A Study of GlcNAc on Tear Production in NGLY1-CDDG

Study Overview
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Brief Summary
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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.

Detailed Description
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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 4-86 weeks . A final visit for evaluation and collection of lab samples will be conducted at the end of the study.

Official Title
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Evaluation of the Safety and Effects of Oral Dietary GlcNAc Supplementation in Patients With NGLY1 Deficiency

Conditions
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NGLY1 Deficiency

Intervention / Treatment
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* Drug: GlcNAc-GlcN
* Other: Placebo


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Previously molecularly confirmed NGLY1-CDDG 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. 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
Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Masking: Triple


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: GlcNAc<br>GlcNAc eye drops | Drug: GlcNAc-GlcN<br>* GlcNAc eye drops<br>|
| Placebo Comparator: Placebo<br>Placebo eye drops | Other: Placebo<br>* Placebo eye drops<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Difference in mL in tear production in placebo vs GlcNAc group | The primary endpoint of the study is the difference in tear production in individuals with NGLY1-CDDG between the placebo and the GlcNAc group after 4-8 weeks of blinded therapy, as measured by Schirmer test. | 8 weeks |