Status and phase
Conditions
Treatments
About
Background:
Objective:
Eligibility:
Design:
Full description
Autosomal recessive hypomorphic loss-of-function mutations in phosphoglucomutase 3 (PGM3) have been shown to result in a novel congenital disorder of glycosylation (CDG) presenting with a hyper-IgE clinical phenotype. PGM3 is required for the biosynthesis of uridine diphosphate N-acetylglucosamine (UDP-GlcNAc), a critical building block for N- and O-linked glycans, which are essential for many immune pathways in humans. PGM3 deficient patients exhibit reduced UDP-GlcNAc levels, as well as both cell specific and global defects in N- and O-linked glycosylation, respectively. Understanding how glycosylation defects result in atopic diatheses and immune dysregulation will provide novel insight into their immunopathogenesis. Developing successful therapies in these patients may further provide novel targets or approaches to the treatment of allergic diseases in the general population.
Patients with other CDGs have shown dramatic clinical improvement when given oral supplementation with mannose and fucose. Among our patients with PGM3 deficiency, in vitro supplementation with the non-diabetogenic amino-sugar N-acetylglucosamine (GlcNAc) normalized intracellular UDP-GlcNAc and surface CTLA-4 expression. We therefore propose an exploratory study to provide up to 50 patients with exogenous GlcNAc and triacetyluridine with the objectives of assessing the effects on immune function and changes in cellular glycosylation patterns. We will begin with PGM3 patients who will self-administer sequential, escalating doses of oral GlcNAc and uridine ( UMP or TAU). Given our preliminary in vitro data, we hypothesize that supplementation will provide sufficient substrate to promote increased UDP-GlcNAc, restore N- and O-linked glycans, and improve immune function in PGM3 deficient patients.
Patients will self-administer oral GlcNAc 3 times per day beginning with 12.5 mg/kg/day and increasing the dose every 2 weeks. Once a maximum tolerated dose is found (less than or equal to 100 mg/kg/day), GlcNAc supplementation will continue for 6 weeks, at which point we will add oral uridine. We will titrate uridine to find its maximum tolerated dose
(less than or equal to 200 mg/kg/day) and continue dual dosing for an additional 12 weeks. If at the end this time period there has been no change in absolute lymphocyte count, supplementation will be stopped. The dietary supplements to be used in this study have very low toxicity and have been well-tolerated in studies of patients with colitis, galactosemia, Alzheimer s, multiple sclerosis, and in treatment of 5-fluorouracil overdose.
Enrollment
Sex
Ages
Volunteers
Inclusion and exclusion criteria
Subjects must have:
EXCLUSION CRITERIA:
Primary purpose
Allocation
Interventional model
Masking
2 participants in 1 patient group
Loading...
Data sourced from clinicaltrials.gov
Clinical trials
Research sites
Resources
Legal