Researchers Are Testing a New Stem Cell Therapy in the Hopes of Saving Millions from Blindness
Of all the infirmities of old age, failing sight is among the cruelest. It can mean the end not only of independence, but of a whole spectrum of joys—from gazing at a sunset or a grandchild's face to reading a novel or watching TV.
The Phase 1 trial will likely run through 2022, followed by a larger Phase 2 trial that could last another two or three years.
The leading cause of vision loss in people over 55 is age-related macular degeneration, or AMD, which afflicts an estimated 11 million Americans. As photoreceptors in the macula (the central part of the retina) die off, patients experience increasingly severe blurring, dimming, distortions, and blank spots in one or both eyes.
The disorder comes in two varieties, "wet" and "dry," both driven by a complex interaction of genetic, environmental, and lifestyle factors. It begins when deposits of cellular debris accumulate beneath the retinal pigment epithelium (RPE)—a layer of cells that nourish and remove waste products from the photoreceptors above them. In wet AMD, this process triggers the growth of abnormal, leaky blood vessels that damage the photoreceptors. In dry AMD, which accounts for 80 to 90 percent of cases, RPE cells atrophy, causing photoreceptors to wither away. Wet AMD can be controlled in about a quarter of patients, usually by injections of medication into the eye. For dry AMD, no effective remedy exists.
Stem Cells: Promise and Perils
Over the past decade, stem cell therapy has been widely touted as a potential treatment for AMD. The idea is to augment a patient's ailing RPE cells with healthy ones grown in the lab. A few small clinical trials have shown promising results. In a study published in 2018, for example, a University of Southern California team cultivated RPE tissue from embryonic stem cells on a plastic matrix and transplanted it into the retinas of four patients with advanced dry AMD. Because the trial was designed to test safety rather than efficacy, lead researcher Amir Kashani told a reporter, "we didn't expect that replacing RPE cells would return a significant amount of vision." Yet acuity improved substantially in one recipient, and the others regained their lost ability to focus on an object.
Therapies based on embryonic stem cells, however, have two serious drawbacks: Using fetal cell lines raises ethical issues, and such treatments require the patient to take immunosuppressant drugs (which can cause health problems of their own) to prevent rejection. That's why some experts favor a different approach—one based on induced pluripotent stem cells (iPSCs). Such cells, first produced in 2006, are made by returning adult cells to an undifferentiated state, and then using chemicals to reprogram them as desired. Treatments grown from a patient's own tissues could sidestep both hurdles associated with embryonic cells.
At least hypothetically. Today, the only stem cell therapies approved by the U.S. Food and Drug Administration (FDA) are umbilical cord-derived products for various blood and immune disorders. Although scientists are probing the use of embryonic stem cells or iPSCs for conditions ranging from diabetes to Parkinson's disease, such applications remain experimental—or fraudulent, as a growing number of patients treated at unlicensed "stem cell clinics" have painfully learned. (Some have gone blind after receiving bogus AMD therapies at those facilities.)
Last December, researchers at the National Eye Institute in Bethesda, Maryland, began enrolling patients with dry AMD in the country's first clinical trial using tissue grown from the patients' own stem cells. Led by biologist Kapil Bharti, the team intends to implant custom-made RPE cells in 12 recipients. If the effort pans out, it could someday save the sight of countless oldsters.
That, however, is what's technically referred to as a very big "if."
The First Steps
Bharti's trial is not the first in the world to use patient-derived iPSCs to treat age-related macular degeneration. In 2013, Japanese researchers implanted such cells into the eyes of a 77-year-old woman with wet AMD; after a year, her vision had stabilized, and she no longer needed injections to keep abnormal blood vessels from forming. A second patient was scheduled for surgery—but the procedure was canceled after the lab-grown RPE cells showed signs of worrisome mutations. That incident illustrates one potential problem with using stem cells: Under some circumstances, the cells or the tissue they form could turn cancerous.
"The knowledge and expertise we're gaining can be applied to many other iPSC-based therapies."
