Low Phosphate Diets in Patients With Early Stages of Chronic Kidney Disease - Full Text View

Purpose

The purpose of this study is to learn more about how the kidneys control the blood levels of phosphorus in patients with early chronic kidney disease. The ultimate goal is to use this information to design improved treatment strategies for phosphorus-related problems for the millions of patients with chronic kidney disease.

Condition	Intervention
Chronic Kidney Disease	Drug: Lanthanum Carbonate Dietary Supplement: Low Phosphorus Diet Dietary Supplement: Unrestricted Phosphorus Diet Drug: Placebo

Study Type:	Interventional
Study Design:	Allocation: Randomized Endpoint Classification: Efficacy Study Intervention Model: Factorial Assignment Masking: Single Blind (Subject) Primary Purpose: Prevention
Official Title:	Reduced Phosphate Intake in "Normo-Phosphatemic" Chronic Kidney Disease Patients

Resource links provided by NLM:

MedlinePlus related topics: Chronic Kidney Disease

Drug Information available for: Lanthanum Carbonate Lanthanum Phosphorus

U.S. FDA Resources

Further study details as provided by Massachusetts General Hospital:

Primary Outcome Measures:

Fibroblast Growth Factor 23 (FGF-23) [ Time Frame: 2 weeks ] [ Designated as safety issue: No ]
Plasma FGF-23 was measured using c-terminal FGF23 assay.

Secondary Outcome Measures:

24-hour Urinary Phosphate [ Time Frame: 2 weeks ] [ Designated as safety issue: No ]
from 24-hr urine collections

Enrollment:	16
Study Start Date:	January 2007
Study Completion Date:	January 2010
Primary Completion Date:	January 2010 (Final data collection date for primary outcome measure)

Arms	Assigned Interventions
Active Comparator: Lanthanum Carbonate and Low Phosphorus Diet 25% of subjects will receive binders plus a phosphate restricted diet.	Drug: Lanthanum Carbonate Lanthanum carbonate 1000mg 3x/day Dietary Supplement: Low Phosphorus Diet Low phosphorus diet will consist of 800 mg of phosphorus per day.
Active Comparator: Lanthanum Carbonate and Unrestricted Phosphorus Diet 25% binders + unrestricted phosphate diet.	Drug: Lanthanum Carbonate Lanthanum carbonate 1000mg 3x/day Dietary Supplement: Unrestricted Phosphorus Diet Unrestricted diet will contain 1550 mg of phosphorus per day - 800 mg of which is dietary and 750mg of Neutraphos (3 packets/day); each packet is 250mg. Other Name: Neutraphos
Active Comparator: Placebo and Low Phosphorus Diet 25% placebo + phosphate restricted diet.	Dietary Supplement: Low Phosphorus Diet Low phosphorus diet will consist of 800 mg of phosphorus per day. Drug: Placebo Lanthanum Carbonate placebo given three times a day with meals.
Active Comparator: Placebo and Unrestricted Phosphorus Diet 25% placebo + unrestricted phosphate diet.	Dietary Supplement: Unrestricted Phosphorus Diet Unrestricted diet will contain 1550 mg of phosphorus per day - 800 mg of which is dietary and 750mg of Neutraphos (3 packets/day); each packet is 250mg. Other Name: Neutraphos Drug: Placebo Lanthanum Carbonate placebo given three times a day with meals.

Detailed Description:

Phosphorus is a mineral found in dairy products, nuts, and meat that is essential for bone health and many other important functions inside the body's cells. The kidneys are responsible for keeping the blood levels of phosphorus normal. Healthy kidneys do this by spilling excess phosphorus into the urine. In patients with chronic kidney disease, the kidneys are unable to spill an adequate amount of phosphorus so that excess phosphorus can accumulate in the walls of blood vessels leading to heart disease, their leading cause of death. A recently discovered hormone called FGF-23 helps control the blood levels of phosphorus by "telling" the kidney how much phosphorus to spill in the urine. The purpose of this study is to learn more about how FGF-23 helps the kidneys control the blood levels of phosphorus. The ultimate goal is to use this information to design improved treatment strategies for phosphorus-related problems for the millions of patients with chronic kidney disease.

Eligibility

Ages Eligible for Study:	18 Years to 80 Years
Genders Eligible for Study:	Both
Accepts Healthy Volunteers:	No

Criteria

Inclusion Criteria:

subjects with stage 3a, 3b and 4 CKD
subjects have to be aged 18 years or older
subjects have to have normal serum phosphate levels (< 4.6 mg/dl)
subjects have to have sufficient 25-OH Vit0amin D levels (≥ 20 ng/ml)

Exclusion Criteria:

subjects with rapidly advancing renal failure who thus might develop hyperphosphatemia or end stage renal disease requiring initiation of dialysis during the study period
subjects expected to require dialysis initiation within the follow up period
subjects with hyperphosphatemia > 4.6 mg/dL
subjects with any previous or current treatment with phosphate binders or active vitamin D (doxercalciferol or calcitriol)
subjects with malnutrition, defined as a serum albumin < 3.0 mg/dl, in order to avoid worsening protein-malnutrition status during the restricted study period since phosphate restricted diets are also low in protein
subjects with chronic gastrointestinal diseases that could impede their absorptive ability such as Crohn's disease, ulcerative colitis and sprue
subjects with liver disease (ALT or AST > 100 U/L) or cholestasis (direct bilirubin > 1.0 mg/dl) because this can limit their ability to absorb fat soluble vitamins such as vitamin D
subjects with anemia, defined as a hematocrit <27% at the screening visit
subjects wht have been hospitalization within the previous 4 weeks
subjects who are pregnant
subjects who are breastfeeding mothers
subjects with primary hypoparathyroidism
subjects with primary hyperparathyroidism
subjects with previous subtotal parathyroidectomy
subjects with previous outpatient counseling by a renal nutritionist
subjects who are unable to independently provide written informed consent - prisoners, mentally incompetent, minors

Contacts and Locations

Please refer to this study by its ClinicalTrials.gov identifier: NCT00438932

Locations

United States, Massachusetts
Massachusetts General Hospital
Boston, Massachusetts, United States, 02114

Sponsors and Collaborators

Massachusetts General Hospital

Shire Development LLC

Investigators

Principal Investigator:	Myles Wolf, MD, MMSc	Univesity of Miami Miller School of Medicine
Principal Investigator:	Harald Jueppner, MD	Massachusetts General Hospital

More Information

Publications:

Isakova T, Gutiérrez OM, Smith K, Epstein M, Keating LK, Jüppner H, Wolf M. Pilot study of dietary phosphorus restriction and phosphorus binders to target fibroblast growth factor 23 in patients with chronic kidney disease. Nephrol Dial Transplant. 2011 Feb;26(2):584-91. Epub 2010 Jul 14.

Responsible Party:	Myles S. Wolf, Associate Professor, Massachusetts General Hospital
ClinicalTrials.gov Identifier:	NCT00438932 History of Changes
Other Study ID Numbers:	2005P000486
Study First Received:	February 20, 2007
Results First Received:	July 25, 2011
Last Updated:	September 23, 2011
Health Authority:	United States: Food and Drug Administration

Keywords provided by Massachusetts General Hospital:

phosphate, phosphorus, FGF-23, PTH, 1,25D

Additional relevant MeSH terms:

Kidney Diseases
Renal Insufficiency, Chronic
Kidney Failure, Chronic
Urologic Diseases
Renal Insufficiency

ClinicalTrials.gov processed this record on May 21, 2013