Blindness Fact Sheet

CIRM funds many projects seeking to better understand diseases of blindness and to translate those discoveries into new therapies.


Over a million Americans are legally blind, with another 3.2 million suffering significant visual impairment1. While there are several causes of blindness, the leading cause of all visual impairment is age-related macular degeneration, which affects 1.7 million Americans. 

California’s stem cell agency funds research into potential therapies for three of the causes of blindness. All the research teams are seeking to use various forms of stem cells to rescue or replace cells in the eye damaged or threatened by the diseases. Several groups are working on ways to restore vision for people with age-related macular degeneration (AMD). Other projects are looking to preserve vision in patients with retinitis pigmentosa (RP), and to restore clarity to the surface of eyes impacted by corneal disease.

Macular Degeneration

AMD affects 8 million Americans and accounts for over 50% of vision loss cases in white Americans. In AMD, the layer of cells that support the photoreceptors is destroyed. Without this support system, the photoreceptors, the cells that actually allow us to sense light start to malfunction. CIRM-funded teams are looking at various methods of replacing this layer of support cells called RPE (retinal pigment epithelial) cells. Some are using embryonic stem cells as a starting point to generate new RPE cells. Others are using stem cells obtained by reprogramming adult cells to be like embryonic cells, which could potentially come from the patients’ themselves.

Retinitis Pigmentosa

Retinitis pigmentosa (RP) is an inherited and progressive vision loss disease that has an incidence of 1:4000 and leaves most patients legally blind by mid-life. RP destroys the light-sensing photoreceptors in the retina. CIRM-funded researchers are seeking to use stem cells to rescue these photoreceptors from further damage and potentially replace them with new ones.

Limbal Stem Cell Deficiency

The cornea, the outer surface of the eye, is constantly refreshed by stem cells that reside in neighboring tissue. But some people just don’t have enough of these stem cells, called limbal stem cells, to make enough new cornea cells. CIRM-funded researchers are trying to correct this condition, limbal stem cell deficiency, by retrieving the few existing limbal stem cells, and using various techniques to expand them in the laboratory until there are enough cells to rebuild a healthy cornea.

Clinical Stage Programs

University of Southern California

This team is using embryonic stem cells to produce the support cells, or RPE cells, needed to replace those lost in AMD. Because these cells exist in a thin sheet in the back of the eye, they are assembling these sheets in the lab by growing the RPE cells on synthetic scaffolds. These sheets are then surgically implanted into the eye. They are testing the human embryonic stem cell-derived RPE cells in a Phase 1/2a clinical trial to treat the advanced dry form of AMD. 

University of California, Los Angeles

This team, led by Sophie Deng, is taking the patient’s owns limbal stem cells and expanding their number in the laboratory, then returning them to the patient in the hope they will repair the damage caused by the disease and help restore vision or at least halt the progression of the disease.  They are testing this in a Phase 1 clinical trial. They are also using novel diagnostic methods to assess the severity of the disease and the patient’s response to treatment.

University of California, Irvine

For retinitis pigmentosa, the team is using donor tissue to isolate cells that are part way down the path from neural stem cells to adult eye tissue. These retinal progenitor cells are grown in large quantities in the lab and then injected into the eye. The team suggests the cells could help in two ways. They may be able to protect the photoreceptors not yet damaged by the disease, and they may be able to form new photoreceptors to replace those already lost. The team tested the safety of transplanting human retinal progenitor cells into patients with RP in a phase 1/2 clinical trial that is now completed. CIRM is now funding a Phase 2 trial, sponsored by a jCyte, that is testing this treatment in a larger group of RP patients (see trial below).


The same team from UC Irvine is now conducting a Phase 2b clinical trial for retinitis pigmentosa using the same stem cell derived retinal progenitor cell therapy. The trial, which is sponsored by the company jCyte, will test the treatment in a larger patient population to determine whether the treatment is effective at restoring some vision. After finishing patient enrollment, the team will conduct patient follow up studies and collect of all clinical outcome measures.

