A Study of GlcNAc on Tear Production in NGLY1-CDDG

July 3, 2025 updated by: Eva Morava-Kozicz

A Phase II Randomized, Multicenter, Double-Blind, Placebo-Controlled Study Evaluating Effect Of GlcNAc On Tear Production In Individuals With NGLY1-CDDG

In patients with NGLY1-CDDG, the disorder can lead to eye damage due to not being able to produce enough tears. This study is being done to see if the dietary supplement, GlcNAc, improves tear production in patients with NGLY1-CDDG.

Study Overview

Status

Status

Indicates the current recruitment status or the expanded access status.
Active, not recruiting

Conditions

Conditions

The disease, disorder, syndrome, illness, or injury that is being studied. On ClinicalTrials.gov, conditions may also include other health-related issues, such as lifespan, quality of life, and health risks.

Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.

Detailed Description

This study is a multicenter randomized, double-blind, placebo-controlled trial of GlcNAc supplementation for improvement of tear production in NGLY1-CDDG. Clinical history and screening data will be reviewed to determine subject eligibility. If a subject is already on GlcNAc, a washout period of 1 month will be required prior to consent and randomization. Interested subjects who have a molecularly confirmed diagnosis of NGLY1-CDDG will be consented. Baseline data will be collected prior to randomization at treatment initiation. Subjects will then be randomized to placebo or GlcNAc. They will be administered weight-dependent doses of GlcNAc or an equivalent volume of placebo enterally for 6 weeks, followed by open label weight-dependent doses of GlcNAc for 6 weeks. A visit for evaluation and collection of lab samples will be conducted at 6 and 12 weeks.

Study Type

Study Type

Describes the nature of a clinical study. Study types include interventional studies (also called clinical trials), observational studies (including patient registries), and expanded access.
Interventional

Enrollment (Actual)

Enrollment

The number of participants in a clinical study. The "anticipated" enrollment is the target number of participants that the researchers need for the study.
18

Phase

Phase

The stage of a clinical trial studying a drug or biological product, based on definitions developed by the U.S. Food and Drug Administration (FDA). The phase is based on the study's objective, the number of participants, and other characteristics. There are five phases: Early Phase 1 (formerly listed as Phase 0), Phase 1, Phase 2, Phase 3, and Phase 4. Not Applicable is used to describe trials without FDA-defined phases, including trials of devices or behavioral interventions.
  • Phase 2

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Study Contact

The name and contact information for the person who can answer enrollment questions for a clinical study. Each location where the study is being conducted may also have a specific contact, who may be better able to answer those questions.

Study Locations

  • United States
    • Pennsylvania
      • Philadelphia, Pennsylvania, United States, 19104
        • Children's Hospital of Philadelphia
    • Washington
      • Seattle, Washington, United States, 98105
        • Seattle Children's Hospital

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Eligibility Criteria

The key requirements that people who want to participate in a clinical study must meet or the characteristics they must have. Eligibility criteria consist of both inclusion criteria (which are required for a person to participate in the study) and exclusion criteria (which prevent a person from participating). Types of eligibility criteria include whether a study accepts healthy volunteers, has age or age group requirements, or is limited by sex.

Ages Eligible for Study

2 years to 18 years (Child, Adult)

Accepts Healthy Volunteers

No

Description

Inclusion Criteria:

  • Previously molecularly confirmed NGLY1-CDDG
  • Between the ages of 1 year old to 60 years old
  • Parent or legal guardian available to provide consent on behalf of minor subjects or adult subjects who are unable to give informed consent due to developmental disabilities. Willingness of subject or legal guardian to provide consent.
  • Non-pregnant, non-lactating female subjects of childbearing potential who are heterosexually active must agree to use a highly effective method of contraception for the duration of the study. A highly effective method of birth control is defined as one that results in a low failure rate (i.e., <1% per year) when used consistently and correctly, such as oral/injectable/inserted/implanted/transdermal contraceptives, condom with diaphragm, condom with spermicide, diaphragm with spermicide, intrauterine hormone- releasing system, or intrauterine device (IUD), or sexual abstinence. Contraception is not required where at least 6 weeks have passed since sterilization, defined as females having undergone one of the following surgeries: hysterectomy, bilateral tubal ligation or occlusion, bilateral oophorectomy, or bilateral salpingectomy; and males who are vasectomized. Contraception is not required where females are postmenopausal (defined as 12 consecutive months of spontaneous amenorrhea and age ≥51 years)..

