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CompletedNCT01324128Updated Apr 24, 2014Results posted

A Phase 3 Study to Investigate the Safety and Efficacy of PA21, a Phosphate Binder, in Dialysis Patients

A Phase 3 interventional study of PA21 (2.5 g tablet containing 500 mg iron) and Sevelamer carbonate in Chronic Kidney Disease Requiring Chronic Dialysis, sponsored by Vifor Pharma. Completed at 15 sites in 15 countries. Open to participants aged 18 Years and older. Per ClinicalTrials.gov, last updated 2014-04-24.

Sponsored by Vifor Pharma (part of CSL Limited) · Phase 3, Interventional, and Treatment

Phase
Phase 3
Study type
Interventional
Enrollment
1,059
Allocation
Randomized
Ages
18 Years and older
Sex
All
01

Study summary

This is a Phase 3, randomised, active controlled, multicentre study to investigate the safety and efficacy of PA21, a phosphate binder, for control of hyperphosphataemia in dialysis patients. The primary objective is to establish the efficacy of PA21 for lowering phosphate levels in these patients.

02

Conditions studied

  • Chronic Kidney Disease Requiring Chronic Dialysis

Keywords

  • PA21
  • Phosphate Binder
03

In context

Lead sponsor

Vifor Pharma is the lead sponsor of 22 studies on the registry; none are open to participants now.

First submitted before Vifor Pharma became part of CSL Limited.

Browse Vifor Pharma studies →All CSL Limited studies →

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years and older
Sexes eligible
All
Accepts healthy volunteers
No

Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.

Inclusion criteria

  • Dialysis patients with hyperphosphataemia (≥ 1.94 mmol/L; ≥ 6.0 mg/dL)
  • Stable dose of phosphate binder
  • Written informed consent

Exclusion criteria

Exclusion Criteria:

  • Hyper/hypo calcemia; hyper intact parathyroid hormone (iPTH)
  • Other significant medical conditions
  • Pregnancy
05

Study design

Phase
Phase 3
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
1,059 participants (actual)

Study arms

  • Experimental
    PA21 (2.5 g tablet)

    Drug: PA21 (2.5 g tablet containing 500 mg iron)

  • Active comparator
    Sevelamer carbonate

    Drug: Sevelamer carbonate

  • Other
    PA21-1 (1.25 g tablet)

    Drug: PA21-1 (1.25 g tablet containing 250 mg iron)

Interventions

06

What researchers measure

Primary outcomes

  1. Change in Serum Phosphorus Levels From Week 24 to Week 27

    Change in serum phosphorus levels compared between PA21 Maintenance Dose (MD) and PA21-1 Low Dose (LD) in Stage 2 from Week 24 to Week 27

    Time frame: Week 24, Week 27

Secondary outcomes

  1. Change in Serum Phosphorus Levels From Baseline to Week 12

    Change in serum phosphorus levels from baseline to Week 12 in the PA21 group versus the sevelamer group.

    Time frame: Week 12 post Baseline

07

Results

Posted Apr 1, 2014

Participant flow

The first 100HD subjects that completed Stage 1 in the PA21 treatment group entered Stage 2 and were randomised to PA21 Maintenance Dose (MD) or PA21-1 Low Dose (LD). Due to a randomisation error only 99 subjects were randomised into Stage 2.

Stage 1
Participant flow — Stage 1
MilestonePA21 Stage 1Sevelamer Carbonate Stage 1PA21 (MD) Stage 2PA21-1 (LD) Stage 2
Started71034900
Completed51529300
Not completed1955600
Stage 2
Participant flow — Stage 2
MilestonePA21 Stage 1Sevelamer Carbonate Stage 1PA21 (MD) Stage 2PA21-1 (LD) Stage 2
Started005049
Completed004246
Not completed0083

Outcome measures

PrimaryChange in Serum Phosphorus Levels From Week 24 to Week 27

Change in serum phosphorus levels compared between PA21 Maintenance Dose (MD) and PA21-1 Low Dose (LD) in Stage 2 from Week 24 to Week 27

Time frame:
Week 24, Week 27
Reported as:
Least squares mean · mg/dL
Change in Serum Phosphorus Levels From Week 24 to Week 27
mg/dLPA21 (MD) Stage 2PA21-1 (LD) Stage 2
Change in Serum Phosphorus Levels From Week 24 to Week 270.25 ± 0.231.92 ± 0.23
SecondaryChange in Serum Phosphorus Levels From Baseline to Week 12

Change in serum phosphorus levels from baseline to Week 12 in the PA21 group versus the sevelamer group.

Time frame:
Week 12 post Baseline
Reported as:
Least squares mean · mg/dL
Change in Serum Phosphorus Levels From Baseline to Week 12
mg/dLPA21 (2.5 g Tablet) Stage 1Sevelamer Carbonate Stage 1
Change in Serum Phosphorus Levels From Baseline to Week 12-2.19 ± 0.09-2.45 ± 0.11

Adverse events

Non-serious events are listed at a 5% frequency threshold.

