October 27 , 2023 JCR Pharmaceuticals Co., Ltd. (TSE 4552; Chairman and President: Shin Ashida; “JCR”) announced today that the first patient in the Phase I/II clinical trial with Mucopolysaccharidosis Type IIIA (MPS IIIA; Sanfilippo Syndrome Type A) has been dosed with JR 441, a blood brain barrier (BBB) penetrating form of heparan N sulfatase that was developed using JCR’s proprietary J Brain Cargo ® BBB penetrating technology. JR 441 is a recombinant fusion protein of antibody fragment against the human transferrin receptor and heparan N sulfatase, the enzyme missing or malfunctioning in subjects with MPS IIIA .