CIRM Grants Targeting Vision Loss

Researcher NameInstitutionGrant TitleGrant TypeAward Amount
Erik UllianUniversity of California, San FranciscoModeling Retinitis Pigmentosa using patient-derived human iPSC organoidsFoundation – Discovery Stage Research Projects$1,380,543
Cameron Keast BakerAdverum BiotechnologiesDevelopment of an Optogenetic Vision Restoration Gene Therapy Using an Engineered Form of MelanopsinQuest – Discovery Stage Research Projects$1,150,820
Dr. Xian-Jie YangUniversity of California, Los AngelesDeveloping gene therapy for dominant optic atrophy using human pluripotent stem cell-derived retinal organoid disease modelsQuest – Discovery Stage Research Projects$1,345,691
Dr. Jonathan H LinUniversity of California, San DiegoSmall Molecule Proteostasis Regulators to Treat Photoreceptor DiseasesQuest – Discovery Stage Research Projects$1,153,937
Karl Karl J. WahlinUniversity of California, San DiegoAn IPSC cell based model of macular degeneration for drug discovery.Inception – Discovery Stage Research Projects$232,200
Biju B. ThomasUniversity of Southern CaliforniaA Novel Tissue Engineering Technique to Repair Degenerated RetinaInception – Discovery Stage Research Projects$215,133
Jeffrey L GoldbergStanford UniversityEmbryonic Stem Cells for Corneal Endothelial DegenerationInception – Discovery Stage Research Projects$235,836
Karl Karl J. WahlinUniversity of California, San DiegoMicroenvironment based optimization of retinal induction using CRISPR-CAS9 reporter pluripotent stem cells as an expandable source of retinal progenitors and photoreceptors.Inception – Discovery Stage Research Projects$232,200
Paul BresgeRay Therapeutics, INCOptogenetic Therapy for Treatment of Geographic AtrophyTherapeutic Translational Research Projects$3,998,930
Anthony J AldaveUniversity of California, Los AngelesAAV Gene Therapy for Treating Congenital Hereditary Endothelial Dystrophy associated with Biallelic SLC4A11 MutationsTherapeutic Translational Research Projects$4,338,166
Dr. Sophie X DengUniversity of California, Los AngelesExtracellular Vesicle-Based Therapy for Corneal ScarsTherapeutic Translational Research Projects$5,779,276
Paul BresgeRay Therapeutics, INCOptogenetic therapy for treating retinitis pigmentosa and other inherited retinal diseasesTherapeutic Translational Research Projects$3,999,553
Dr. Mark S HumayunUniversity of Southern CaliforniaPRPE-SF, polarized hESC-derived RPE Soluble Factors, as a Therapy for Early Stage Dry Age-related Macular DegenerationTherapeutic Translational Research Projects$3,697,935
Dr. Theodore LengStanford UniversityNeuBright, a purified allogeneic cell therapy product for treatment of Dry Age-related Macular DegenerationTherapeutic Translational Research Projects$4,235,758
Steven SchwartzUniversity of California, Los AngelesClinical Translation of Autologous Regenerative Cell Therapy for BlindnessTherapeutic Translational Research Projects$5,068,026
Dr. Magdalene J SeilerUniversity of California, IrvineMorphological and functional integration of stem cell derived retina organoid sheets into degenerating retina modelsTherapeutic Translational Research Projects$4,769,039
Mark WisniewskiUniversity of California, Los AngelesLos Angeles Bioscience Ecosystem Summit Twenty 24 (LABEST 24)Conference II$50,000
Dr. Jeffrey H SternLuxa BiotechnologyRPESC-RPE-4W Therapy for dry Age-related Macular DegenerationClinical Trial Stage Projects$4,009,675
Dr Jane S LebkowskiRegenerative Patch Technologies LLCA Phase 2b, Randomized, Assessor-Masked Clinical Trial to Assess the Safety and Efficacy of the CPCB-RPE1 Implant in Subjects with Geographic AtrophyClinical Trial Stage Projects$12,373,748
R. Kim BrazzellCombangio, Inc.Phase 2b Clinical Study of KPI-012 Topical Ophthalmic Human Mesenchymal Stem Cell Secretome for the Treatment of Persistent Corneal Epithelial DefectClinical Trial Stage Projects$15,000,000
Dr Robert HayesImmusoft CorporationA Phase I Open Label Study to Evaluate the Safety and Tolerability of ISP-001 in Patients with Mucopolysaccharidosis Type 1Clinical Trial Stage Projects$8,000,000
Dr. Sophie X DengUniversity of California, Los AngelesSafety and Feasibility of Cultivated Autologous Limbal Stem Cells for Limbal Stem Cell DeficiencyClinical Trial Stage Projects$10,301,486
Clive SvendsenCedars-Sinai Medical CenterClinical Study to Assess Safety and Efficacy of Subretinal Injection of Human Neural Progenitor Cells for Treatment of Retinitis PigmentosaClinical Trial Stage Projects$10,444,063
Henry John KlassenjCyte, IncA Phase 2 Study of the Safety of Repeat Intravitreal Injection of Human Retinal Progenitor Cells (jCell) in Adult Subjects with Retinitis PigmentosaClinical Trial Stage Projects$5,175,000
Henry John KlassenjCyte, IncPhase 2b Clinical Study of Safety and Efficacy of Intravitreal Injection of Retinal Progenitor Cells (jCell) for Treatment of Retinitis PigmentosaClinical Trial Stage Projects$8,295,750
Dr. Jerome A. Zack Ph.D.University of California, Los AngelesClinical Translation of Autologous Regenerative Pluripotent Stem Cell Therapy for BlindnessLate Stage Preclinical Projects$6,000,000
Dr. Sophie X DengUniversity of California, Los AngelesRegeneration of a Normal Corneal Surface by Limbal Stem Cell TherapyLate Stage Preclinical Projects$4,244,211
Shaomei WangCedars-Sinai Medical CenterIND-enabling study of subretinal delivery of human neural progenitor cells for the treatment of retinitis pigmentosaLate Stage Preclinical Projects$4,954,514
Dr. David V. SchafferUniversity of California, BerkeleyEngineered Biomaterials for Scalable Manufacturing and High Viability Implantation of hPSC-Derived Cells to Treat Neurodegenerative DiseaseTools and Technologies III$1,239,276
Dr. Mark S HumayunUniversity of Southern CaliforniaStem cell based treatment strategy for Age-related Macular Degeneration (AMD)Disease Team Planning$3,088
Dr. Mark S HumayunUniversity of Southern CaliforniaPhase 1 Safety Assessment of CPCB-RPE1, hESC-derived RPE Cell Coated Parylene Membrane Implants, in Patients with Advanced Dry Age Related Macular DegenerationDisease Team Therapy Development III$16,339,827
Dr. Magdalene J SeilerUniversity of California, IrvineRestoring vision by sheet transplants of retinal progenitors and retinal pigment epithelium (RPE) derived from human embryonic stem cells (hESCs)Early Translational IV$3,998,948
Dr. Kang Zhang M.D.University of California, San DiegoGeneration of fibroblast cell lines in patients with common blinding eye diseasesTissue Collection for Disease Modeling$1,034,425
Deepak A LambaBuck Institute for Age Research3D Modeling of Retina using Polymer Scaffolds for Understanding Disease PathogenesisBasic Biology IV$1,212,553
Dr. Henry John KlassenUniversity of California, IrvineRetinal progenitor cells for treatment of retinitis pigmentosaDisease Team Therapy Development – Research$17,144,825
Dr. Sophie X DengUniversity of California, Los AngelesRegeneration of Functional Human Corneal Epithelial Progenitor CellsEarly Translational II$697,507
Dr. Sophie X DengUniversity of California, Los AngelesRegeneration of Functional Human Corneal Epithelial Progenitor CellsEarly Translational II$1,524,947
Dr. Henry John KlassenUniversity of California, IrvineHuman retinal progenitor cells as candidate therapy for retinitis pigmentosaEarly Translational II$1,803,768
Professor Peter J CoffeyUniversity of California, Santa BarbaraDevelopment of Cellular Therapies for Retinal DiseaseResearch Leadership$4,690,963
Dr. Martin FriedlanderScripps Research InstituteAutologous Retinal Pigmented Epithelial Cells Derived from Induced Pluripotent Stem Cells for the Treatment of Atrophic Age Related Macular DegenerationEarly Translational I$5,806,321
Dr. Gabriel H. TravisUniversity of California, Los AngelesDevelopment of a Stem Cell-based Transplantation Strategy for Treating Age-related Macular DegenerationEarly Translational I$5,487,136
Dr. David R. HintonUniversity of Southern CaliforniaTherapeutic potential of Retinal Pigment Epithelial cell lines derived from hES cells for retinal degeneration.SEED Grant$651,607
Dr. Mark S HumayunUniversity of Southern CaliforniaStem cell based treatment strategy for Age-related Macular Degeneration (AMD)Disease Team Research I$18,904,916

