GlcNAc supplementation to improve tear production in NGLY1 deficiency

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

Phase 2 Interventional Icahn School of Medicine at Mount Sinai · NCT05402345

This study is testing if a dietary supplement called GlcNAc can help people with NGLY1 deficiency produce more tears and protect their eyes.

Quick facts

PhasePhase 2
Study typeInterventional
Enrollment18 (estimated)
Ages1 Year to 60 Years
SexAll
SponsorIcahn School of Medicine at Mount Sinai Academic / other
Locations2 sites (Philadelphia, Pennsylvania and 1 other locations)
Trial IDNCT05402345 on ClinicalTrials.gov

What this trial studies

This multicenter, randomized, double-blind, placebo-controlled trial investigates the effects of GlcNAc, a dietary supplement, on tear production in patients with NGLY1-CDDG, a condition that impairs tear production and can lead to eye damage. Eligible participants, aged 1 to 60 years with a confirmed diagnosis of NGLY1-CDDG, will undergo a washout period if previously on GlcNAc before being randomized to receive either GlcNAc or a placebo for 6 weeks. Following this, all participants will receive open-label GlcNAc for an additional 6 weeks, with evaluations and lab sample collections at specified intervals.

Who should consider this trial

Good fit: Ideal candidates are individuals aged 1 to 60 years with a molecularly confirmed diagnosis of NGLY1-CDDG.

Not a fit: Patients who do not have a confirmed diagnosis of NGLY1-CDDG or are outside the age range of 1 to 60 years may not benefit from this study.

Why it matters

Potential benefit: If successful, this treatment could significantly improve tear production and eye health in patients with NGLY1 deficiency.

How similar studies have performed: While this approach is novel in the context of NGLY1 deficiency, similar studies using dietary supplements for other conditions have shown promising results.

Eligibility criteria

Show full inclusion / exclusion criteria
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

Where this trial is running

Philadelphia, Pennsylvania and 1 other locations

Study contacts

How to participate

  1. Review the eligibility criteria above with your treating physician.
  2. Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
  3. Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.
Conditions NGLY1 Deficiency
Last reviewed 2026-06-13 by the Find a Trial editorial team. Information on this page is for educational purposes and is not medical advice. Always consult qualified healthcare professionals about clinical trial participation.