Abstract
Base editors can correct disease-causing genetic variants. After a neonate had received a diagnosis of severe carbamoyl-phosphate synthetase 1 deficiency, a disease with an estimated 50% mortality in early infancy, we immediately began to develop a customized lipid nanoparticle-delivered base-editing therapy. After regulatory approval had been obtained for the therapy, the patient received two infusions at approximately 7 and 8 months of age. In the 7 weeks after the initial infusion, the patient was able to receive an increased amount of dietary protein and a reduced dose of a nitrogen-scavenger medication to half the starting dose, without unacceptable adverse events and despite viral illnesses. No serious adverse events occurred. Longer follow-up is warranted to assess safety and efficacy. (Funded by the National Institutes of Health and others.).
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MeSH terms
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Ammonia / blood
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Carbamoyl-Phosphate Synthase (Ammonia) / deficiency
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Carbamoyl-Phosphate Synthase (Ammonia) / genetics
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Carbamoyl-Phosphate Synthase I Deficiency Disease* / complications
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Carbamoyl-Phosphate Synthase I Deficiency Disease* / diagnosis
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Carbamoyl-Phosphate Synthase I Deficiency Disease* / genetics
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Carbamoyl-Phosphate Synthase I Deficiency Disease* / therapy
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Gene Editing* / methods
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Genetic Therapy* / adverse effects
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Genetic Therapy* / methods
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Hepatocytes / enzymology
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Humans
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Hyperammonemia* / blood
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Hyperammonemia* / diagnosis
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Hyperammonemia* / genetics
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Hyperammonemia* / prevention & control
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Infant
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Infant, Newborn
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Liposomes / administration & dosage
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Male
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Nanoparticles / administration & dosage
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Rare Diseases* / complications
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Rare Diseases* / diagnosis
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Rare Diseases* / genetics
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Rare Diseases* / therapy
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Treatment Outcome
Substances
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Carbamoyl-Phosphate Synthase (Ammonia)
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Lipid Nanoparticles
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Liposomes
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CPS1 protein, human
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Ammonia