Many modalities are being evaluated for the treatment of retinal degenerative diseases such as retinitis pigmentosa (RP), including stem cell therapy where dead or damaged cells are replaced by healthy ones.

In the summer of 2022, Endogena launched its first dosing of its phase 1/2a study of EA-2353 in retinitis pigmentosa (RP).

Researchers at the University of Wisconsin-Madison have been working with stem cells to grow organoids in a petri dish that resemble the retina.

Researchers used stem cells from an individual with retinitis pigmentosa (RP) caused by mutations in their USH2A gene to create retinal organoids (ROs), that mimics the retina to be used as an in vitro RP disease model.

Research is being conducted at the University of Pennsylvania School of Veterinary Medicine, with the University of Wisconsin, Children's Hospital of Philadelphia and the National Institutes of Health’s National Eye Institute for a cell therapy for people with retinal disorders.

A team of researchers from Germany's Center for Regenerative Therapies Dresden (CRTD) reported positive results in their pre-clinical studies where lab-grown human photoreceptor cells (cones) were transplanted into mice with damaged cones.

At the University of Wisconsin-Madison, researchers are studying stem cells and how they could potentially treat retinal diseases, including retinitis pigmentosa and Usher syndrome.

Researchers at the University of Wisconsin School of Medicine and Public Health were able to create retinal cells from human stem cells that can detect light and change it to electrical waves.

Researchers in China successfully created an induced-pluripotent stem (iPS) cell line using immune cells from the blood of a patient with Usher syndrome type 2A.

Researchers at Newcastle University are looking into creating treatments for common inherited eye conditions.

A recent biotechnology breakthrough is the organ-on-chip (OOC) technology.

AIVITA Biomedical Inc., a biotech company that specializes in new ways of using stem cells, recently conducted a preclinical study. Using human stem cells that they created, researchers created and tested a “total retina patch” for vision loss.

Researchers have been exploring stem cell therapies to treat vision loss, including vision loss caused by retinitis pigmentosa. Preclinical and clinical studies are showing that stem cell therapies could be new options.

A Phase 2 clinical trial was used to see if injecting human retinal progenitor cells (derived from stem cells) can improve vision and visual fields in people with retinitis pigmentosa (RP).

Individuals that have permanent damage to their photoreceptors are unable to repair or regenerate new photoreceptors. Researchers and engineers may have a possible solution for these individuals living with vision loss. They have worked to make new photoreceptors and a micro-molded scaffolding photoreceptor “patch.”

Magdalene Seiler, Ph.D., UCI associate professor has been awarded a five-year grant of $3,823,950 from the National Institutes of Health to do a preclinical study using rodent models. This study looks at an innovative co-graft method to permanently repair damaged retinas.

Photoreceptor precursor cells that were generated from stem cells were able to be successfully transplanted into the retina and demonstrate basic visual function.

In a recent study, retinal cells coming from adult human eye stem cells were successfully put into the eyes of monkeys.

An interdisciplinary team of scientists funded by University of Toronto’s Medicine by Design initiative believes they can improve the outcomes of conditions like age-related macular degeneration and retinitis pigmentosa.

Journalists at Fierce Biotech summarized exciting research from the Centre for Genomic Regulation in Barcelona. They are studying how stem cell biotechnology can be improved in retina disease treatment models.

Lentivirally modified mesenchymal stem cells from bone marrow shows promise in preserving retinal function and preventing further retinal degradation.

Intravitreal injection of human retinal progenitor cells (hRPCs;jCells) is a novel stem cell treatment currently in development for retinitis pigmentosa (RP. In a recently completed phase 2b study, this treatment was injected into the jelly-like center or vitreous of the eye and has demonstrated promising biologic activity and an excellent safety profile. In this study, 84 patients diagnosed with RP and with best-corrected visual acuity (BCVA) between 20/80 to 20/800 were randomly assigned to 2 different doses (low or high) of jCells or a placebo. The primary end point (or target outcome) was the mean change in the BCVA at 12 months; the secondary end points were identification of the lowest light level at which patients could navigate through a structured mobility maze, along with the mapping of each patient’s kinetic visual field, the evaluation of their performance on contrast sensitivity testing, and completion of a low vision–specific quality-of-life questionnaire. In a post hoc analysis of this target population, an early and significant improvement in vision was seen in the higher-dose group, with average gain of 16 letters at month 12 compared with 2 letters in the control group. Improvement in the higher-dose group compared to the control group was also true for the secondary outcomes. While there were some mild cases of eye inflammation and one severe case of hypertension associated with treatment, these adverse effects were addressed. These study results showed that intravitreal injection of allogeneic jCells that were not derived directly from the patient shows promising results. The study is expected to continue with expected redosing of patients and further monitoring as this treatment is not expected to be permanent.

