An Open-label Multi-cohort Dose-escalation Study to Evaluate the Tolerance, Safety, and Pharmacokinetics of GNR-055 (GENERIUM JSC, Russia) in Healthy Volunteers With a Single Intravenous Administration

GNR-055 is intended for ERT in patient with Mucopolysaccharidosis type II (MPS II), or Hunter syndrome. MPS II is a lysosomal storage disease with an X-linked recessive inheritance type, which is characterized by a decrease in the activity of the lysosomal enzyme iduronate-2-sulfatase (I2S), caused by a mutation in the IDS gene. Enzyme deficiency leads to the accumulation of glycosaminoglycans (GAG) in lysosomes, mainly fractions of heparan and dermatan sulfates. Because of the insufficient activity of iduronate sulfatase participating in the first stage of catabolism of GAG, they accumulate in lysosomes of almost all types of cells of various tissues and organs. The disease is manifested by growth retardation, damage of many organs and systems, severe deformations of bones and joints, gross facial features, pathology of the respiratory and cardiovascular systems, damage to parenchymal organs (hepatosplenomegaly), and hearing impairment. A severe form of the disease occurs with the involvement of the nervous system in the pathological process, including mental retardation, behavior anomalies, and impaired motor function. GNR 055 is a modified enzyme iduronate-2-sulfatase capable of penetrating the blood-brain barrier and thus it is expected to prevent neurodegenerative consequences and the development of cognitive deficit in the future that will allow achieving a significant improvement in the life quality and expectancy of patients with MPS II