Bharti and his colleagues have gone to great lengths to avoid such outcomes. "Our process is significantly different," he told me in a phone interview. His team begins with patients' blood stem cells, which appear to be more genomically stable than the skin cells that the Japanese group used. After converting the blood cells to RPE stem cells, his team cultures them in a single layer on a biodegradable scaffold, which helps them grow in an orderly manner. "We think this material gives us a big advantage," Bharti says. The team uses a machine-learning algorithm to identify optimal cell structure and ensure quality control.
It takes about six months for a patch of iPSCs to become viable RPE cells. When they're ready, a surgeon uses a specially-designed tool to insert the tiny structure into the retina. Within days, the scaffold melts away, enabling the transplanted RPE cells to integrate fully into their new environment. Bharti's team initially tested their method on rats and pigs with eye damage mimicking AMD. The study, published in January 2019 in Science Translational Medicine, found that at ten weeks, the implanted RPE cells continued to function normally and protected neighboring photoreceptors from further deterioration. No trace of mutagenesis appeared.
Encouraged by these results, Bharti began recruiting human subjects. The Phase 1 trial will likely run through 2022, followed by a larger Phase 2 trial that could last another two or three years. FDA approval would require an even larger Phase 3 trial, with a decision expected sometime between 2025 and 2028—that is, if nothing untoward happens before then. One unknown (among many) is whether implanted cells can thrive indefinitely under the biochemically hostile conditions of an eye with AMD.
"Most people don't have a sense of just how long it takes to get something like this to work, and how many failures—even disasters—there are along the way," says Marco Zarbin, professor and chair of Ophthalmology and visual science at Rutgers New Jersey Medical School and co-editor of the book Cell-Based Therapy for Degenerative Retinal Diseases. "The first kidney transplant was done in 1933. But the first successful kidney transplant was in 1954. That gives you a sense of the time frame. We're really taking the very first steps in this direction."
Looking Ahead
Even if Bharti's method proves safe and effective, there's the question of its practicality. "My sense is that using induced pluripotent stem cells to treat the patient from whom they're derived is a very expensive undertaking," Zarbin observes. "So you'd have to have a very dramatic clinical benefit to justify that cost."
Bharti concedes that the price of iPSC therapy is likely to be high, given that each "dose" is formulated for a single individual, requires months to manufacture, and must be administered via microsurgery. Still, he expects economies of scale and production to emerge with time. "We're working on automating several steps of the process," he explains. "When that kicks in, a technician will be able to make products for 10 or 20 people at once, so the cost will drop proportionately."
Meanwhile, other researchers are pressing ahead with therapies for AMD using embryonic stem cells, which could be mass-produced to treat any patient who needs them. But should that approach eventually win FDA approval, Bharti believes there will still be room for a technique that requires neither fetal cell lines nor immunosuppression.
And not only for eye ailments. "The knowledge and expertise we're gaining can be applied to many other iPSC-based therapies," says the scientist, who is currently consulting with several companies that are developing such treatments. "I'm hopeful that we can leverage these approaches for a wide range of applications, whether it's for vision or across the body."
NEI launches iPS cell therapy trial for dry AMD
The Friday Five covers five stories in research that you may have missed this week. There are plenty of controversies and troubling ethical issues in science – and we get into many of them in our online magazine – but this news roundup focuses on new scientific theories and progress to give you a therapeutic dose of inspiration headed into the weekend.
This episode includes an interview with Dr. Helen Keyes, Head of the School of Psychology and Sports Science at Anglia Ruskin University.
Listen on Apple | Listen on Spotify | Listen on Stitcher | Listen on Amazon | Listen on Google
- Attending sports events is linked to greater life satisfaction
- Identifying specific brain tumors in under 90 seconds with AI
- LSD - minus hallucinations - raises hopes for mental health
- New research on the benefits of cold showers
- Inspire awe in your kids and reap the benefits
The rise of remote work is a win-win for people with disabilities and employers
Disability advocates see remote work as a silver lining of the pandemic, a win-win for adults with disabilities and the business world alike.
