Human embryonic stem cells attempted to treat blindness

[Sheldon]

Nature News Blog: Firm launches two stem cell trials against blindness

Now, the second and third hESC trials have been launched. On July 12, in an operating room at the University of California, Los Angeles, the first subject in each of the trials -- one for a rare form of blindness that usually begins in childhood, the other for a common cause of blindness in the elderly -- was treated with retinal pigment epithelial (RPE) cells derived from hESCs. Details are available in this press release from the sponsoring company, Advanced Cell Technology, based in Santa Monica.

...

The trials, each of which aims to enroll 12 patients, will assess over the course of one year the safety and tolerability of ascending dosages of the cells. The first two patients received what are considered small doses -- 50,000 cells each -- transplanted into the tissue directly under their retinas.

"Early indications are that the patients tolerated the surgical procedures well," Schwartz said in the press release.

.

 

[waltky]

Synthetic retina grown from embryonic stem cells...

Procedure Could Reverse Common Form of Blindness
July 22, 2013 > Scientists have taken a major step toward potentially reversing a common form of blindness.

Researchers at the University College London (UCL) successfully transplanted light-sensitive photoreceptor cells from a synthetic retina that was grown from embryonic stem cells into night-blind mice. Photoreceptor cells are light sensitive nerve cells at the back of the eye. Many forms of blindness -- including age-related macular degeneration, retinitis pigmentosa and diabetes-related blindness -- are caused by the loss of these cells. The transplanted cells appeared to develop normally into the mice’s retina and formed nerve connections needed to communicate visual information to the brain, the researchers said.

In the future, the process could provide an unlimited supply of healthy photoreceptor cells for transplantation into human retinas. “Over recent years scientists have become pretty good at working with stem cells and coaxing them to develop into different types of adult cells and tissues,” said Professor Robin Ali of UCL. “But until recently, the complex structure of the retina has proved difficult to reproduce in the lab. This is probably because the type of cell culture we were using was not able to recreate the developmental process that would happen in a normal embryo.”

Scientists say they have taken a major step in reversing common forms of blindness.

The researchers grew the cells using a 3D culture method developed in Japan. Throughout the process, the cells were compared to cells developed normally to ensure they were biologically equivalent. Scientists then transplanted about 200,000 of the cells and injected them into the retina of night-blind mice.

Three weeks after the procedure, the injected cells began to look like normal, mature photoreceptor cells. Six weeks after the procedure, the cells were still there, and researchers noticed nerve connections with the existing retinal circuitry. “The new 3D technique more closely mimics normal development, which means we are able to pick out and purify the cells at precisely the right stage to ensure successful transplantation,” said Ali. “The next step will be to refine this technique using human cells to enable us to start clinical trials.”

Procedure Could Reverse Common Form of Blindness

 

[waltky]

Michigan Man Sees Thanks to 'Bionic Eye'...

Michigan man among 1st in US to get 'bionic eye'
23 Apr.`14 — A degenerative eye disease slowly robbed Roger Pontz of his vision.

Diagnosed with retinitis pigmentosa as a teenager, Pontz has been almost completely blind for years. Now, thanks to a high-tech procedure that involved the surgical implantation of a "bionic eye," he has regained enough of his eyesight to catch small glimpses of his wife, grandson and cat. "It's awesome. It's exciting — seeing something new every day," Pontz said during a recent appointment at the University of Michigan Kellogg Eye Center. The 55-year-old former competitive weightlifter and factory worker is one of four people in the U.S. to receive an artificial retina since the Food and Drug Administration signed off on its use last year. The facility in Ann Arbor has been the site of all four such surgeries since FDA approval. A fifth is scheduled for next month.