Exclusion Criteria

  • Hypersensitivity to any of the components of the placebo
  • History of treatment with GlcNAc within 28 days of Visit 1
  • Participation in another therapeutic trial - the subject will not be permitted to participate in any other drug trial during the blinded phase and during the 28 days prior to Visit 1
  • Shellfish allergy
  • Planned eye surgery within 3 months of enrollment
  • • Females that are pregnant, nursing or less than 6 months postpartum or attempting to conceive

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

  • Primary Purpose: Treatment
  • Allocation: Randomized
  • Interventional Model: Parallel Assignment
  • Masking: Triple

Arms and Interventions

Participant Group / Arm

Participant Group / Arm

A group or subgroup of participants in a clinical trial that receives a specific intervention/treatment, or no intervention, according to the trial's protocol.
Intervention / Treatment

Intervention / Treatment

A process or action that is the focus of a clinical study. Interventions include drugs, medical devices, procedures, vaccines, and other products that are either investigational or already available. Interventions can also include noninvasive approaches, such as education or modifying diet and exercise.
Experimental: GlcNAc
GlcNAc powder
Drug: GlcNAc-GlcN
GlcNAc powder - weight-dependent dose
Placebo Comparator: Placebo
Placebo xylose
Other: Placebo
Placebo xylose

What is the study measuring?

Primary Outcome Measures

Primary Outcome Measures

In a clinical study's protocol, the planned outcome measure that is the most important for evaluating the effect of an intervention/treatment. Most clinical studies have one primary outcome measure, but some have more than one.
Outcome Measure
Measure Description
Time Frame
Difference in tear production from baseline in placebo vs GlcNAc group
Time Frame: 6 weeks
The primary endpoint of the study is the difference in tear production from baseline in individuals with NGLY1-CDDG between the placebo and the GlcNAc group after 6 weeks of blinded therapy, as measured by Schirmer II test which is a tool that helps assess the amount of tears in the eyes.
6 weeks

Secondary Outcome Measures

Secondary Outcome Measures

In a clinical study's protocol, a planned outcome measure that is not as important as the primary outcome measure for evaluating the effect of an intervention but is still of interest. Most clinical studies have more than one secondary outcome measure.
Outcome Measure
Measure Description
Time Frame
Frequency of eye infections needing treatments
Time Frame: 6 weeks, 12 weeks
Patient/family reported number of eye infections needing treatment in last month after 6 weeks of blinded therapy and at 12 weeks after 6 weeks of open-label administration of GlcNAc.
6 weeks, 12 weeks
Frequency of eye redness needing treatments
Time Frame: 6 weeks, 12 weeks
Patient/family reported frequency of eye redness after 6 weeks of blinded therapy and at 12 weeks after 6 weeks of open-label administration of GlcNAc.
6 weeks, 12 weeks
Frequency of eye tearing/watering
Time Frame: 6 weeks, 12 weeks
Patient/family reported frequency of eye tearing/watering after 6 weeks of blinded therapy and at 12 weeks after 6 weeks of open-label administration of GlcNAc.
6 weeks, 12 weeks
Frequency of light sensitivity
Time Frame: 6 weeks, 12 weeks
Patient/family reported frequency of light sensitivity after 6 weeks of blinded therapy and at 12 weeks after 6 weeks of open-label administration of GlcNAc.
6 weeks, 12 weeks
Frequency of wind sensitivity
Time Frame: 6 weeks, 12 weeks
Patient/family reported frequency of wind sensitivity after 6 weeks of blinded therapy and at 12 weeks after 6 weeks of open-label administration of GlcNAc.
6 weeks, 12 weeks
Difference in tear production from baseline
Time Frame: 12 weeks
Difference in tear production, as measured by Schirmer II test, at 12 weeks after 6 weeks of open-label administration of GlcNAc.
12 weeks

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Sponsor

The organization or person who initiates the study and who has authority and control over the study.
Eva Morava-Kozicz