CIRM Videos about Vision Loss

Stem Cell Clinical Trial for Retinitis Pigmentosa: Rosie’s Story

Eyeing Stem Cell Therapies for Vision Loss

Masayo Takahashi – 2015 Winner of Ogawa-Yamanaka Stem Cell Prize

A Stem Cell-Based Clinical Trial for Retinitis Pigmentosa: Henry Klassen, UC Irvine

A Stem Cell-Based Therapy for Retinitis Pigmentosa: The Patient’s Perspective

Hossein Nazari, USC – CIRM Stem Cell #SciencePitch

Jacqueline Ward, UCSD – CIRM Stem Cell #SciencePitch

Mark Humayun, USC – CIRM Stem Cell #SciencePitch

Webinar: Focus on the Eye

Blindness: Advancing Stem Cell Therapies – 2011 CIRM Grantee Meeting

Cures through Collaboration: Funding a Team Approach to Disease Research

Video – Spotlight on Stem Cell Research: Devic’s Disease (NMO) – Introduction

Video – Spotlight on Stem Cell Research: Devic’s Disease (NMO) – Victoria Jackson

Video – Spotlight on Stem Cell Research: Devic’s Disease (NMO) – Michael Yeaman

Video – Spotlight on Stem Cell Research: Devic’s Disease (NMO) – Benjamin Greenberg

Video – Spotlight on Stem Cell Research: Devic’s Disease (NMO) – Candace Coffee

Progress and Promise in Macular Degeneration

Spotlight on Macular Degeneration: Welcoming Remarks

Spotlight on Macular Degeneration: Seminar by David Hinton, M.D.

Spotlight on Macular Degeneration: Seminar by Mark Humayun, M.D., Ph.D.

Spotlight on Macular Degeneration: Seminar by Sharon Hayes

Stem Cell Based Therapies for Blindness: David Hinton – CIRM Science Writer’s Seminar

News and Information


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