By Janet Fang
Posting in Design
In the second and third embryonic stem cell trials ever to be FDA-approved, California surgeons implanted lab-grown retinal cells into 2 patients with eye diseases.
For the first time ever, 2 patients have received human embryonic stem cell (hESC) therapy for diseases that cause blindness.
One 27-year-old woman has Stargardt’s Macular Dystrophy, a rare form of blindness that begins in childhood; the other, a 77-year-old woman, has dry age-related macular degeneration, a common cause of blindness in the elderly.
Both subjects were legally blind, and implanted into their eyes were lab-grown retinal pigment epithelial (RPE) cells derived from hESCs.
Last week, at the University of California, Los Angeles, a surgical team led by Steven Schwartz of UCLA’s Jules Stein Eye Institute transplanted the RPE cells into 2 patients. The study is sponsored by Santa Monica-based Advanced Cell Technology (ACT).
The Food and Drug Administration has only approved these 3 hESC trials to date. “Thirteen years after the discovery of human embryonic stem cells, the great promise of these cells is finally being put to the test," says ACT’s Robert Lanza.
These 2 clinical trials, each of which aim to enroll a dozen patients, will be assessing the safety and tolerability of ascending dosages of the cells over the course of a year.
The first 2 patients received ‘small’ doses of 50,000 cells each, transplanted into tissue directly under their retinas, which are lined with the light-sensing cells needed for vision.
Patients could receive as much as 200,000 retinal cells. (Eligibility here and here.)
In this therapy, hESCs are used to recreate the RPE cells that support photoreceptors. However, subjects won’t be getting their central vision back… this is a safety trial not designed to improve vision.
“I hope what happens is that we find this is safe and that we can optimize the dosing, and that allows us to move into eyes that are earlier in disease,” Lanza tells the Los Angeles Times. “That could have a real visual upside.”
According to the company, the patients are “recovering uneventfully.”
The degenerative Stargardt’s Macular Dystrophy affects roughly 1 in 10,000 US youngsters, while age-related macular degeneration affects millions of Americans.
Researchers see the start of a second set of tests as an important landmark for the stem cell field, as well as a major step for ACT, a tiny firm that has long been at the center of stem cell controversies. Twice the company laid off nearly its entire staff when its bank accounts hit zero. The start of the clinical trials is likely to stir hopes of a big payday among investors, Technology Review reports:
Advanced Cell's stock price has risen 170 percent during the last year, valuing the firm at $285 million based on Tuesday's stock price. Investors hope it could be worth several billion should the therapy succeed...
So far, however, embryonic stem cell research has been a money loser. Advanced Cell has run up losses of more than $180 million since it was founded in the mid-1990s. In recent years, it sold off programs for cloning cattle, and abandoned controversial efforts to clone human embryos in favor of a narrower approach.
"Things were crazy for a long while," Lanza says. "Times have really changed. The field is much tamer now."
Jul 17, 2011
In this therapy, hESCs are used to recreate the RPE cells that support photoreceptors. However, subjects won???t be getting their central vision back??? this is a safety trial not designed to improve vision. Glad to know that little fact that is overlooked in a lot of the reports.
I wonder how long before such treatment could be in the mainstream. Althought there are other promising therapies for the wet form of macular degeneration, there is presently nothing for the dry form, the latter being the most common.