Any corporate leader would jump at the opportunity to increase their talent pool of potential employees by 15 percent, with all these new hires belonging to an underrepresented minority. That’s especially true given tight labor markets and CEO desires to increase headcount. Yet, too few leaders realize that people with disabilities are the largest minority group in this country, numbering 50 million.
Some executives may dread the extra investments in accommodating people’s disabilities. Yet, providing full-time remote work could suffice, according to a new study by the Economic Innovation Group think tank. The authors found that the employment rate for people with disabilities did not simply reach the pre-pandemic level by mid-2022, but far surpassed it, to the highest rate in over a decade. “Remote work and a strong labor market are helping [individuals with disabilities] find work,” said Adam Ozimek, who led the research and is chief economist at the Economic Innovation Group.
Disability advocates see this development as a silver lining of the pandemic, a win-win for adults with disabilities and the business world alike. For decades before the pandemic, employers had refused requests from workers with disabilities to work remotely, according to Thomas Foley, executive director of the National Disability Institute. During the pandemic, "we all realized that...many of us could work remotely,” Foley says. “[T]hat was disproportionately positive for people with disabilities."
Charles-Edouard Catherine, director of corporate and government relations for the National Organization on Disability, said that remote-work options had been advocated for many years to accommodate disabilities. “It’s a little frustrating that for decades corporate America was saying it’s too complicated, we’ll lose productivity, and now suddenly it’s like, sure, let’s do it.”
The pandemic opened doors for people with disabilities
Early in the pandemic, employment rates dropped for everyone, including people with disabilities, according to Ozimek’s research. However, these rates recovered quickly. In the second quarter of 2022, people with disabilities aged 25 to 54, the prime working age, are 3.5 percent more likely to be employed, compared to before the pandemic.
What about people without disabilites? They are still 1.1 percent less likely to be employed.
These numbers suggest that remote work has enabled a substantial number of people with disabilities to find and retain employment.
“We have a last-in, first-out labor market, and [people with disabilities] are often among the last in and the first out,” Ozimek says. However, this dynamic has changed, with adults with disabilities seeing employment rates recover much faster. Now, the question is whether the new trend will endure, Ozimek adds. “And my conclusion is that not only is it a permanent thing, but it’s going to improve.”
Gene Boes, president and chief executive of the Northwest Center, a Seattle organization that helps people with disabilities become more independent, confirms this finding. “The new world we live in has opened the door a little bit more…because there’s just more demand for labor.”
Long COVID disabilities put a premium on remote work
Remote work can help mitigate the impact of long COVID. The U.S. Centers for Disease Control and Prevention reports that about 19 percent of those who had COVID developed long COVID. Recent Census Bureau data indicates that 16 million working age Americans suffer from it, with economic costs estimated at $3.7 trillion.
Certainly, many of these so-called long-haulers experience relatively mild symptoms - such as loss of smell - which, while troublesome, are not disabling. But other symptoms are serious enough to be disabilities.
According to a recent study from the Federal Reserve Bank of Minneapolis, about a quarter of those with long COVID changed their employment status or working hours. That means long COVID was serious enough to interfere with work for 4 million people. For many, the issue was serious enough to qualify them as disabled.
Indeed, the Federal Reserve Bank of New York found in a just-released study that the number of individuals with disabilities in the U.S. grew by 1.7 million. That growth stemmed mainly from long COVID conditions such as fatigue and brain fog, meaning difficulties with concentration or memory, with 1.3 million people reporting an increase in brain fog since mid-2020.
Many had to drop out of the labor force due to long COVID. Yet, about 900,000 people who are newly disabled have managed to continue working. Without remote work, they might have lost these jobs.
