A Natural History Study of Aspartylglucosaminuria

Lysosomal storage disorders (LSDs) are a group of inherited metabolic diseases caused by a genetic mutation resulting in deficiency or absence of a critical enzyme, leading to the accumulation of toxic deposits in cells across multiple organ systems.

Aspartylglucosaminuria (AGU) is a rare, neurodegenerative, LSD, caused by a deficiency of the aspartylglucosaminidase (AGA) enzyme, which leads to toxic accumulation of aspartylglucosamine and subsequent cellular dysfunction. AGU has been most commonly reported in people of Finnish and Nordic descent, but is present across ethnicities and is typically misdiagnosed or undiagnosed.

Aspartylglucosaminuria (AGU) is characterized by developmental delay and intellectual disability that worsens with age. Early disease is characterized by increased frequency of bacterial ear infections, recurrent ear tube placement, intestinal dysfunction, disruptive sleep patterns, skeletal abnormalities, and gait disturbances, among others. Individuals progressively lose motor and cognitive skills, develop behavioral/emotional lability and their risk of seizures increases with age. People with AGU have a shortened life span.

No prospective natural history study for AGU has been reported. This study aims to prospectively investigate the natural history of AGU, and concurrently to identify potential outcome measures that could be used in future clinical trials. No investigational product will be provided in the study.