What this means for Usher syndrome: These results from a Phase 2b study demonstrate that intravitreal injection of retinal progenitor stem cells shows measurable improvement in vision and may be a viable treatment option in the future for both Usher and RP patients.

Researchers have discovered a technique for directly reprogramming skin cells into light-sensing rod photoreceptors used for vision. The laboratory-made rods enabled blind mice to detect light after the cells were transplanted into the animals’ eyes. According to Anand Swaroop Ph.D., senior investigator, “This is the first study to show that direct, chemical reprogramming can produce retinal-like cells, which gives us a new and faster strategy for developing therapies for age-related macular degeneration and other retinal disorders caused by the loss of photoreceptors.” The immediate benefit of this technique will be the ability to develop models to allow us to study the mechanisms of the disease and design better cell replacement approaches. Induced pluripotent stem (IPS) cells take about six months to create, however direct reprogramming takes only about ten days to convert skin cells into functional photoreceptors. A clinical trial to test the therapy in humans for degenerative rental diseases such as retinitis pigmentosa is in the works.

What this means for Usher syndrome: This new technique holds promise for treatment of many retinal degenerative diseases, including Usher syndrome.

Stem cell technology has enabled new possibilities for understanding and treating rare diseases such as Usher syndrome. The technology for stem cell treatment is still relatively new and complex. Unfortunately, several private clinics are attempting to financially capitalize on patients’ desperation and confusion for a cure. David Gamm, MD, PhD, a researcher at the University of Wisconsin-Madison, wrote an article for Foundation Fighting Blindness explaining the ten things we should know before falling victim to a retinal stem cell scam. Even if the treatment does not cause physical harm, it can result in significant financial damage; therefore, it is important to be aware of these scams.

The ReNeuron Group has announced positive long-term data from its ongoing phase 1/2a clinical trial of its hRPC (human retinal progenitor cells) stem cell therapy candidate in Retinitis Pigmentosa. In October 2019 at the American Academy of Ophthalmology Meeting in San Francisco, data presented by Pravin Dugel, MD showed “a group of subjects who had a successful surgical procedure with sustained clinically relevant improvements in visual acuity compared with baseline, as measured by the number of letters read on the ETDRS chart.” The company has submitted a protocol amendment to the FDA to expand their 1/2a study to treat up to a further nine patients in the phase 2a segment of the study with a dose of two million hRPC cells compared to the dose of one million cells used so far. The amended trial protocol allows for a greater range of pre-treatment baseline visual acuity in patients and includes changes that enhance the ability to use microperimetry testing to measure and detect changes in retinal sensitivity in patients treated. If the amendment is approved the company expects to have sufficient data to commence a pivotal clinical study with its hRPC cell therapy candidate in RP by 2021. Furthermore, this clinical program has been granted Orphan Drug Designation in Europe and the US, as well as Fast Track designation from the FDA.

What this means for Usher syndrome:That Usher patients may benefit from this stem cell therapy in the near future if the amendment is approved and the company obtain sufficient data for the initiation of the pivotal clinical trial .

The aim of this study is to determine if umbilical cord Wharton’s jelly derived mesenchymal stem cells implanted in sub-tenon space have beneficial effects on visual functions in RP patients by reactivating the degenerated photoreceptors in dormant phase. 32 RP patients participated in the study and were followed for 6 months after the Wharton’s jelly derived mesenchymal stem cell administration. Regardless of the type of genetic mutation, sub-tenon Wharton's jelly derived mesenchymal stem cell administration appears to be an effective and safe option. There are no serious adverse events or ophthalmic / systemic side effects for 6 months follow-up. Although the long-term adverse effects are still unknown, as an extraocular approach, subtenon implantation of the stem cells seems to be a reasonable way to avoid the devastating side effects of intravitreal/submacular injection.

