JCR Pharma Begins Phase I Trial Dosing of JR-441 for MPS IIIA

HYOGO, Japan I October 31, 2024 I JCR Pharmaceuticals Co., Ltd. (TSE 4552; “JCR”) has commenced the first patient dosing in Japan for the Phase I clinical trial of JR-441. This investigational enzyme replacement therapy aims to treat mucopolysaccharidosis type IIIA (MPS IIIA), also known as Sanfilippo syndrome type A. JR-441 is a unique recombinant heparan N-sulfatase capable of crossing the blood-brain barrier (BBB).

MPS IIIA is a rare inherited disorder marked by severe central nervous system (CNS) symptoms, and currently, no approved treatments exist. Preclinical studies indicate that JR-441 has the potential to mitigate CNS-related symptoms of MPS IIIA.

The open-label, multicenter, single-arm study focuses on evaluating the safety, biological impact, and pharmacokinetic profile of JR-441 in MPS IIIA patients aged 1 to under 18 years. Dr. Kimitoshi Nakamura, a Professor of Pediatrics at the Graduate School of Medical Sciences, Kumamoto University, and the study's Medical Expert, highlighted the significance of this trial. Dr. Nakamura emphasized the challenges MPS IIIA presents in treating CNS symptoms and expressed optimism about the new therapeutic approach. He hopes its effectiveness will be validated in the clinical setting, enhancing the lives of patients and their families.

JR-441 has obtained Orphan Drug Designation from both the European Commission (EC) and the U.S. Food and Drug Administration (FDA). Additionally, a Phase I/II trial commenced in Germany in 2023 (JR-441-101, NCT06095388).

For more information on the Japanese Phase I trial, visit the Clinical Research Submission and Disclosure System (JR-441-JP11, jRCT2071240053).

Mucopolysaccharidosis type IIIA, or Sanfilippo syndrome type A, is an autosomal recessive disorder caused by mutations in the SGSH gene. This gene encodes a lysosomal enzyme essential for degrading heparan sulfate. The accumulation of heparan sulfate in various body cells, especially in the CNS, leads to severe neurological decline, cognitive impairment, mild somatic issues, and a reduced lifespan.

JCR Pharmaceuticals Co., Ltd. (TSE 4552) is a global specialty pharmaceuticals company dedicated to expanding possibilities for individuals with rare and genetic diseases. With a 49-year legacy in Japan, JCR is extending its reach to the US, Europe, and Latin America. The company enhances patients' lives through scientific expertise and cutting-edge technology to research, develop, and deliver next-generation therapies. In Japan, JCR's approved products include treatments for growth disorders, MPS II (Hunter syndrome), Fabry disease, acute graft-versus-host disease, and renal anemia. Their investigational products under development globally target rare diseases such as MPS I (Hurler, Hurler-Scheie, and Scheie syndrome), MPS II, MPS IIIA and B (Sanfilippo syndrome types A and B), and others. JCR is committed to broadening patient possibilities and accelerating medical advancements worldwide. The company’s core values—reliability, confidence, and persistence—serve all stakeholders, including employees, partners, and patients.