A novel peptide drug candidate, jointly developed by the School of Life Sciences at The Chinese University of Hong Kong (CUHK) and its biotechnology spin-off company Rare Power Limited, has been granted Orphan Drug Designation by the U.S. Food and Drug Administration (FDA) for the treatment of Huntington\u2019s disease. The designation marks an important regulatory milestone in translating CUHK\u2019s deep-tech biomedical research into a disease-modifying therapy for this currently incurable, inherited neurodegenerative disorder. The research team is actively advancing preclinical development and aims to initiate first-in-human clinical trials within the next one to two years, bringing new hope to patients.<\/p>\r\n
Addressing an unmet need in Huntington\u2019s disease treatment<\/strong><\/p>\r\n Huntington\u2019s disease is a rare, autosomal-dominant neurodegenerative disorder caused by an expanded CAG trinucleotide repeat in the huntingtin<\/em> (HTT<\/em>) gene, causing progressive motor impairment (including chorea), psychiatric symptoms and cognitive decline. Symptoms typically emerge in mid-adulthood and worsen over time, ultimately leading to death. Current treatments are primarily symptomatic, for example, reducing chorea. However, no approved medicine directly targets the cause of the disease or effectively halts or slows its progression. The peptide drug candidate developed by CUHK and Rare Power seeks to address this major unmet medical need.<\/p>\r\n A breakthrough mechanism targeting disease at the source<\/strong><\/p>\r\n Listed in the FDA Orphan Drug Designations and Approvals database under the generic name \u201c21-amino acid peptide targeting expanded CAG repeat RNA\u201d, the CUHK-developed candidate introduces a novel therapeutic approach. Instead of focusing on lowering mutant huntingtin protein or its messenger RNA through gene silencing or related methods, the CUHK-Rare Power team treats the expanded CAG-repeat RNA itself as a pathogenic species. This structurally abnormal RNA can cause neurotoxicity and can also be translated into toxic protein. The team uses a peptide to bind that RNA, neutralising both the RNA and the toxicity that follows. The lead candidate is a 21-amino-acid peptide designed for this target. It has two distinctive features. First, the drug target is toxic, structurally abnormal RNA rather than mutant huntingtin protein. Second, the peptide recognises the folded structure of the expanded repeat RNA, unlike conventional small-molecule or nucleic-acid drugs.<\/p>\r\n Pre-clinical development advancing, with a first-in-human study targeted in one to two years<\/strong><\/p>\r\n Dr Maggie Leong Lok-i<\/strong>, co-founder and Chief Technological Officer of Rare Power Limited, said: \u201cThe candidate was built with an RNA structure-based drug design approach coupled with a tailor-made peptide engineering strategy. We designed the peptide to recognise the structural features of expanded CAG-repeat RNA rather than relying on a conventional small-molecule screen alone. Targeting the toxic RNA with a purpose-built peptide is a novel therapeutic concept for this disease. When we tested the candidate in patient-derived neurons, we saw promising activity against those RNA species. Our laboratory results, together with the FDA designation, give us a clear technical basis to take the molecule forward.\u201d<\/p>\r\n Professor Edwin Chan Ho-yin<\/strong>, Director of the School of Life Sciences at CUHK and co-founder of Rare Power Limited, said: \u201cOrphan designation recognises that our drug development programme addresses a genuine rare-disease need, and that defines a new class of RNA-targeted peptide as a product in the eyes of a regulator. Our next task is pre-clinical development in the disciplined sense: manufacturing quality, safety and long-term toxicology in large animals, so that we are prepared for a first-in-human study in about one to two years. CUHK will continue to fortify the scientific foundation of the programme, while Rare Power, with TSSSU and Incu-Bio Programmes\u2019 support, will carry that science through the industrial steps required for clinical translation. Patients with Huntington\u2019s disease have waited long enough for a disease-directed option. We intend to move forward with both urgency and scientific discipline.\u201d<\/p>\r\n About Rare Power Limited<\/strong><\/p>\r\n Rare Power was founded in 2023 as a CUHK-spinoff biotechnology company focused on developing peptides against short tandem repeat rare neurodegenerative diseases, including Huntington\u2019s disease, spinocerebellar ataxias and C9ORF72 ALS\/FTD. It is supported by the Innovation and Technology Commission\u2019s Technology Start-up Support Scheme for Universities (TSSSU) and is a member of the Hong Kong Science and Technology Parks Corporation (HKSTP) Incu-Bio Programme.<\/p>\r\n About FDA Orphan Drug Designation<\/strong><\/p>\r\n The FDA\u2019s Orphan Drug Designation is a regulatory status granted to investigational products intended for the treatment of rare diseases. Given small patient populations, prohibitive development costs, and limited commercial returns, many potential therapies for rare diseases face significant development challenges. As a result, such medicines are often regarded as therapeutic endeavours \u201cleft unclaimed\u201d. The Orphan Drug Designation status provides a range of development incentives, including regulatory guidance, certain fee waivers at later stages and potential qualifying eligibility for seven years of market exclusivity in the United States upon regulatory approval, accelerating the development and translation of novel therapies for patients.<\/p>\r\n