A congenital disorder of glycosylation (previously called carbohydrate-deficient glycoprotein syndrome) is one of several rare inborn errors of metabolism in which glycosylation of a variety of tissue proteins and/or lipids is deficient or defective. Congenital disorders of glycosylation are sometimes known as CDG syndromes. They often cause serious, sometimes fatal, malfunction of several different organ systems (especially the nervous system, muscles, and intestines) in affected infants. The most common sub-type is PMM2-CDG (formally known as CDG-Ia) where the genetic defect leads to the loss of phosphomannomutase 2 (PMM2), the enzyme responsible for the conversion of mannose-6-phosphate into mannose-1-phosphate. Presentation
The specific problems produced differ according to the particular abnormal synthesis involved. Common manifestations include ataxia; seizures; retinopathy; liver disease; coagulopathies; failure to thrive (FTT); dysmorphic features (e.g., inverted nipples and subcutaneous fat pads), pericardial effusion, and hypotonia. If an MRI is obtained; cerebellar hypoplasia is a common finding.Ocular abnormalities of CDG-Ia include: myopia, infantile esotropia, delayed visual maturation, peripheral neuropathy (PN), strabismus, nystagmus, optic disc pallor, and reduced rod function on electroretinography.Three subtypes PMM2-CDG, PMI-CDG, ALG6-CDG can cause congenital hyperinsulinism with hyperinsulinemic hypoglycemia in infancy. N-Glycosylation and known defects
A biologically very important group of carbohydrates is the asparagine (Asn)-linked, or N-linked, oligosaccharides. Their biosynthetic pathway is very complex and involves a hundred or more glycosyltransferases, glycosidases, transporters and synthases. This plethora allows for the formation of a multitude of different final oligosaccharide structures, involved in protein folding, intracellular transport/localization, protein activity, and degradation/half-life.
The primary efficacy endpoint was the time to the onset of the first adjudicated relapse on or before study day 197 evaluated by a blinded, independent, adjudication committee, who determined whether the attack met protocol-defined criteria. The trial was conducted at 82 sites in 24 countries (including the United States) in North and South America, Europe, Africa, Asia and Australia.The U.S. Food and Drug Administration (FDA) granted the application for inebilizumab orphan drug designation and granted approval of Uplizna to Viela Bio. Society and culture
Legal status
In November 2021, the Committee for Medicinal Products for Human Use (CHMP) of the European Medicines Agency (EMA) adopted a positive opinion, recommending the granting of a marketing authorization for the medicinal product Uplizna, intended for the treatment of adults with neuromyelitis optica spectrum disorders (NMOSD) who are anti-aquaporin 4 immunoglobulin G (AQP4-IgG) seropositive. The applicant for this medicinal product is Viela Bio. Names
Inebilizumab is the international nonproprietary name (INN) and the United States Adopted Name (USAN). References
Further reading
Cree BA, Bennett JL, Kim HJ, Weinshenker BG, Pittock SJ, Wingerchuk DM,  et al. (October 2019). "Inebilizumab for the treatment of neuromyelitis optica spectrum disorder (N-MOmentum): a double-blind, randomised placebo-controlled phase 2/3 trial". Lancet. 394 (10206): 1352–1363. doi:10.1016/S0140-6736(19)31817-3. PMID 31495497. S2CID 201839513. External links
"Inebilizumab". Drug Information Portal. U.S. National Library of Medicine. Clinical trial number NCT02200770 for "A Double-masked, Placebo-controlled Study With Open Label Period to Evaluate MEDI-551 in Neuromyelitis Optica and Neuromyelitis Optica Spectrum Disorders" at ClinicalTrials.gov