What this means for Usher syndrome: If successful, this stem cell therapy will help Usher patients to recover their vision while minimizing the invasive adverse effects of the treatment.

Researchers at the National Eye Institute are launching a clinical trial to test the safety of a novel patient-specific stem cell-based therapy to treat geographic atrophy, the advanced “dry” form of age-related macular degeneration (AMD), a leading cause of vision loss among people age 65 and older. This is the first clinical trial in the USA to utilize replacement tissues from patient-derived induced pluripotent stem cells (iPSC). Under the phase I/IIa clinical trial protocol, 12 patients with advanced-stage geographic atrophy will receive the iPSC-derived RPE implant in one of their eyes. The patients will be closely monitored for at least one year to confirm safety.

What this means for Usher syndrome: This trial could pave the way to stem cell treatments of other eye diseases, including Usher syndrome.

Cedars-Sinai, a non-profit healthcare organization based in Los Angeles, has received authorization from the FDA to launch a 16-person, Phase 1/2a clinical trial of human neural progenitor cells—stem cells that have almost developed into neural cells—for patients with retinitis pigmentosa (RP). The trial will be launched after investigators receive the final institutional review of the study protocol. The trial is being funded by a $10.5 million grant from the California Institute for Regenerative Medicine. The initial study was conducted by Dr. Shaomei Wang, MD, PhD, a professor of Biomedical Sciences and a research scientist in the Eye Program at the Board of Governors Regenerative Medicine Institute. He showed that human neural progenitor cells have the potential to treat RP. The clinical trial will be directed by Dr. Clive Svendsen, PhD, professor of Biomedical Sciences and Medicine and director the Cedars-Sinai Board of Governors Regenerative Medicine Institute. Dr. David Lao, MD, from Retina-Vitreous Associates Medical Group in Beverly Hill, will be responsible for the subretinal injection of the cells into patients. The ultimate goal of this therapy is to restore the vision by replacing the defective photoreceptors.

What this means for Usher syndrome: This means that more potential stem-cell based treatments are becoming available to treat Usher patients. Since photoreceptors are the main cell group affected in Usher syndrome, the possibility of successfully replacing them with healthy cells give hope to patients that are losing their sight. Still we need to be careful and wait for the results of this new clinical trial.

Researchers in Germany have recently developed a “retina-on-a-chip” which combines living human cells with an artificial tissue-like system. The scientists describe their work as “merging organoid and organ-on-a-chip technology to generate complex multi-layer tissue models in a human Retina-on-a-Chip platform.” Ophthalmologic drugs largely rely on animal models, which often do not provide results that are translatable to human patients. In this study, researchers present the retina-on-a-chip (RoC), a novel microphysiological model of the human retina integrating more than seven different essential retinal cell-types derived from human induced pluripotent stem cells (hiPSCs).

What this means for Usher syndrome: this model can be used to test hundreds of drugs for harmful effects on the “human” retina very quickly and enables scientists to take stem cells from a specific patient and study both the disease and potential treatment in the individual’s own cells.

To develop biological approaches to restore vision, scientists developed a method of transplanting stem cell-derived retinal tissue into the retina of an animal model, a cat. Human embryonic stem cells were successfully grafted into the retina of cats. The researchers observed strong infiltration of immune cells into the graft and surrounding tissue in the cats treated with prednisolone alone. The cats treated with prednisolone plus cyclosporine A showed better survival and low immune response to the grafts. This work demonstrates the feasibility of engrafting human embryonic stem cell-derived retinal tissue into the retina of large-eye animal models. Transplanting retinal tissue in degenerating cat retina will enable rapid development of preclinical work focused on vision restoration.

What this means for Usher syndrome: This procedure may provide a platform for testing stem cell-based therapies to treat Usher syndrome patients.

ReNeuron Group plc has announced the latest updated positive preliminary results in the company’s ongoing phase 1 and 2a clinical trial of its human retinal progenitor cell (hRPC) therapy candidate in retinitis pigmentosa. All three subjects in the first group of phase 2a have demonstrated a sustained and further improvement in vision compared to their pre-treatment baseline.

