BEIJING – Canbridge Pharmaceuticals Inc. last week won marketing approval in China for its first rare disease drug, the mucopolysaccharidosis II (MPS II) therapy Hunterase (idursulfase beta injection). The win arrived just a day after it expanded its partnership with the University of Massachusetts Medical School to strengthen R&D efforts in gene therapy with an aim to expand its pipeline. The moves further consolidated the company’s rare diseases presence in China.
Hunterase, an enzyme replacement therapy, won approval for the long-term treatment of patients with MPS II, also known as Hunter syndrome. In doing so, it became the first NMPA-cleared enzyme replacement therapy for the indication in China.
“We plan to launch it soon, with priority given to provinces in which there is a reimbursement system already established for rare disease drugs,” Canbridge’s CEO James Xue told BioWorld. “In the meantime, we are working with MPS stakeholders toward the creation of similar mechanisms to cover all patients on the national level,”
Hunterase was developed by Korean firm GC Pharma Corp. In January 2019, Canbridge in-licensed rights to commercialize the drug in greater China, submitting an NDA to the NMPA six months later. The therapy is designated as an orphan drug in the U.S. and Korea and is currently marketed in 11 countries.
“The Hunterase approval is based on global clinical studies data, of which one of them is ongoing phase III study in South Korea, which includes Chinese MPS II patients,” said Xue.
A notable first
The approval of China’s first MPS II drug is a milestone. A recent study showed that 41% of patients with MPS in China did not receive any treatment after diagnosis, while 47% of them were only treated symptomatically due to a lack of enzyme replacement therapy in the country. As a result, 29 MPS II patients went to South Korea through a program of the Beijing Zhengyu Mucopolysaccharide Rare Disease Care Center to participate in the clinical trials for Hunterase, which led to the China approval last week.
MPS is one of 121 diseases on China’s 2018 national rare disease list, the country’s first official effort to recognize and define rare diseases. Industry experts believe the list will encourage the R&D of orphan drugs and speed up their marketing in China. It could also make those drugs more affordable for patients as it will serve as a reference for medical insurers and charities.
Canbridge’s efforts to advance orphan drugs are in alignment with China’s determination to help its rare disease patients. And, since orphan medicines are given priority reviews and speedy approvals under the regulators’ remit, there is a notable tailwind for companies like Canbridge that focus on rare disease.
“The Chinese market is warming up to rare disease drugs. Awareness is clearly spreading from the patient and physician level to the policy makers, with rare disease language and lists officially being written into law,” Xue told BioWorld in a previous interview.
“The aggressive price negotiations that government officials have been performing for the National Reimbursement Drug List is a sign that they are making room for diseases currently completely uncovered,” he said. “These are the elements that are moving gradually into place that will allow us to hope and plan for a reimbursed rare disease market.”
An expanding portfolio
Hunterase marks the second marketing success for Canbridge, after its Nerlynx (neratinib) was approved in May for the extended adjuvant treatment of adult patients with early stage HER2-positive breast cancer following adjuvant trastuzumab-based therapy.
Canbridge remains focused on rare diseases and has five more assets in its rare disease portfolio. They include CAN-106 for multiple genetic disorders, CAN-103 and CAN-104 for lysosomal storage disorders, CAN-105 for hematologic diseases and CAN-107 for metabolic disorders, which are all in preclinical stage.
Xue said that the company will continue to develop commercial infrastructure and an innovative rare disease portfolio in China, from enzyme replacement therapies and antibodies to gene therapy.
In June, Canbridge announced a partnership with the Horae Gene Therapy Center at the University of Massachusetts (UMass) Medical School to conduct gene therapy research with a focus on neuromuscular conditions. The aim is to add new assets to the company’s rare disease portfolio.
Just a day before the Chinese approval of Hunterase, the company said it has expanded the collaboration with the center to further study how adeno-associated virus (AAV) vectors can play a role the treatment of neuromuscular diseases.
“We expect for this to be a long-term collaboration between us and UMass,” said Xue. “From this partnership, we hope to bring multiple gene therapy programs in neuromuscular rare diseases.”
If successful, the partnership will give Canbridge access to a next-generation gene therapy platform technology to treat neuromuscular diseases.
While some rare diseases can be treated by removing a patient’s cells, treating the cells outside the body and then reintroducing them back into the body, this is not possible with many rare diseases, as the affected cells cannot be removed and re-introduced effectively.
“To address these diseases, one needs a vector that can be safely administered directly to the patient and efficiently transduce the cells affected by the disease in the patient’s body,” Xue explained, adding that AAV could be a promising platform to build new therapies for rare diseases.
He said that the efficacy, cost and safety of AAV based vectors need to be improved for this technology to reach its full potential, hence the collaboration with researchers from the UMass.
Miguel Sena-Esteves, associate professor of neurology at UMass Medical School, will lead the collaborative program with Canbridge. He and his team have been working on high throughput techniques to enable what he called an “a la carte” approach to AAV capsid engineering in order to meet multiple performance characteristics.
“Developing new AAV capsids to address dosing and immunological limitations that have emerged from clinical trials is critical for the ultimate success of in vivo gene therapy to deliver safe transformative therapies,” said Sena-Esteves.
Earlier in February, Canbridge closed a $98 million series D financing round to expand its rare disease pipeline through internal development and external partnerships. The company is also considering an IPO in the next 12 to 24 months.