JR-446

JR-446 is a proprietary, blood-brain barrier (BBB)-penetrating α-N-acetylglucosaminidase enzyme replacement therapy in development for the treatment of mucopolysaccharidosis type IIIB (MPS IIIB, also known as Sanfilippo syndrome type B). Developed using JCR Pharmaceuticals' J-Brain Cargo technology, JR-446 is designed to deliver the deficient enzyme directly into the central nervous system by fusing it with an antibody targeting transferrin receptors on brain endothelial cells. This approach enables effective transport across the BBB and aims to address both neurological and somatic symptoms of MPS IIIB. There are currently no approved therapies for MPS IIIB. The drug is being evaluated in Phase I/II clinical trials in Japan, primarily involving pediatric patients[1][2][3][6][7].