block GA, Persky MS, Shamblin BM, Baltazar MF, Singh B, Sharma A, Pergola P, Smits G, Comelli MC. Effect of salivary phosphate-binding chewing gum on serum phosphate in chronic kidney disease. Nephron Clin Pract. 2013;123(1-2):93-101. doi: 10.1159/000351850. Epub 2013 Jun 22.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Geoffrey Block, MD principal investigator
DenverNephrologists, P.C.
4 sites in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A study testing K2CG chewing gum (20mg chitosan) and K2CG chewing gum (60mg chitosan) in people with Chronic Kidney Disease, run by Denver Nephrologists, P.C. at 4 sites in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 10 inclusion and 15 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 2 Aug 2012. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 4 sites in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
The study is completed, but results are not available in the source record. That does not mean the treatment did or did not work.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
serum phosphorus (time frame: change from baseline to mean during 2 weeks active therapy). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT01475760, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 2 Aug 2012.