What this means for Usher syndrome: This potential therapy could provide a means to restore lost vision in Usher syndrome patients.

Stem cells are cells that have the capability of becoming any type of cells in an organism and in the right environment. Researchers are trying to use stem cell therapy to replace lost photoreceptors and preserve residual photoreceptors during retinal degeneration. One of the problems is that the degenerative microenvironment that already exists in the diseased retina compromises the fate of grafted cells. The desired donor cells will need to have both proper regenerative capability and the ability to improve their own microenvironment. For this purpose, the authors of the present work used specific cell surface molecules that help to kill tumorigenic embryonic cells and at the same time enrich retinal progenitor cells. The retinal progenitors were obtained from embryonic stem cells derived from retinal organoids (three dimensional structures derived from pluripotent cells) that were grafted into retinal degeneration rat and mouse models. After three months post-treatment, those animals showed a 40% increase in healthy photoreceptor cells and a decrease in inflammatory molecules, demonstrating the importance of a healthier environment for the grafted cells.

What this means for Usher syndrome: These two features of the organoid systems, regenerative capability and generation of a healthier microenvironment, will, very likely, benefit Usher patients as an additional therapy to delay or prevent photoreceptor loss.

ReNeuron Group, a UK-based global leader in the development of cell-based therapeutics, announced positive preliminary results in the company’s ongoing Phase 1/2 clinical trial of its human retinal progenitor cells candidate therapy for the blindness-causing disease, retinitis pigmentosa (RP). All three subjects in the first group of the Phase 2 part of the trial demonstrated a significant improvement in vision at the follow-up compared to their pre-treatment baseline and compared with their untreated control eye.

What this means for Usher syndrome: A similar cell-based therapy tailored to Usher syndrome may help restore vision.

A new purple protein, bacteriorhodopsin, has made its way from a tiny laboratory in Farmington, Connecticut, all the way up to the International Space Station. Since bacteriorhodopsin is light-sensitive, researchers hope to implant it into human eyes. The thought is that the protein could be used to replace cells that die due to diseases like retinitis pigmentosa and age-related macular degeneration. To simulate the cells, the laboratory in Farmington needs to build what it is called “organic implants” by layering the bacteriorhodopsin onto a film and dipping it over and over into a series of solutions. These solutions need to have a uniform distribution that can be adversely affected by gravity. To test this, LambdaVision has secured a spot for their experiment aboard the International Space Station, using funding from the ISS National Lab and Boeing.

What this means for Usher syndrome: These “organic implants”, composed of bacteriorhodopsin, could be capable of replacing dying photoreceptors in the retina.

Researchers revealed that culturing human induced pluripotent stem cells with different isoforms of the extracellular component laminin led to the creation of cells specific to different parts of the eye, including retinal, corneal, and neural crest cells. They showed that the different laminin variants affected the cells' motility, density, and interactions, resulting in their differentiation into specific ocular cell lineages. Cells cultured in this way could be used to treat various ocular diseases.

What this means for Usher syndrome: There is the possibility of replacing the photoreceptor cells that are dying in the retina with pluripotent cells that have been grown and induced into healthy photoreceptor cells.

Since 1995, University of California, Irvine stem cell researcher Magdalene J. Seiler, PhD has pursued promising research into the development and usage of retinal sheet transplantation. The treatment is based on transplanting sheets of stem cell-derived retina, called retina organoids to the back of the eye with hopes of re-establishing the neural circuity within the eye. Recently, Seiler has received a $4.8 million grant from the California Institute of Regenerative Medicine (CIRM) to continue to develop a stem cell-based therapy for retinal diseases such as retinitis pigmentosa.

A group of research physicians have discovered that using stem cells from a person’s own bone marrow has reported success in improving vision for patients with Retinitis Pigmentosa. The bone marrow stem cells come from the same person; therefore, there can be no rejection. Of the 33 eyes studied, 45.5% of individual eyes improved and 45.5% remained stable over the follow-up period when they typically have been worsening. Vision improvement is 98.4% likely to be a consequence of this treatment.

ReNeuron, a developer of cell-based therapeutics, received a $1.5 million grant award from the UK Innovations agency. The project will allow further development of cell banks of ReNeuron’s hRPC candidate and as well as the development of product release assays for late-stage clinical development. The hRPC therapy is currently being tested in a Phase III clinical trial in the US for patients suffering retinitis pigmentosa.

