Study to Evaluate the Efficacy and Safety of PT20 in Subjects With Hyperphosphataemia and Dialysis Dependent Chronic Kidney Disease
![]() |
The safety and scientific validity of this study is the responsibility of the study sponsor and investigators. Listing a study does not mean it has been evaluated by the U.S. Federal Government. Read our disclaimer for details. |
ClinicalTrials.gov Identifier: NCT02151643 |
Recruitment Status :
Completed
First Posted : May 30, 2014
Results First Posted : January 16, 2018
Last Update Posted : January 16, 2018
|
- Study Details
- Tabular View
- Study Results
- Disclaimer
- How to Read a Study Record
Condition or disease | Intervention/treatment | Phase |
---|---|---|
Hyperphosphataemia | Drug: PT20 Drug: Placebo | Phase 2 |
PT20 represents a mechanism to address many of the limitations associated with current phosphate binding agents. The available clinical and non clinical evidence suggests that PT20 binds phosphate and prevents its uptake more efficiently than other phosphate binding drugs and may therefore either reduce the pill burden associated with controlling phosphate levels, or result in lower phosphate levels with the same pill burden.
The this study is the first to investigate the efficacy and safety of PT20 in subjects with dialysis-dependent chronic kidney disease (CKD).
Study Type : | Interventional (Clinical Trial) |
Actual Enrollment : | 153 participants |
Allocation: | Randomized |
Intervention Model: | Parallel Assignment |
Masking: | Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor) |
Primary Purpose: | Treatment |
Official Title: | Study to Evaluate the Efficacy and Safety of PT20 in Subjects With Hyperphosphataemia and Dialysis Dependent Chronic Kidney Disease |
Actual Study Start Date : | May 7, 2014 |
Actual Primary Completion Date : | March 18, 2015 |
Actual Study Completion Date : | March 18, 2015 |

Arm | Intervention/treatment |
---|---|
Experimental: Group 1 - PT20 400 mg tid
PT20 400 mg tid (1.2 g/day) administered orally. Dosing was initiated with the subject's first meal/snack following receipt of study medication at Visit 7 (Day 1). There was to be no change in dose administration level with respect to each cohort in this study |
Drug: PT20
Modified ferric oxide adipate tablets
Other Names:
|
Experimental: Group 2 - PT20 800 mg tid
PT20 800 mg tid (2.4 g/day) administered orally. Dosing was initiated with the subject's first meal/snack following receipt of study medication at Visit 7 (Day 1). There was to be no change in dose administration level with respect to each cohort in this study |
Drug: PT20
Modified ferric oxide adipate tablets
Other Names:
|
Experimental: Group 3 - PT20 1600 mg tid
PT20 1600 mg tid (4.8 g/day) administered orally. Dosing was initiated with the subject's first meal/snack following receipt of study medication at Visit 7 (Day 1). There was to be no change in dose administration level with respect to each cohort in this study |
Drug: PT20
Modified ferric oxide adipate tablets
Other Names:
|
Experimental: Group 4 - PT20 3200 mg tid
PT20 3200 mg tid (9.6 g/day) administered orally. Dosing was initiated with the subject's first meal/snack following receipt of study medication at Visit 7 (Day 1). There was to be no change in dose administration level with respect to each cohort in this study |
Drug: PT20
Modified ferric oxide adipate tablets
Other Names:
|
Placebo Comparator: Group 5 - Placebo tid
Matched Placebo (for PT20) tid administered orally. Dosing was initiated with the subject's first meal/snack following receipt of study medication at Visit 7 (Day 1). There was to be no change in dose administration level with respect to each cohort in this study |
Drug: Placebo
Placebo tablets matched to each PT20 dose arm
Other Name: Matched Placebo for PT20 |
- Change in Serum Phosphate Concentration From Baseline (Visit 7, Day 1) to Visit 11 (Day 29) [ Time Frame: Day 1 to Day 29 ]The primary efficacy endpoint was the change in serum phosphate concentration from Baseline (Visit 7, Day 1) to Visit 11 (Day 29). All study specific blood samples were collected, processed and analysed using a central laboratory.
- Change in Haemoglobin Concentration From Baseline (Visit 7, Day 1) to Visit 11 (Day 29) [ Time Frame: Day 1 to Day 29 ]Descriptive statistics were to be used to summarise values and change from Baseline (Visit 7, Day 1) to Day 29 (Visit 11) in haemoglobin concentration. An analysis of covariance (ANCOVA) was to be used to analyse the changes from Baseline (Visit 7, Day 1) to Visit 11 (Day 29), which were to include the fixed, categorical effects of treatment as well as the continuous, fixed covariates of Baseline concentrations for haemoglobin. Only those subjects with available concentrations for both Baseline (Visit 7, Day 1) and Visit 11 (Day 29) were to be included in this analysis.
- Change in Serum Ferritin Concentration From Baseline (Visit 7, Day 1) to Visit 11 (Day 29) [ Time Frame: Day 1 to Day 29 ]Descriptive statistics were to be used to summarise values and change from Baseline (Visit 7, Day 1) to Day 29 (Visit 11) in serum ferritin concentration. An analysis of covariance (ANCOVA) was to be used to analyse the changes from Baseline (Visit 7, Day 1) to Visit 11 (Day 29), which were to include the fixed, categorical effects of treatment and week (Visit), as well as the continuous, fixed covariates of Baseline concentrations for serum ferritin. Only those subjects with available concentrations for both Baseline (Visit 7, Day 1) and Visit 11 (Day 29) were to be included in this analysis.
- Change in Transferrin Saturation From Baseline (Visit 7, Day 1) to Visit 11 (Day 29) [ Time Frame: Day 1 to Day 29 ]Descriptive statistics were to be used to summarise values and change from Baseline (Visit 7, Day 1) to Day 29 (Visit 11) in transferrin saturation. An analysis of covariance (ANCOVA) was to be used to analyse the changes from Baseline (Visit 7, Day 1) to Day 29 (Visit 11), which were to include the fixed, categorical effects of treatment and week, as well as the continuous, fixed covariates of Baseline concentrations for transferrin saturation. Only those subjects with available concentrations for both Baseline (Visit 7, Day 1) and Visit 11 (Day 29) were to be included in this analysis.
- Change in Calcium x Phosphate Product From Baseline (Visit 7, Day 1) to Visit 11 (Day 29) [ Time Frame: Day 1 to Day 29 ]Descriptive statistics were to be used to summarise values and change from Baseline (Visit 7, Day 1) to Day 29 (Visit 11) in Calcium x Phosphate Product . An analysis of covariance (ANCOVA) was to be used to analyse the changes from Baseline (Visit 7, Day 1) to Day 29 (Visit 11), which were to include the fixed, categorical effects of treatment, as well as the continuous, fixed covariates of Baseline concentrations for Calcium x Phosphate Product. Only those subjects with available concentrations for both Baseline (Visit 7, Day 1) and Visit 11 (Day 29) were to be included in this analysis. In CKD subjects (Stages 3-5), the clinical recommendation (KDOQI) is that serum calcium x phosphate product should be maintained at < 55 mg^2/dL^2 (4.4 mmol^2 /L^2).
- Change in Gastrointestinal Symptom Rating System (GSRS) Overall Score From Baseline (Visit 7, Day 1) to Visit 11 (Day 29) [ Time Frame: Day 1 to Day 29 ]The GSRS assesses the impact of treatment-related GI complications. It includes 15 items divided into 5 subscales (diarrhoea, indigestion, abdominal pain, constipation, and reflux), and uses a seven-grade Likert scale to assess symptoms (1 = no discomfort at all, 7 = very severe discomfort). The total score was calculated as the average score of all 15 items. If data were missing from one or more subscales, the mean of the completed items within the subscale was to be used for the subscale score, provided that more than half of the subscale items were complete. If more than half of the items within a subscale were missing, the subscale score and overall score were also to be defined as missing. The change in overall GSRS score from Baseline (Visit 7, Day 1) to Visit 11 (Day 29) was summarised by treatment and a two-sample t-test was to be used to identify differences between the placebo and PT20 dose groups. The higher the score, the more severe the gastrointestinal symptoms.

