StemCells Inc. Announces the Commencement of Their Macular Degeneration Clinical Trial

Age-related macular degeneration or AMD is a disease of the retina (at the back of the eye) characterized by a loss of photoreceptors (rods and cones) from the central part of the retina (macula), where vision in the clearest. A degenerative retinal disease, AMD typically strikes adults in their 50s or early 60s, and insidiously progresses usually painlessly until it gradually destroys central vision. There are approximately 1.75 million Americans age 40 years and older with some form of AMD, and the disease continues to be the number one cause of irreversible vision loss among senior citizens in the United States with more than seven million at risk of developing AMD.

There are no cures for AMD, but laser treatments are available for some types of AMD. Laser photocoagulation can disperse fluid that has built up under the retina. Such AMD is called “wet” macular degeneration and only works in the treatment of 15/100 cases of AMD. Other treatments include injections of either Avastin, Macugen or Eylea into the eye to prevent the spread of blood vessels that crowd out photoreceptors.  Photodynamic therapy uses a drug called Visudyne that is injected into the arm and them activated by a laser one in the eye where it destroys meandering blood vessels that leak or proliferate across the retina.  Patients with “dry” macular degeneration, however, find themselves out of luck.

Into the breach comes a clinical study by StemCells Inc. to use their proprietary neural stem cell line to treat dry macular degeneration. This Phase I/II clinical trial has already enrolled and transplanted its first patient this week and more subjects will undoubtedly be enrolled later. This trial is designed to evaluate the safety and preliminary efficacy of StemCells Inc’s proprietary HuCNS-SC neural stem cell line as a treatment for dry AMD. The first patient in this clinical trial received their transplant at the Retina Foundation of the Southwest in Dallas, Texas, which is one of the leading independent vision research centers in the United States. Globally, AMD afflicts approximately 30 million people worldwide and is the leading cause of vision loss and blindness in people over 55 years of age.

In February 2012, StemCells Inc Company published preclinical data that clearly showed that HuCNS-SC cells protect host photoreceptors and preserve vision in the rats that are engineered to experience retinal degeneration. This rat strain (Royal College of Surgeons or RCS rats) are a very well-established animal model for retinal disease and has been used extensively to evaluate potential cell therapies. In these pre-clinical studies, the number of cone photoreceptors, which are responsible for central vision, did not decrease due to cell death, but instead remained constant over an extended period. These same rats that had HuCNS-SC cells transplanted into their retinas showed steady maintenance of their visual acuity and light sensitivity. In humans, degeneration of the cone photoreceptors accounts for the unique pattern of vision loss in dry AMD. These data were published in an international peer-reviewed journal known as the European Journal of Neuroscience.

“This trial signifies an exciting extension of our on-going clinical research with neural stem cells from disorders of the brain and spinal cord to now include the eye,” said Stephen Huhn, MD, FACS, FAAP, Vice President and Head of the CNS Program at StemCells, Inc. “Studies in the relevant animal model demonstrate that the Company’s neural stem cells preserve vision in animals that would otherwise go blind and support the therapeutic potential of the cells to halt retinal degeneration. Unlike others in the field, we are looking to intervene early in the course of the disease with the goal of preserving visual function before it is lost.”

David G. Birch, Ph.D., Chief Scientific and Executive Officer of the RFSW and Director of the Rose-Silverthorne Retinal Degenerations Laboratory and principal investigator of the study, added, “We are excited to be working with Stem Cells [Inc.} on this ground breaking clinical trial. There currently are no effective treatments for dry AMD, which is the most common form of the disease, and there is a clear need to explore novel therapeutic approaches.”

StemCells, Inc. Human Neural Stem Cells Restore Memory in Models of Alzheimer’s Disease

StemCells, Inc., a Newark, California-based company has announced preclinical data that demonstrates that its proprietary human neural stem cell line restored memory and enhanced synaptic function in two animal models that are relevant to Alzheimer’s disease (AD). They presented these data at the Alzheimer’s Association International Conference 2012 in Vancouver, Canada.

In this study, neuroscientists from University of California, Irvine transplanted a neural stem cell line called HuCNS-SC, a proprietary stem cell line made by StemCells and is a purified human neural stem cell line, into a specific region of the brain, the hippocampus in laboratory animals. These injections improved the memories of two different types of laboratory animal that act as AD-significant models. The hippocampus is a portion of the brain that is critically important to the control of memory, and unfortunately, it is severely affected by AD. Specifically, hippocampal synaptic density is reduced in AD and these reductions in synaptic connections are highly correlated with memory loss. After injections of HuCNS-SCs, the animals showed increased synaptic density and improved memory after the cells had been transplanted. Importantly, these results did not require reduction in beta amyloid or tau that accumulate in the brains of patients with AD and account for the pathological hallmarks of the disease.

This research study resulted from collaboration between Frank LaFerla, Ph.D., who is the Director of the University of California, Irvine (UCI) Institute for Memory Impairments and Neurological Disorders (UCI MIND), and Chancellor’s Professor, Neurobiology and Behavior in the School of Biological Sciences at UCI, and Matthew Blurton-Jones, Ph.D., Assistant Professor, Neurobiology and Behavior at UCI.

“This is the first time human neural stem cells have been shown to have a significant effect on memory,” said Dr. LaFerla. “While AD is a diffuse disorder, the data suggest that transplanting these cells into the hippocampus might well benefit patients with Alzheimer’s. We believe the outcomes in these two animal models provide strong rationale to study this approach in the clinic and we wish to thank the California Institute of Regenerative Medicine for the support it has given this promising research.”