Collaborators

Collaborators

An organization other than the sponsor that provides support for a clinical study. This support may include activities related to funding, design, implementation, data analysis, or reporting.
Children's Hospital of Philadelphia
Seattle Children's Hospital

Investigators

Investigators

A researcher involved in a clinical study. Related terms include site principal investigator, site sub-investigator, study chair, study director, and study principal investigator.
  • Principal Investigator: Eva Morava-Kozicz, MD, PhD, Icahn School of Medicine at Mount Sinai

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

Helpful Links

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Actual)

Study Start

The actual date on which the first participant was enrolled in a clinical study. The "anticipated" study start date is the date that the researchers think will be the study start date.
January 24, 2025

Primary Completion (Estimated)

Primary Completion

The date on which the last participant in a clinical study was examined or received an intervention to collect final data for the primary outcome measure. Whether the clinical study ended according to the protocol or was terminated does not affect this date. For clinical studies with more than one primary outcome measure with different completion dates, this term refers to the date on which data collection is completed for all the primary outcome measures. The "anticipated" primary completion date is the date that the researchers think will be the primary completion date for the study.
December 1, 2026

Study Completion (Estimated)

Study Completion

The date on which the last participant in a clinical study was examined or received an intervention/treatment to collect final data for the primary outcome measures, secondary outcome measures, and adverse events (that is, the last participant's last visit). The "anticipated" study completion date is the date that the researchers think will be the study completion date.
December 1, 2026

Study Registration Dates

First Submitted

First Submitted

The date on which the study sponsor or investigator first submitted a study record to ClinicalTrials.gov. There is typically a delay of a few days between the first submitted date and the record's availability on ClinicalTrials.gov (the first posted date).
May 28, 2022

First Submitted That Met QC Criteria

First Submitted That Met QC Criteria

The date on which the study sponsor or investigator first submits a study record that is consistent with National Library of Medicine (NLM) quality control (QC) review criteria. The sponsor or investigator may need to revise and submit a study record one or more times before NLM's QC review criteria are met. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
May 28, 2022

First Posted (Actual)

First Posted

The date on which the study record was first available on ClinicalTrials.gov after National Library of Medicine (NLM) quality control (QC) review has concluded. There is typically a delay of a few days between the date the study sponsor or investigator submitted the study record and the first posted date.
June 2, 2022

Study Record Updates

Last Update Posted (Estimated)

Last Update Posted

The most recent date on which changes to a study record were made available on ClinicalTrials.gov. There may be a delay between when the changes were submitted to ClinicalTrials.gov by the study's sponsor or investigator (the last update submitted date) and the last update posted date.
July 8, 2025

Last Update Submitted That Met QC Criteria

Last Update Submitted That Met QC Criteria

The most recent date on which the study sponsor or investigator submitted changes to a study record that are consistent with National Library of Medicine (NLM) quality control (QC) review criteria. It is the responsibility of the sponsor or investigator to ensure that the study record is consistent with the NLM QC review criteria.
July 3, 2025

Last Verified

Last Verified

The most recent date on which the study sponsor or investigator confirmed the information about a clinical study on ClinicalTrials.gov as accurate and current. If a study with a recruitment status of recruiting; not yet recruiting; or active, not recruiting has not been confirmed within the past 2 years, the study's recruitment status is shown as unknown.
July 1, 2025

More Information

Terms related to this study

Additional Relevant MeSH Terms

Other Study ID Numbers

Other Study ID Numbers

Identifiers or ID numbers other than the NCT number that are assigned to a clinical study by the study's sponsor, funders, or others. These numbers may include unique identifiers from other trial registries and National Institutes of Health grant numbers.
  • CHOP 23-020868
  • 8404 (Other Identifier: FCDGC)

Plan for Individual participant data (IPD)

Plan to Share Individual Participant Data (IPD)?

NO

Drug and device information, study documents

Studies a U.S. FDA-regulated drug product

Yes

Studies a U.S. FDA-regulated device product

No

product manufactured in and exported from the U.S.

No

This information was retrieved directly from the website clinicaltrials.gov without any changes. If you have any requests to change, remove or update your study details, please contact register@clinicaltrials.gov. As soon as a change is implemented on clinicaltrials.gov, this will be updated automatically on our website as well.

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