Adverse event summary by group
GroupDeathsSeriousOther
PA21 Stage 1—129/707 (18.2%)426/707 (60.3%)
Sevelamer Carbonate Stage 1—69/348 (19.8%)162/348 (46.6%)
PA21-1 (LD) Stage 2—6/49 (12.2%)10/49 (20.4%)
PA21 (MD) Stage 2—2/45 (4.4%)2/45 (4.4%)
Most frequent serious events
Showing 10 of 190
Most frequent serious events
EventPA21 Stage 1Sevelamer Carbonate Stage 1PA21-1 (LD) Stage 2PA21 (MD) Stage 2
Medical device complicationsGeneral disorders1/7070/3480/491/45
Systemic inflammatory response syndromeGeneral disorders0/7070/3480/491/45
Pain in extremityMusculoskeletal and connective tissue disorders0/7070/3480/491/45
Toxic encelphalopathyNervous system disorders0/7070/3480/491/45
Arteriovenous fistula thrombosisInjury, poisoning and procedural complications3/7072/3481/490/45
Device related infectionInfections and infestations0/7072/3481/490/45
Diabetic ulcerSkin and subcutaneous tissue disorders1/7070/3481/490/45
OsteomyelitisInfections and infestations1/7071/3481/490/45
Renal transplantSurgical and medical procedures1/7071/3481/490/45
Mental impairmentNervous system disorders0/7070/3481/490/45
Most frequent other events
Most frequent other events
EventPA21 Stage 1Sevelamer Carbonate Stage 1PA21-1 (LD) Stage 2PA21 (MD) Stage 2
DiarrhoeaGastrointestinal disorders142/70726/3481/491/45
Faeces discolouredGastrointestinal disorders109/7071/3480/490/45
HyperphosphataemiaMetabolism and nutrition disorders79/70727/3487/490/45
NauseaGastrointestinal disorders51/70739/3480/491/45
HypertensionVascular disorders45/70726/3480/490/45
ConstipationGastrointestinal disorders27/70725/3480/490/45
PruritusSkin and subcutaneous tissue disorders23/7077/3483/490/45
VomitingGastrointestinal disorders31/70719/3480/490/45

Baseline characteristics

For baseline characteristics, data from All Randomised patients was used.

Age, Categorical
Age, Categorical(Participants)PA21 Stage 1Sevelamer Carbonate Stage 1Total
<=18 years000
Between 18 and 65 years512242754
>=65 years198107305
Age, Continuous
Age, Continuous(years)PA21 Stage 1Sevelamer Carbonate Stage 1Total
Mean56.3 ± 13.3555.8 ± 14.5956.2 ± 13.77
Sex: Female, Male
Sex: Female, Male(Participants)PA21 Stage 1Sevelamer Carbonate Stage 1Total
Female314129443
Male396220616
Region of Enrollment
Region of Enrollment(participants)PA21 Stage 1Sevelamer Carbonate Stage 1Total
United States345171516
Europe15977236
Russian Federation10150151
Ukraine341751
Serbia472471
Croatia19827
South Africa527
08

Study locations

15 sites
  • San Antonio, Texas 78215, United States
  • LKH St. Polten
    Sankt Pölten, 3100, Austria
  • CHU Sart Tilman
    Liège, 4000, Belgium
  • Clinical Hospital Center Rijeka
    Rijeka, 51000, Croatia
  • Dialysis Centre Fresenius Medical Care
    Sokolov, 35601, Czechia
  • KfH Nierenzentrum Berlin-Neukoelln
    Berlin, 12045, Germany
  • Vidzemes Hospital
    Valmiera, LV-4201, Latvia
  • Vilnius University Hospital Santariskiu Clinics
    Vilnius, LT-08661, Lithuania
  • Teaching Hospital no.1 of Medical University of Lodz
    Lodz, 90-153, Poland
  • Dialmed Clinic SRL
    Sibiu, 550135, Romania
  • City Mariinsky Hospital
    Saint Petersburg, 191104, Russia
  • Zvezdara Clinical Medical Center
    Belgrade, 11000, Serbia
  • Lakeview Hospital
    Benoni, 1500, South Africa
  • Mykolayiv Regional Hospital
    Mykolayiv, 54058, Ukraine
  • Dorset County Hospital NHS Foundation Trust
    Dorset, DT1 2JY, United Kingdom
09

References and documents

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 40576086 ↗
  • Sprague SM, Ketteler M, Covic AC, Floege J, Rakov V, Walpen S, Rastogi A. Long-term efficacy and safety of sucroferric oxyhydroxide in African American dialysis patients. Hemodial Int. 2018 Oct;22(4):480-491. doi: 10.1111/hdi.12663. Epub 2018 Apr 15. PubMed 29656600 ↗
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Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Apr 24, 2014, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
11

Registry details

Key details

Study ID
NCT01324128
Lead sponsor
Vifor Pharma
Collaborators
Fresenius Medical Care North America
Responsible party
Sponsor
First posted
Mar 28, 2011
Start date
Mar 2011
Primary completion
Apr 2012
Completion
Oct 2012
Results posted
Apr 1, 2014
Last update
Apr 24, 2014

Study contacts

Juergen Floege, MD
principal investigator · Medizinische Klinik II

Oversight

Data monitoring committee
Yes
View the source record on ClinicalTrials.gov ↗

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