Age-related macular degeneration (AMD) is the leading cause of vision loss in adults over 50 in the United States, affecting tens of millions of people. While effective treatments exist for the wet form of the disease, the more common dry form — particularly in its advanced stage, called geographic atrophy — has had very limited treatment options for most of its history.
That’s why stem cell therapy has generated so much attention in the retina world. The idea is straightforward: if the cells in the retina are dying, could we replace them with healthy new ones grown from stem cells?
It’s a question that Dr. Steven Schwartz, one of the founding doctors at Retina Vision Consultants, has spent much of his career working to answer. As principal investigator on the first FDA-approved clinical trial to transplant human embryonic stem cell-derived cells into patients with macular degeneration, Dr. Schwartz helped open an entirely new chapter in retinal medicine.
This article explains what stem cell therapy is, where the science stands today, and what it means for patients living with macular degeneration.
Key Takeaway: Stem cell therapy for macular degeneration is one of the most promising areas of retinal research, with early clinical trials showing that transplanted cells can survive safely in the human eye and may improve vision. These treatments are still investigational — not yet widely available — but the research is advancing. At Retina Vision Consultants, our doctors are actively involved in clinical trials exploring the future of retinal care.
Why Macular Degeneration Is So Difficult to Treat
To understand why stem cell therapy matters, it helps to understand what macular degeneration does to the eye.
Your retina — the thin layer of tissue at the back of your eye — contains millions of light-sensitive cells called photoreceptors. These cells are responsible for your central vision: reading, recognizing faces, driving, seeing fine detail. Beneath the photoreceptors sits a layer of support cells called the retinal pigment epithelium (RPE). The RPE nourishes and protects the photoreceptors, removes waste, and keeps the visual system functioning.
In macular degeneration, the RPE cells in the macula (the center of the retina) gradually deteriorate and die. Without their support layer, the photoreceptors above them die as well. The result is progressive, irreversible loss of central vision.
Wet AMD — the less common but more aggressive form — involves abnormal blood vessels growing beneath the retina and leaking fluid. This form is treated with anti-VEGF injections, which block the growth of these vessels and have been remarkably effective at preserving vision. Dr. Schwartz was among the early clinical investigators in the pivotal trials for anti-VEGF therapy, helping to establish the treatment that is now the standard of care at retina practices worldwide.
Dry AMD — the more common form, accounting for roughly 80–90% of cases — progresses more slowly but has historically had far fewer treatment options. In its advanced stage (geographic atrophy), large areas of RPE are lost, and vision loss becomes significant.
The core challenge is this: once RPE cells die, the body cannot replace them on its own. That’s where stem cell therapy comes in.
What Are Stem Cell Therapies for the Retina?
Stem cells are unique because they can develop into many different types of specialized cells. In the context of retinal disease, researchers have focused on using stem cells to grow healthy RPE cells in the laboratory, then transplanting those cells into the eye to replace the ones that have been lost.
The type of stem cell most studied for macular degeneration is the human embryonic stem cell (hESC). Scientists can direct these cells to differentiate — or mature — into RPE cells that closely resemble the ones naturally found in your eye. These lab-grown RPE cells are then carefully placed beneath the retina through a surgical procedure called a subretinal transplant.
The goal is twofold: first, that the transplanted cells survive and integrate into the existing retinal structure without being rejected by the immune system; and second, that they take over the job of the lost RPE — supporting and protecting the remaining photoreceptors before they, too, are lost.
The Breakthrough: First Human Stem Cell Transplant for Eye Disease
In 2012, a team led by Dr. Steven Schwartz at UCLA’s Jules Stein Eye Institute published a landmark paper in The Lancetreporting on the first human patients to receive transplants of hESC-derived RPE cells. It was a watershed moment: the first time human embryonic stem cell-derived cells had been successfully transplanted into human patients for any disease.
The initial report described two patients — one with Stargardt’s macular dystrophy (a form of inherited macular degeneration affecting younger people) and one with advanced dry AMD. Both received subretinal injections of RPE cells. The results were encouraging: the transplanted cells showed no signs of abnormal growth, tumor formation, or immune rejection, and neither patient lost vision during the observation period.
A larger follow-up study, also published in The Lancet in 2014, expanded to 18 patients across multiple centers. The findings reinforced the safety profile and revealed something the researchers had not expected: more than half of the patients showed measurable improvement in vision. For patients whose vision had been declining for years or decades, that improvement — however modest in some cases — was significant.
These trials were Phase 1/2, meaning their primary purpose was to establish whether the treatment was safe. The fact that patients also showed visual improvement suggested the transplanted cells were not only surviving but potentially functioning.
Dr. Schwartz’s research demonstrated that a stem cell-based treatment could be delivered safely to the human eye — a finding that has helped guide dozens of subsequent trials around the world.
Where Stem Cell Therapy Stands Today
Since those initial trials, the field of retinal stem cell therapy has continued to advance. Researchers around the world are now exploring multiple approaches, including transplanting RPE cells as a suspension (individual cells), as a thin sheet or patch, and using different stem cell sources such as induced pluripotent stem cells (iPSCs) — stem cells created from a patient’s own adult cells, which may reduce the risk of immune rejection.
Several important things are worth knowing about where things stand:
Stem cell therapy for macular degeneration is still investigational. No stem cell treatment for AMD is currently approved by the FDA for routine clinical use. All available treatments are being studied in clinical trials.
The safety data has been reassuring. Across multiple trials globally, hESC-derived RPE transplants have shown a favorable safety profile, with no evidence of tumor formation or uncontrolled cell growth — concerns that were initially among the biggest obstacles to stem cell therapy.
Newer approaches are building on the foundation. Some trials are testing RPE cell patches rather than cell suspensions, which may improve how well the transplanted cells integrate with the retina. Others are exploring gene therapy alongside cell therapy to address different aspects of the disease.
The goal is evolving. Early trials focused on advanced disease — patients who had already experienced significant vision loss. Researchers now believe that treating patients earlier in the disease process, before the photoreceptors are lost, could lead to even better outcomes. That shift underscores the importance of regular monitoring and early detection.
It’s also important to be direct about what stem cell therapy is not, at least not yet. It is not a cure for macular degeneration. It is not a replacement for proven treatments like anti-VEGF injections for wet AMD. And patients should be cautious about clinics that advertise unproven stem cell treatments outside of legitimate clinical trials — these unregulated procedures have harmed patients and are not the same as the carefully controlled research being done at academic medical centers.
What This Means for Patients at Retina Vision Consultants
You don’t need to be enrolled in a clinical trial to benefit from the expertise of a doctor who helped shape this field. Dr. Schwartz’s decades of research inform the way he practices medicine every day — from how he evaluates macular degeneration to how he counsels patients on their treatment options.
At Retina Vision Consultants, our doctors are actively involved in clinical research, including clinical trials exploring new therapies for wet and dry AMD, diabetic retinopathy, and other retinal diseases. For eligible patients, participation in a clinical trial can provide access to treatments not yet widely available, under close medical supervision.
If you’ve been diagnosed with macular degeneration — or if you have a family history and want to understand your risk — we’re here to help. Our approach begins with a thorough diagnostic evaluation using advanced retinal imaging, followed by an honest conversation about where you stand, what treatment options are available today, and what the future may hold.
To schedule an appointment, call us at (310) 269-8565 or request an appointment online.
