Tralesinidase alfa (TA-ERT) is an investigational enzyme replacement therapy engineered specifically for the treatment of patients suffering from Mucopolysaccharidosis Type IIIB (MPS IIIB), also known clinically as Sanfilippo Syndrome Type B. Sanfilippo Syndrome Type B is a devastating, ultra-rare, and fatal genetic lysosomal storage disorder caused by mutations in the NAGLU gene, which leads to a severe deficiency or complete absence of the alpha-N-acetylglucosaminidase (NAGLU) enzyme. Without functional NAGLU enzyme activity, complex carbohydrates known as heparan sulfate glycosaminoglycans accumulate abnormally inside lysosomes throughout the body's tissues, particularly within the central nervous system and brain cells. This toxic accumulation causes relentless, progressive neurocognitive decline, profound developmental delays, behavioral disturbances, motor function loss, and premature mortality. Tralesinidase alfa works as an exogenous recombinant enzyme designed to replace the missing NAGLU enzyme, facilitating the breakdown and cellular clearance of accumulated heparan sulfate, with the primary clinical objective of preserving cognitive function, halting neurological degeneration, and improving overall survival outcomes for affected pediatric patients.