Condition category
Urological and Genital Diseases
Date applied
06/05/2010
Date assigned
27/05/2010
Last edited
30/08/2011
Prospective/Retrospective
Retrospectively registered
Overall trial status
Completed
Recruitment status
No longer recruiting

Plain English Summary

Not provided at time of registration

Trial website

Contact information

Type

Scientific

Primary contact

Dr Marc Vervloet

ORCID ID

Contact details

De Boelelaan 1117
Amsterdam
1081 HV
Netherlands
31-20-4442673
m.vervloet@vumc.nl

Additional identifiers

EudraCT number

ClinicalTrials.gov number

Protocol/serial number

2008/155

Study information

Scientific title

Effects of changes in dietary phosphorus intake on fibroblast growth factor 23 (FGF23) levels in healthy volunteers: a controlled crossover trial

Acronym

Study hypothesis

Background:
This study is related to patients with kidney disease. Kidney disease, as defined by a decline in estimated Glomerular Filtration Rate (GFR), as even in early stages related to disturbances in the metabolism of minerals, especially calcium and phosphorus, and Fibroblast growth factor 23 (FGF23). The latter is related to clinical endpoints and mortality.

Hypothesis
Changes in phosphate intake lead to parallel changes in levels of FGF23, even in healthy volunteers. These changes in FGF23 in turn lead to increases in phosphaturia and changes in levels of 1,25 dihydroxyvitamin D, both independent from possible changes in PTH or serum phosphate levels.

Ethics approval

The local medical ethics committe (Medisch Ethische Toetsingscommissie) of Vrije University Medical Centre (VUMC) approved on the 11th of August 2008 (ref: 2008/155)

Study design

Non-randomised controlled crossover group trial

Primary study design

Interventional

Secondary study design

Non randomised controlled trial

Trial setting

Hospitals

Trial type

Other

Patient information sheet

Not available in web format, please use contact details below to request a patient information sheet

Condition

Kidney disease

Intervention

Subjects are switched from regular diet to phosphate-restricted diet for two days, and the back to regular diet for ten days. After that they are switched from regular diet to phopsphate-enriched diet and the back again. No other interventions are made.

Both the primary and secondary endpoint were determined during the interventional periods, because changes induced by the intervention are almost immediate.

Intervention type

Other

Phase

Not Applicable

Drug names

Primary outcome measures

Changes in FGF23 levels, determined using sandwich ELISA for both C-terminal FGF23 (provided by Immutopics, San Clemente, USA) and Intact FGF23 (provided by Kainos, Japan).

Secondary outcome measures

1. Changes in phosphaturia
2. Changes in levels of metaboliotes of vitamin D (1,25 dihydroxyvitamin D)
Outcomes analysed by standard laboratory techniques and radio-immuno assay (IDS, Tyne and Wear, UK) respectively

Overall trial start date

01/08/2008

Overall trial end date

31/12/2008

Reason abandoned

Eligibility

Participant inclusion criteria

1. Male or female
2. Non-smoking subjects
3. Normal renal function, as defined by estimated Glomerular Filtration Rate (GFR) above 80 ml/min.
4. Females should have a negative test for pregnancy at baseline

Participant type

Patient

Age group

Adult

Gender

Both

Target number of participants

10

Participant exclusion criteria

1. Abnormal kidney function
2. Substantial comorbidity

Recruitment start date

01/08/2008

Recruitment end date

31/12/2008

Locations

Countries of recruitment

Netherlands

Trial participating centre

De Boelelaan 1117
Amsterdam
1081 HV
Netherlands

Sponsor information

Organisation

Vrije University Medical Centre (VUMC) (Netherlands)

Sponsor details

Department of Nephrology
De Boelelaan 1117
Amsterdam
1081 HV
Netherlands
m.vervloet@vumc.nl

Sponsor type

Hospital/treatment centre

Website

Funders

Funder type

Hospital/treatment centre

Funder name

Vrije University Medical Centre (VUMC) (Netherlands) - Departments of nephrology and biochemistry

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Results and Publications

Publication and dissemination plan

Not provided at time of registration

Intention to publish date

Participant level data

Not provided at time of registration

Results - basic reporting

Publication summary

Publication citations

Additional files

Editorial Notes