Choosing to participate in a study is an important personal decision. Talk with your doctor and family members or friends about deciding to join a study. To learn more about this study, you or your doctor may contact the study research staff using the contacts provided below. For general information, Learn About Clinical Studies.
Ages Eligible for Study: | 18 Years to 90 Years (Adult, Older Adult) |
Sexes Eligible for Study: | All |
Accepts Healthy Volunteers: | No |
Inclusion Criteria:
- Men or women aged 18 90 years
- Subject must have a stable dialysis prescription for at least 28 days prior to start of Screening.
- Subject must have the most recent serum phosphate measurement, taken during the 28 days prior to the start of Screening, of ≥ 4.0 mg/dL and ≤ 8 mg/dL.
Exclusion Criteria:
- Subject's most recent historical pre-dialysis serum bicarbonate value within 14 days prior to the start of Screening (Visit 1) is < 18 mg/dL.
- Subject has, in the opinion of the investigator, severe chronic lung disease and/or carbon dioxide retention.

To learn more about this study, you or your doctor may contact the study research staff using the contact information provided by the sponsor.
Please refer to this study by its ClinicalTrials.gov identifier (NCT number): NCT02151643
Principal Investigator: | Geoff Block, MD | Denver Nephrologist |
Responsible Party: | Phosphate Therapeutics |
ClinicalTrials.gov Identifier: | NCT02151643 |
Other Study ID Numbers: |
PT20-201 |
First Posted: | May 30, 2014 Key Record Dates |
Results First Posted: | January 16, 2018 |
Last Update Posted: | January 16, 2018 |
Last Verified: | December 2017 |
Individual Participant Data (IPD) Sharing Statement: | |
Plan to Share IPD: | No |
Studies a U.S. FDA-regulated Drug Product: | Yes |
Studies a U.S. FDA-regulated Device Product: | No |
Dialysis Dependent Chronic Kidney Disease |
Kidney Diseases Renal Insufficiency, Chronic Hyperphosphatemia Urologic Diseases Renal Insufficiency Phosphorus Metabolism Disorders |
Metabolic Diseases Iron Trace Elements Micronutrients Physiological Effects of Drugs |