A retinal implant allowed a 69 year old woman with macular degeneration to see more than double the usual number of letters on the vision chart. Luxturna, the gene therapy was approved by the FDA in 2017, corrects a mutation found in Leber congential amaurosis (LCA).

This story is designed to help you find an answer to the question: will a stem cell therapy work for me? To get an answer, Dr. Mary Sunderland of the Foundation Fighting Blindness Canada, suggests that you pay attention to three key points when you read new stories about stem cell discoveries or clinical trials...

A French biopharma company has announced their plans to carry out human trials of a new treatment that would insert genes from light-seeking algae into the eyes of patients with inherited blindness in order to help them regain sight. The treatment involves optogenetics, a technique that converts nerve cells into light sensitive cells.

jCyte, one of the leaders in developing cell-based therapies for RP, announces positive 12-month results from its Phase 1/2a clinical trial to treat retinitis pigmentosa with stem cells.

A plea to the Usher syndrome community: do not rely on testimonials and press releases to influence your medical treatment decisions.

Encouraging signs this week that the FDA is serious when it granted Regenerative Medicine Advanced Therapy (RMAT) status to the CIRM-funded jCyte clinical trial for a rare form of blindness. This is a big deal because RMAT seeks to accelerate approval for stem cell therapies that demonstrate they can help patients with unmet medical needs.

Foundation Fighting Blindness Press Release (Columbia, MD) - A Cautionary Tale About the Need to Educate Patients and Advance Research to Produce Treatments with Proven Efficacy, Says Foundation Fighting Blindness

Chimeras are incredibly useful for understanding how animals grow and develop. They might one day be used to grow life-saving organs that can be transplanted into humans.

Foundation Fighting Blindness' deputy chief research officer, Dr. Brian Mansfield, explains how retinal researchers are working with induced pluripotent stem cells (iPSC), a patient's own skin cells, to gain a better understanding of the RP caused by defects in the gene USH2A. This basic research provides critical information for developing future treatments.

Researchers at the University of Wisconsin-Madison developed an innovative process to transform skin cells into retinal cells — cells that hold great promise for restoring vision.

ReNeuron, a stem cell development company in the United Kingdom, is planning to file for regulatory approval in late 2013 to launch a clinical trial of a stem cell treatment for people with retinitis pigmentosa

Researchers in Japan have discovered a way to coax mouse embryonic stem cells into forming an eyelike structure.

For only the second time, the Food and Drug Administration approved a company’s request to test an embryonic stem cell-based therapy on human patients. Advanced Cell Technology (ACT), based in Marlborough, Mass., will begin testing its retinal cell treatment this year in a dozen patients with Stargardt’s macular dystrophy, an inherited degenerative eye disease that leads to blindness in children.

A new stem cell therapy is now available to eye patients using subretinal placement of adult stem cells. Initial patients included an individual with Stargardts Disease and a patient with Age Related Macular Degeneration.

UC Irvine researchers have created a retina from human embryonic stem cells, the first time they've been used to create a three-dimensional tissue structure. The eight-layer, early stage retina could be the first step towards the development of transplant-ready retinas to treat eye disorders, such as retinitis pigmentosa and macular degeneration.

A research team funded by the Foundation Fighting Blindness has used cell transplantation to restore vision in a mouse model of Usher syndrome type 2A. . Never before has a cell-based treatment been used to save vision in an Usher syndrome study, in large part because no other Usher syndrome animal models have exhibited vision loss or retinal degeneration. The advancement is a critical step forward in developing a vision treatment for humans with the condition.

An international research team led by Columbia Univ. Medical Center successfully used mouse embryonic stem cells to replace diseased retinal cells and restore sight in a mouse model of retinitis pigmentosa.

The man had Limbal Stem Cell Deficiency, which is not genetic, but the technology may be applicable to Usher patients in the future.

The transplantation of stem cells that are capable of producing functional cell types might be a promising treatment for hearing impairment.

This handbook on stem cell therapies was published in 2008 but is still very relevant today.

According to Reuters, stem cells from tiny embryos can be used to restore lost hearing and vision in animals. This research holds promise for humans.