Retinitis pigmentosa is an inherited disease that causes slow but progressive vision loss due to a gradual loss of the light-sensitive retinal cells called rods and cones. Patients experience loss of side vision and night vision, then central vision, which can result in near blindness. Not all of the 100,000 or so people in the U.S. with retinitis pigmentosa can benefit from the bionic eye. An estimated 10,000 have vision low enough, said Dr. Brian Mech, an executive with Second Sight Medical Products Inc., the Sylmar, Calif.-based company that makes the device. Of those, about 7,500 are eligible for the surgery. The artificial implant in Pontz's left eye is part of a system developed by Second Sight that includes a small video camera and transmitter housed in a pair of glasses.

Images from the camera are converted into a series of electrical pulses that are transmitted wirelessly to an array of electrodes on the surface of the retina. The pulses stimulate the retina's remaining healthy cells, causing them to relay the signal to the optic nerve. The visual information then moves to the brain, where it is translated into patterns of light that can be recognized and interpreted, allowing the patient to regain some visual function. When wearing the glasses, which Pontz refers to as his "eyes," he can identify and grab his cat and figure out that a flash of light is his grandson hightailing it to the kitchen. The visual improvement is sometimes startling for Pontz and his wife, Terri, who is just as amazed at her husband's progress as he is. "I said something I never thought I'd say: 'Stop staring at me while I'm eating,'" Terri Pontz said.

She drives her husband the nearly 200 miles from tiny Reed City, Mich., to Ann Arbor for check-ups and visits with occupational therapist Ashley Howson, who helps Roger Pontz reawaken his visual memory and learn techniques needed to make the most of his new vision. At the recent visit, Howson handed Pontz white and black plates, instructed him to move them back and forth in front of light and dark backgrounds and asked that he determine their color. Back home, Terri Pontz helps her husband practice the techniques he learns in Ann Arbor. For them, the long hours on the road and the homework assignments are a blessing. "What's it worth to see again? It's worth everything," Terri Pontz said.

MORE

 

[waltky]

FDA Panel Considers Gene Therapy for Blindness...

Seeing Hope: FDA Panel Considers Gene Therapy for Blindness
October 09, 2017 - A girl saw her mother's face for the first time. A boy tore through the aisles of Target, marveling at toys he never knew existed. A teen walked onto a stage and watched the stunned expressions of celebrity judges as he wowed America's Got Talent. Caroline, Cole, Christian. All had mere glimmers of vision and were destined to lose even that because of an inherited eye disease with no treatment or cure. Until now.

On Thursday, U.S. Food and Drug Administration advisers will consider whether to recommend approval of a gene therapy that improved vision for these three youths and some others with hereditary blindness. It would be the first gene therapy in the U.S. for an inherited disease, and the first in which a corrective gene is given directly to a patient. Only one gene therapy is sold in the U.S. now, a cancer treatment approved in August that engineers patients' blood cells in the lab.

A hearing like no other

Children, parents, doctors and scientists will tell the FDA panel what it's like to lack and then gain one of our most primal senses. Cole Carper, an 11-year-old boy who got the therapy when he was 8, describes how sight changed what he knew of the world. When he returned to his home in Little Rock, Arkansas, after treatment, "I looked up and said, 'What are those light things?' And my mom said, 'Those are stars."'

Beth Guardino, left, and her son, Christian, talk about the 17-year-old's life before and after gene therapy treatment for his hereditary blindness during an interview at their home in Patchogue, N.Y.​

His sister, 13-year-old Caroline Carper, treated when she was 10, said that afterward, "I saw snow falling and rain falling. I was completely surprised. I thought of water on the ground or snow on the ground. I never thought of it falling," because the sky was something she couldn't see, along with other things like her mother's smile.

