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Completed Phase 4 Interventional Results available

A Trial to Assess the Safety and Efficacy of KRN23 in Epidermal Nevus Syndrome (ENS)

ClinicalTrials.gov ID: NCT04320316

Public ClinicalTrials.gov record NCT04320316. Field values are reproduced from the official study page; the official ClinicalTrials.gov record remains the source of truth for eligibility, enrollment, and contact information.

ClinicalTrials.gov public records Last synced Sep 5, 2026, 10:36 PM EDT

Data is sourced from official ClinicalTrials.gov public API records. Always review the official ClinicalTrials.gov record for the latest information.

Official title

An Open Label Trial to Assess the Safety and Efficacy of KRN23, an Investigational Antibody to FGF23, in a Single Pediatric Patient With Epidermal Nevus Syndrome (ENS) and Associated Hypophosphatemic Rickets

Brief summary

Reproduced verbatim from the official ClinicalTrials.gov record. Not medical advice.

KRN23 is a fully human immunoglobulin monoclonal antibody (mAb) that binds to and inhibits the activity of fibroblast growth factor 23 (FGF23), leading to an increase in serum phosphorus levels. There are multiple disorders that result in unusually high circulating levels of FGF23, which in turn result in renal phosphate wasting and reduced levels of 1,25-dihydroxy vitamin D (1,25\[OH\]2D). Across these disorders the clinical symptoms are similar and often include osteomalacia (and, in children, rickets), muscle weakness, fatigue, bone pain, and fractures. KRN23 has been studied in one of these disorders, X-linked hypophosphatemia (XLH). In single- and repeat-dose clinical studies in subjects with XLH, subcutaneous (SC) administration of KRN23 consistently increased and sustained serum phosphorus levels and tubular reabsorption of phosphate (TRP) without a major impact on urine calcium levels or vitamin D metabolism. Positive results were also observed in a nonclinical pharmacology model of XLH. It is hypothesized that KRN23 may provide clinical benefit in this patient due to the common underlying feature in this patient and in patients with XLH - abnormally elevated FGF23 in the context of low age -adjusted serum phosphorous levels. The primary objective is to study the effect of KRN23 treatment on normalizing age-adjusted fasting serum phosphorous levels in a single pediatric patient with Epidermal Nevus Syndrome associated hypophosphatemic rickets.

Study identification

NCT ID
NCT04320316
Recruitment status
Completed
Study type
Interventional
Phase
Phase 4
Enrollment
1 participant

Conditions and interventions

Eligibility (public fields only)

Age range
6 Months and older
Sex
Male
Healthy volunteers
Healthy volunteers not accepted

This page does not interpret eligibility. Detailed inclusion and exclusion criteria are on the official ClinicalTrials.gov record.

Study timeline

Start date
Jul 30, 2020
Primary completion
Jul 30, 2021
Completion
Aug 30, 2021
Last update posted
Oct 6, 2022

2020 – 2021

United States locations

U.S. sites
1
U.S. states
1
U.S. cities
1
Facility City State ZIP Site status
University of Alabama at Birmingham Birmingham Alabama 35233

Site contact phone numbers, emails, and investigator names are intentionally not displayed here. Open the official ClinicalTrials.gov record for site contact information.

About this trial record page

What this page shows
Public field values for ClinicalTrials.gov record NCT04320316, including study identification, conditions, interventions, eligibility (age, sex, healthy volunteer), timeline, and U.S. site list.
What this page does not do
No medical advice, eligibility judgments, treatment recommendations, study quality scoring, or AI-generated medical summaries. No site contact phone numbers, emails, or investigator names.
Where the data comes from
Sourced from the official ClinicalTrials.gov public API. The official record is the source of truth.
Last refresh
Last update posted Oct 6, 2022 · Synced Sep 5, 2026

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Open the official record

The complete protocol, eligibility criteria, and contact information for NCT04320316 live on ClinicalTrials.gov.

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