For example, a software engineer at one of my client companies has struggled with brain fog related to long COVID. With remote work, this employee can work during the hours when she feels most mentally alert and focused, even if that means short bursts of productivity throughout the day. With flexible scheduling, she can take rests, meditate, or engage in activities that help her regain focus and energy. Without the need to commute to the office, she can save energy and time and reduce stress, which is crucial when dealing with brain fog.
In fact, the author of the Federal Reserve Bank of New York study notes that long COVID can be considered a disability under the Americans with Disability Act, depending on the specifics of the condition. That means the law can require private employers with fifteen or more staff, as well as government agencies, to make reasonable accommodations for those with long COVID. Richard Deitz, the author of this study, writes in the paper that “telework and flexible scheduling are two accommodations that can be particularly beneficial for workers dealing with fatigue and brain fog.”
The current drive to return to the office, led by many C-suite executives, may need to be reconsidered in light of legal and HR considerations. Arlene S. Kanter, director of the disability law and policy program at the Syracuse University College of Law, said that the question should depend on whether people with disabilities can perform their work well at home, as they did during Covid outbreaks. “[T]hen people with disabilities, as a matter of accommodation, shouldn’t be denied that right,” Kanter said.
Diversity benefits
But companies shouldn’t need to worry about legal regulations. It simply makes dollars and sense to expand their talent pool by 15% of an underrepresented minority. After all, extensive research shows that improving diversity boosts both decision-making and financial performance.
Companies that are offering more flexible work options have already gained significant benefits in terms of diverse hires. In its efforts to adapt to the post-pandemic environment, Meta, the owner of Facebook and Instagram, decided to offer permanent fully remote work options to its entire workforce. And according to Meta chief diversity officer Maxine Williams, the candidates who accepted job offers for remote positions were “substantially more likely” to come from diverse communities: people with disabilities, Black, Hispanic, Alaskan Native, Native American, veterans, and women. The numbers bear out these claims: people with disabilities increased from 4.7 to 6.2 percent of Meta’s employees.
Having consulted for 21 companies to help them transition to hybrid work arrangements, I can confirm that Meta’s numbers aren’t a fluke. The more my clients proved willing to offer remote work, the more staff with disabilities they recruited - and retained. That includes employees with mobility challenges. But it also includes employees with less visible disabilities, such as people with long COVID and immunocompromised people who feel reluctant to put themselves at risk of getting COVID by coming into the office.
Unfortunately, many leaders fail to see the benefits of remote work for underrepresented groups, such as those with disabilities. Some even say the opposite is true, with JP Morgan CEO Jamie Dimon claiming that returning to the office will aid diversity.
What explains this poor executive decision making? Part of the answer comes from a mental blindspot called the in-group bias. Our minds tend to favor and pay attention to the concerns of those in the group of people who seem to look and think like us. Dimon and other executives without disabilities don’t perceive people with disabilities to be part of their in-group. They thus are blind to the concerns of those with disabilities, which leads to misperceptions such as Dimon’s that returning to the office will aid diversity.
In-group bias is one of many dangerous judgment errors known as cognitive biases. They impact decision making in all life areas, ranging from the future of work to relationships.
Another relevant cognitive bias is the empathy gap. This term refers to our difficulty empathizing with those outside of our in-group. The lack of empathy combines with the blindness from the in-group bias, causing executives to ignore the feelings of employees with disabilities and prospective hires.
Omission bias also plays a role. This dangerous judgment error causes us to perceive failure to act as less problematic than acting. Consequently, executives perceive a failure to support the needs of those with disabilities as a minor matter.
Conclusion
The failure to empower people with disabilities through remote work options will prove costly to the bottom lines of companies. Not only are limiting their talent pool by 15 percent, they’re harming their ability to recruit and retain diverse candidates. And as their lawyers and HR departments will tell them, by violating the ADA, they are putting themselves in legal jeopardy.
By contrast, companies like Meta - and my clients - that offer remote work opportunities are seizing a competitive advantage by recruiting these underrepresented candidates. They’re lowering costs of labor while increasing diversity. The future belongs to the savvy companies that offer the flexibility that people with disabilities need.