Dr. Albert Maguire checks the eyes of Misa Kaabali, 8, at the Children’s Hospital of Philadelphia, Oct. 4, 2017. Misa was 4 years old when he received his gene therapy treatment.​

The treatment, Luxturna, is made by Philadelphia-based Spark Therapeutics. It does not give 20-20 vision or work for everyone, but a company-funded study found it improved vision for nearly all of those given it and seemed safe. The company's Nasdaq ticker symbol is ONCE, for how often it hopes the therapy is needed. "It's exciting" and in some cases might be a cure, although how long the benefits last isn't known, said Dr. Paul Yang, an eye specialist at Oregon Health & Science University who is testing gene therapies for other companies. "There's nothing else for these kids."

How it works

 

[waltky]

New Gene Therapy for Rare Form of Blindness Wins US Approval...

Gene Therapy for Rare Form of Blindness Wins US Approval
December 19, 2017 | WASHINGTON — U.S. health officials on Tuesday approved the nation's first gene therapy for an inherited, rare form of blindness, marking another major advance for the emerging field of genetic medicine.

The approval for pharmaceutical company Spark Therapeutics offers a life-changing intervention for a small group of patients with a vision-destroying genetic mutation and hope for many more people with other inherited diseases. The drugmaker said it would not disclose the price until next month, delaying debate about the affordability of a treatment that analysts predict will be priced around $1 million. The injection, called Luxturna, is the first gene therapy approved by the Food and Drug Administration in which a corrective gene is given directly to patients. The gene mutation interferes with the production of an enzyme needed for normal vision.

Dr. Albert Maguire checks the eyes of Misa Kaabali, 8, at Children's Hospital of Philadelphia, Oct. 4, 2017. Misa was 4 when he received his gene therapy treatment. On Dec. 19, 2017, the Food and Drug Administration approved therapy that improves the vision of patients with a rare form of inherited blindness, another major advance for the burgeoning field of genetic medicine.​

Patients who got the treatment have described seeing snow, stars or the moon for the first time. "One of the best things I've ever seen since surgery are the stars. I never knew that they were little dots that twinkled," said Mistie Lovelace of Kentucky, one of several patients who urged the FDA to approve the therapy at a public hearing in October. Patients with the condition generally start losing their sight before 18, almost always progressing to total blindness. The defective gene that causes the disease can be passed down for generations undetected before suddenly appearing when a child inherits a copy from both parents. Only a few thousand people in the U.S. are thought to have the condition.

One injection per eye

Luxturna is delivered via an injection for each eye; they replace the defective gene that prevents the retina — tissue at the back of the eye — from converting light into electronic signals sent to the brain. The FDA has approved three gene therapies since August, as decades of research into the genetic building blocks of life begin translating into marketable treatments. The previous two were custom-made treatments for forms of blood cancer. Novartis' Kymriah is priced at $475,000 for a one-time infusion of genetically enhanced cells. Gilead Sciences' similar treatment, Yescarta, costs $373,000 per treatment. Philadelphia-based Spark Therapeutics said it would announce its price in early January, but suggested its own analysis put the value of the therapy at about $1 million. Key to the company's reasoning is the assumption that Luxturna will be given once, with lasting benefits. To date, the company has tracked patients enrolled in a key study for as long as four years and hasn't seen their vision deteriorate. "All the data we have today suggests it's long-lasting, if not lifelong," said Spark CEO Jeffrey Marrazzo.

Given Luxturna's FDA approval and strong study results, many experts expect U.S. insurers, including both the federal government and private plans, to cover the treatment. The spate of new genetic therapies marks a boom for a field once plagued by safety concerns. Gene therapy research suffered a setback in 1999 with the death of a patient treated for a rare metabolic disorder at the University of Pennsylvania. In another case, patients treated for an immune disorder later developed leukemia. Dr. David Valle said initial excitement about the wide-ranging possibilities for genetic medicine has given way to a more deliberative approach focused on individual diseases. He applauded researchers at the University of Pennsylvania for decades of work that led to the treatment. "The hype for gene therapy has been without many successes and actually a few failures, so chalk this one up in the win column," said Valle, a geneticist and pediatrician at Johns Hopkins University, who was not involved in Luxturna's development.

Development took years