Ignite Creation Date:
2024-05-06 @ 11:18 AM
Last Modification Date:
2024-10-26 @ 12:43 PM
Study NCT ID:
NCT03489993
Status:
COMPLETED
Last Update Posted:
2022-08-05
First Post:
2018-03-29
Brief Title:
FGF23 and Angiotensin-1-7 in Hypophosphatemia GAP
Sponsor:
Wake Forest University Health Sciences
Organization:
Wake Forest University Health Sciences
Study Overview
Official Title:
Interplay of FGF23 and Angiotensin-1-7 in Hypophosphatemia GAP
Status:
COMPLETED
Status Verified Date:
2022-03
Last Known Status:
None
Delayed Posting:
No
If Stopped, Why?:
Not Stopped
Has Expanded Access:
False
If Expanded Access, NCT#:
N/A
Has Expanded Access, NCT# Status:
N/A
Acronym:
GAP
Brief Summary:
Hereditary hypophosphatemia encompasses rare genetic conditions characterized by renal phosphate wasting Increased circulating levels of fibroblast growth factor 23 FGF23 a key regulator of phosphorus metabolism are critical to the pathophysiology of these diseases most notably in X-linked hypophosphatemia XLH Increased FGF23 induces hypertrophy and scarring in the heart in part via stimulating the traditional renin-angiotensin system RAS pathway angiotensin-converting enzyme ACEangiotensin Ang ll particularly in patients with chronic kidney disease but the effect of FGF23 on the heart in patients with FGF23-related hypophosphatemic diseases is unknown In addition the relationship between FGF23 and the angiotensin-converting enzyme 2 ACE2angiotensin-1-7 Ang-1-7 pathway of the RAS is unknown
The objective of this study is to describe the relationship between FGF23 which causes low phosphorus levels and components of the RAS in the blood and urine to help the investigators understand why the disease occurs and how to better treat it
Subjects will be identified by querying the Electronic Medical Record according to medical diagnosis Thirty subjects 2-24 years of age will be recruited from the tertiary care Pediatric Endocrinology and Pediatric Nephrology clinics at Brenner Childrens Hospital Inclusion criteria include a confirmed diagnosis of hereditary FGF23-related hypophosphatemia Clinical data will be obtained from the Electronic Medical Record Each subject will undergo study assessments at baseline 6 months and 1 year that include blood work an echocardiogram and blood pressure measurements
The primary hypothesis is that subjects with higher Ang-1-7 levels have lower rates of cardiac hypertrophy and thus are protected against high FGF23 levels The secondary hypothesis is that subjects with higher Ang-1-7 levels have lower systolic blood pressure
The objective of this study is to describe the relationship between FGF23 which causes low phosphorus levels and components of the RAS in the blood and urine to help the investigators understand why the disease occurs and how to better treat it
Subjects will be identified by querying the Electronic Medical Record according to medical diagnosis Thirty subjects 2-24 years of age will be recruited from the tertiary care Pediatric Endocrinology and Pediatric Nephrology clinics at Brenner Childrens Hospital Inclusion criteria include a confirmed diagnosis of hereditary FGF23-related hypophosphatemia Clinical data will be obtained from the Electronic Medical Record Each subject will undergo study assessments at baseline 6 months and 1 year that include blood work an echocardiogram and blood pressure measurements
The primary hypothesis is that subjects with higher Ang-1-7 levels have lower rates of cardiac hypertrophy and thus are protected against high FGF23 levels The secondary hypothesis is that subjects with higher Ang-1-7 levels have lower systolic blood pressure
Detailed Description:
Clinical data will be collected from the Electronic Medical Record including age sex parent-reported race past medical and family histories and current medications The investigators will calculate body mass index and define overweightobesity as a body mass index 85 percentile for age and sex The investigators will calculate the estimated glomerular filtration rate to measure renal function based on serum creatinine standardized to age sex and height
Blood less than 5 mL and urine samples will be collected at each study visit at the same time as routine clinical labs Ang ll and Ang-1-7 will be measured in the plasma and urine using radioimmunoassays in a CLIA-certified laboratory within the Hypertension and Vascular Research Biomarker Analytical Core at Wake Forest School of Medicine The investigators will calculate the ratio of the two peptides and in the urine standardize their values to urine creatinine In the blood creatinine calcium phosphorus and vitamin D will be collected and in the urine albumin calcium phosphorus and creatinine will be collected all per standard of care FGF23 and klotho will be analyzed in the Core via commercially available ELISAs
All patients receive baseline and if abnormal follow-up echocardiograms to evaluate for left ventricular hypertrophy
Blood pressure will be measured at clinic visits Because age sex and height define normative pediatric values the investigators will standardize blood pressure with z scores
Blood less than 5 mL and urine samples will be collected at each study visit at the same time as routine clinical labs Ang ll and Ang-1-7 will be measured in the plasma and urine using radioimmunoassays in a CLIA-certified laboratory within the Hypertension and Vascular Research Biomarker Analytical Core at Wake Forest School of Medicine The investigators will calculate the ratio of the two peptides and in the urine standardize their values to urine creatinine In the blood creatinine calcium phosphorus and vitamin D will be collected and in the urine albumin calcium phosphorus and creatinine will be collected all per standard of care FGF23 and klotho will be analyzed in the Core via commercially available ELISAs
All patients receive baseline and if abnormal follow-up echocardiograms to evaluate for left ventricular hypertrophy
Blood pressure will be measured at clinic visits Because age sex and height define normative pediatric values the investigators will standardize blood pressure with z scores
Study Oversight
Has Oversight DMC:
None
Is a FDA Regulated Drug?:
False
Is a FDA Regulated Device?:
False
Is an Unapproved Device?:
None
Is a PPSD?:
None
Is a US Export?:
None
Is an FDA AA801 Violation?:
None