Stephen Huhn, M.D., FACS, FAAP, Vice President and Head of the CNS Program at StemCells Inc, added, “While reducing beta amyloid and tau burden is a major focus in AD research, our data is intriguing because we obtained improved memory without a reduction in either of these pathologies. AD is a complex and challenging disorder. The field would benefit from the pursuit of a diverse range of treatment approaches and our neural stem cells now appear to offer a unique and viable contribution in the battle against this devastating disease.”

Stem Cells Inc. Reports Positive Safety Data in Their Spinal Cord Injury Trial With Human Neural Stem Cells

StemCells, Inc., a biotechnology company based in Newark, California, has reported the results of their initial safety review of their human purified neural stem cell line implantations. This report represents the first planned interim safety review of the Company’s Phase I/II spinal cord injury clinical trial. This clinical trial involved a surgical implantation of the stem cells, and suppression of the immune system with anti-rejection drugs. The results of the safety trial show that both parts of the procedures seem to be well tolerated.

This trial was designed to determine the safety and potential, efficacy of the StemCells, Inc. proprietary HuCNS-SC® cells in spinal cord injury patients. HuCNS-SC cells are a purified human neural stem cell line that can form all the cells of the central nervous system (Taupin P. Curr Opin Mol Ther. 2006;8(2):156-63). When these cells are implanted into the retinas for rats that are suffering from retinal degeneration, they form a variety of retinal-specific cell types and seem to aid in retinal regeneration (McGill TJ., et al., Eur J Neurosci. 2012;35(3):468-77).

This clinical trial represents the first time that human neural stem cells have been implanted into the spinal cords of human patients as a potential therapeutic agent for spinal cord injury. The interim data come from the first cohort of patients. All of these first cohort patients suffered a complete spinal cord injury, and show no neurological function below the level of the injury.

All patients in the trial were transplanted with 20 million neural stem cells at the site of injury in the thoracic spinal cord. Observation of the patients revealed that there were no detectable abnormal responses to the cells, and all the patients were neurologically stable through the first four months following transplantation of the cells. Changes in sensitivity to touch were observed in two of the patients. These data merit the continuance of the trial, and further enrollments. Patients with partial spinal cord injuries, who might experience a broader range of improvements are also being sought for enrollment.

Armin Curt, M.D., principal investigator for the clinical trial, said, “We are very encouraged by the interim safety outcomes for the first cohort.”  Dr. Curt is Professor and Chairman of the Spinal Cord Injury Center at the University of Zurich, and Medical Director of the Paraplegic Center at Balgrist University Hospital. Dr. Curt continued, “The patients in the trial are being closely monitored and undergo frequent clinical examinations, radiological assessments by MRI and sophisticated electrophysiology testing of spinal cord function. The comprehensive battery of tests provides important safety data and is very reassuring as we progress to the next stage of the trial.”

StemCells, Inc. Announces Positive Preclinical Data for Its Human Neural Stem Cells Ability to Preserve Vision

A research team led by Raymond Lund, Ph.D., Professor Emeritus of Ophthalmology, and Trevor McGill, Ph.D., Research Assistant Professor at the Casey Eye Institute, Oregon Health and Science University have made a remarkable discovery using proprietary stem cells from StemCells, Inc. These results await publication in the European Journal of Neuroscience, and constitute positive preclinical data for StemCells, Inc. proprietary Human Central Nervous System Stem Cells (HuCNS-SC).

For these experiments, the team used Royal College of Surgeons (RSC) rats. RCS rats have an inherited form of retinal degeneration. Although the genetic defect that causes retinal regeneration was not known for many years, it was identified in the year 2000 to be due to a mutation in the Merkt gene. Mutations in the Merkt gene prevent the retinal pigment epithelium cells from scooping up outer segments of photoreceptor cells. As photoreceptor cells respond to light, their outer membrane proteins suffer photo-oxidation. Retinal pigment epithelial cells phagocytose these defective photoreceptor outer membrane segments and recycle them, which maintains photoreceptor health and function. When retinal pigment epithelium cells are unable to phagocytose photoreceptor out membrane segments, the photoreceptors accumulate photo-damage and eventually die.

To test the efficacy of HuCNS-SCs in preserving photoreceptor health, Lund and his colleagues injected HuCNS-SCs into the subretinal space of 21-day old RCS rats. They found that photoreceptors, the key cells of the eye involved in vision were protected from degeneration. Additionally, the density of healthy cone photoreceptors (those photoreceptors that help in color perception) remained relatively constant over several months. Visual acuity and luminance sensitivity tests in the injected RCS rats further corroborated the results of observed in the retinas. Apparently, the donor cells remained immature and did not differentiate throughout the seven-month experiment. However, the transplanted HuCNS-SCs underwent very little proliferation, and produced no tumors or abnormal growths. The ability of these transplanted cells to protect photoreceptors and preserve vision when injected into the retinas of RCS rats is important to human disorders of vision loss such as dry age-related macular degeneration (AMD).

Lund excitedly noted: “These results are the most robust shown to date in this animal model. One of the more striking findings is that the effect on vision was long-lasting and correlated with the survival of HuCNS-SC cells more than seven months after transplantation, which is substantially longer than other cell types transplanted into this same model. Also important, particularly for potential clinical application was that the cells spread from the site of initial application to cover more of the retina over time. These data suggest that HuCNS-SC cells appear to be a well-suited candidate for cell therapy in retinal degenerative conditions.”

Another investigator in this study, Alexandra Capela, Ph.D., a senior scientist at StemCells, commented, “This study showed that the HuCNS-SC cells persisted and migrated throughout the retina, with no evidence of abnormal cell formation, which supports our hypothesis of a single transplant therapeutic. With this research, then, we have shown that vision can be positively impacted with a simple approach that does not require replacing photoreceptors or the RPE cells. We look forward to investigating this promising approach in the clinic later this year.”