The Swiss regulatory authority has cleared StemCells to start a Phase I/II trial with its HuCNS-SC® (purified human neural stem cells) therapy in patients with spinal cord injury (SCI). The trial will include 12 patients with thoracic spinal cord injury, including those with both complete and incomplete injuries, classified as American Spinal Injury Association (ASIA) A, B, or C.
Primarily concerned with safety, the trial will, in addition, evaluate preliminary efficacy using defined clinical endpoints. Patient enrollment is expected to start during early 2011, and treated patients will receive HuCNS-SC through direct transplantation into the spinal cord alongside temporary immunosuppression. The study will evaluate participants over a 12-month period.
StemCells claims the trial of HuCNS-SC in SCI patients is the world’s first neural stem cell trial in this patient population. “This trial marks a significant broadening of our clinical development program,” comments Martin McGlynn, president and CEO at StemCells. “With this authorization we will soon have three active clinical trials evaluating our HuCNS-SC cells in conditions affecting both the brain and spinal cord.”
StemCells’ therapeutic programs are focused on the transplantation of tissue-derived adult stem cells and progenitor cells. The firm’s lead HuCNS-SC human neural stem cell program is already in clinical development for the treatment of the myelination disorder Pelizaeus-Merzbacher disese (PMD) and the lysosomal storage disorder neuronal ceroid lipofuscinosis (NCL, or Batten disease). Both these conditions are fatal neurodegenerative disorders that primarily affect young children.
The HuCNS-SC therapy is separately in preclinical development for the treatment of retinal disorders including age-related macular degeneration and at the research phase of development for Alzheimer disease and stroke.
Although the primary NCL and PMD disease targets for the HuCNS-SC technology are both rare conditions, StemCells hopes they will expedite development of the stem cell therapy for a broad range of CNS diseases and disorders. For example, it suggests that demonstrating a therapeutic benefit in NCL could lead to future treatments for more than 20 CNS-mediated lysosomal storage disorders that cannot be treated with enzyme-replacement therapy because the enzymes are too large to cross the blood-brain barrier.
In addition to its HuCNS-SC product, StemCells is progressing a liver program focused on the development of ihLEC™ human liver engrafting cells as a treatment for a range of liver diseases and initially liver-based metabolic disorders. The firm says the hLEC product candidate is enriched for progenitor cells, is directly transplantable, and exhibits the key characteristics required for a potential cell-based therapeutic, including long-term engraftment in vivo. It is separately evaluating an hLEC assay for toxicology screening of drug candidates.
News of approval to start a new trial with HuCNS-SC comes just 24 hours after StemCells announced the launch of three new human-specific mouse monoclonal antibodies, STEM101™, STEM121™, and STEM123™, designed to allow the visualization of human cells including human stem cells and their progeny. The firm claims the antibodies can be used to detect the engraftment, migration, and differentiation of human neural stem cells and human liver engrafting cells transplanted into rodents.
STEM101 recognizes the Ku80 protein found in human nuclei, STEM121 recognizes a cytoplasmic protein of human cells, and STEM123 recognizes human glial fibrillary acidic protein (GFAP). The new antibodies are the latest additions to the company's growing SC Proven® portfolio of research products.
Over recent months a number of firms have claimed "world’s firsts" with respect to clinical trials of stem cell therapies. While StemCells says its new HuCNS-SC trial in SCI is the world’s first neural stem cell trial in this patient population, just last month ReNeuron reported that it had started the world’s first fully regulated trial evaluating neural stem cells in stroke patients. This study is based on ReNeuron’s lead ReN001 product, which comprises a neural cell line, CTX, generated using the firm’s cell expansion and cell-selection technologies and and taken through full manufacturing scale-up.
The ReNeuron announcement was itself preceded in July by FDA lifting a prior clinical hold that means Geron will be able to start what it calls the world’s first human trial with a human embryonic stem cell therapy. The firm’s oligodendrocyte progenitor cell therapy GRNOPC1 will be evaluated in patients with complete ASIA-scale grade A subacute thoracic spinal cord injuries.