NCT03771105

Brief Summary

Determine the association between duration and dose of chronic conventional therapy with Pi and renal (nephrocalcinosis/nephrolithiasis), vascular (endothelial function), and cardiovascular function (echo- cardiography) in patients with hereditary hypophosphatemic rickets with hypercalciuria (HHRH) and patients with X-linked hypophosphatemia (XLH).

Trial Health

33
At Risk

Trial Health Score

Automated assessment based on enrollment pace, timeline, and geographic reach

Trial has exceeded expected completion date
Trial recruitment is currently suspended
Enrollment
30

participants targeted

Target at P50-P75 for early_phase_1

Timeline
Completed

Started Jan 2019

Longer than P75 for early_phase_1

Geographic Reach
1 country

1 active site

Status
suspended

Health score is calculated from publicly available data and should be used for screening purposes only.

Trial Relationships

Click on a node to explore related trials.

Study Timeline

Key milestones and dates

First Submitted

Initial submission to the registry

December 7, 2018

Completed
3 days until next milestone

First Posted

Study publicly available on registry

December 10, 2018

Completed
22 days until next milestone

Study Start

First participant enrolled

January 1, 2019

Completed
7.3 years until next milestone

Primary Completion

Last participant's last visit for primary outcome

April 1, 2026

Completed
Same day until next milestone

Study Completion

Last participant's last visit for all outcomes

April 1, 2026

Completed
Last Updated

May 23, 2025

Status Verified

May 1, 2025

Enrollment Period

7.3 years

First QC Date

December 7, 2018

Last Update Submit

May 22, 2025

Conditions

HypophosphatemiaRicketsHypercalciuriaXLHHHRH

Outcome Measures

Primary Outcomes (2)

  • Parathyroid Hormone (PTH) levels

    PTH levels are expected to increase over baseline after phosphate supplement (Pi).

    30 days

  • Fibroblast Growth Factor 23 (FGF23) levels

    FGF23 levels are expected to increase over baseline after phosphate supplement (Pi).

    30 days

Study Arms (4)

Patients with hereditary hypophosphatemic rickets with HHRH

EXPERIMENTAL

Hereditary hypophosphatemic rickets with hypercalciuria (HHRH)

Drug: phosphate

Patients with X-linked Hypophosphatemia

ACTIVE COMPARATOR

Patients with X-linked hypophosphatemia

Drug: phosphate

15 Patients with X-linked Hypophosphatemia

ACTIVE COMPARATOR

15 Patients with X-linked Hypophosphatemia that will receive phosphate treatment for 30 days.

Drug: phosphate

15 Patients Hereditary hypophosphatemic rickets with HHRH

ACTIVE COMPARATOR

15 patients withHereditary hypophosphatemic rickets with hypercalciuria (HHRH) that will receive phosphate treatment for 30 days.

Drug: phosphate

Interventions

phosphateDRUG

The target daily phosphate (Pi) intake is 3,500 mg/day (dietary intake plus our supplementation) for this study. Subjects will take a supplement of Pi (as KPhos Neutral 250 mg/tablet) to reach this target. Subjects will receive treatment for 30 days.

15 Patients Hereditary hypophosphatemic rickets with HHRH15 Patients with X-linked HypophosphatemiaPatients with X-linked HypophosphatemiaPatients with hereditary hypophosphatemic rickets with HHRH

Eligibility Criteria

Age13 Years+
Sexall
Healthy VolunteersNo
Age GroupsChild (0-17), Adult (18-64), Older Adult (65+)

You may qualify if:

  • Children above the age of 13 years
  • Younger and older adults with XLH and HHRH with confirmed NPT2c mutations affecting both copies of the NPT2c gene (HHRH) or one copy of the PHEX gene (XLH)
  • Be willing to provide access to prior medical records to determine eligibility including imaging, biochemical, medical, and surgical history data
  • Be willing and able to complete all aspects of the study
  • Be willing to adhere to the study visit schedule and comply with the assessments (in the opinion of the investigator).

You may not qualify if:

  • Subjects will be excluded, if they are children younger than age 13 years
  • Subjects that have other diseases likely to impact bone and mineral metabolism (e.g. renal, hepatic, gastrointestinal disorders, and malignancy),
  • Subjects that are currently pregnant,
  • Subjects that received medical therapy or developed any condition, which in the opinion of the investigator, could present a concern for either subject safety or difficulty with data interpretation.
  • Subjects will be excluded from Aim 2, if they are unable to tolerate supplemental phosphate.

Contact the study team to confirm eligibility.

Sponsors & Collaborators

Study Sites (1)

Yale University School of Medicine

New Haven, Connecticut, 06511, United States

Location

MeSH Terms

Conditions

HypophosphatemiaRicketsHypercalciuria

Interventions

Phosphates

Condition Hierarchy (Ancestors)

Phosphorus Metabolism DisordersMetabolic DiseasesNutritional and Metabolic DiseasesBone Diseases, MetabolicBone DiseasesMusculoskeletal DiseasesCalcium Metabolism DisordersVitamin D DeficiencyAvitaminosisDeficiency DiseasesMalnutritionNutrition DisordersUrological ManifestationsSigns and SymptomsPathological Conditions, Signs and Symptoms

Intervention Hierarchy (Ancestors)

Phosphoric AcidsPhosphorus AcidsAcids, NoncarboxylicAcidsInorganic ChemicalsAnionsIonsElectrolytesPhosphorus Compounds

Study Officials

  • Clemens Bergwitz, MD

    Yale University

    PRINCIPAL INVESTIGATOR

Study Design

Study Type
interventional
Phase
early phase 1
Allocation
NON RANDOMIZED
Masking
NONE
Masking Details
crossover parallel
Purpose
TREATMENT
Intervention Model
PARALLEL
Sponsor Type
OTHER
Responsible Party
SPONSOR

Study Record Dates

First Submitted

December 7, 2018

First Posted

December 10, 2018

Study Start

January 1, 2019

Primary Completion

April 1, 2026

Study Completion

April 1, 2026

Last Updated

May 23, 2025

Record last verified: 2025-05

Locations

US(1)