-JCR Pharmaceuticals Co., Ltd. (TSE 4552; JCR) announced that it achieved the enrollment of the target number of participants in the global Phase III clinical trial of JR-141 (INN: pabinafusp alfa), which is in development for the treatment of mucopolysaccharidosis type II (MPS II, also known as Hunter syndrome). The Phase III clinical trial is ongoing in the United States, Latin America, and Europe. (JR-141-GS31)

JR-141 is a recombinant fusion protein of an antibody against the human transferrin receptor and iduronate-2-sulfatase, the enzyme that is missing or malfunctioning in people with Hunter syndrome. JR-141 was developed using J-Brain Cargo^®, JCR’s proprietary blood-brain barrier (BBB)-penetrating technology, which is designed to deliver biotherapeutics across the BBB into the central nervous system (CNS) to address the neurological symptoms of Hunter syndrome.

“This achievement is a milestone in the JR-141 clinical development program, as the Hunter syndrome community needs a therapy that treats the cognitive symptoms of this devastating and life-threatening disease for which there are inadequate treatment options available,” said Shin Ashida, Chairman, President and CEO of JCR Pharmaceuticals. “We are making good progress in this global Phase III clinical trial, and we look forward to sharing the clinical data as they are available. Thank you to all the participants who are part of this clinical trial.”

In March 2021, the Ministry of Health, Labour and Welfare (MHLW) in Japan approved JR-141 (also known by the brand name IZCARGO^®) for a lysosomal storage disorder. JR-141 is the first-ever approved ERT in the world that penetrates the BBB.