CIRM funded trial for AMD shows promising results

This upcoming July is healthy vision month, a time to remember the importance of making vision and eye health a priority. It’s also a time to think about the approximately 12 million people, 40 and over in the United States, that have a vision impairment. Vision can be something that many of us take for granted, but losing even a portion of it can have a profound impact on our everyday life. It can impact your ability to do everyday things, from basic hygiene routines and driving to hobbies such as reading, writing, or watching a film.

It is because of this that CIRM has made vision related problems a priority, providing over $69 million in funding for six clinical trials related to vision loss. There is reason to be hopeful as these trials have demonstrated promising results. One of these trials, conducted by Regenerative Patch Technologies LLC (RPT), announced today results from its CIRM funded clinical trial ($16.3 million) for advanced, dry age-related macular degeneration (AMD).

AMD is a progressive disease resulting in death of the retinal pigment epithelium (RPE), an area of the eye that plays a key role in maintaining vision. Damage to the RPE causes distortion to central vision and eventually leads to legal blindness. Thanks to CIRM funding, RPT and scientists at the University of Southern California (USC) and UC Santa Barbara (UCSB) are growing specialized RPE cells from human embryonic stem cells (hESCs), placing them on a single layer scaffold, and implanting the combination device in the back of the eye to try to reverse the blindness caused by AMD.

One of the trial participants is Anna Kuehl, a USC alumna and avid nature lover. She was diagnosed with AMD in her mid 30s and gradually began losing the central vision in her left eye. Although her peripheral vision remained intact, she could no longer make out people’s faces clearly, drive a car, or read the time on her watch. This also meant she would have much more difficulty going on the nature hikes she enjoys so much. After receiving treatment, she noticed improvements in her vision.

Anna was not alone in these improvements post treatment. The implant, known as CPCB-RPE1, was delivered to the worst eye of 15 patients with AMD. All treated eyes were legally-blind having a best corrected visual acuity (BCVA) of 20/200 or worse (20/20 indicates perfect vision).

Patients in the clinical trial were assessed for visual function and the results were as follows:

  • At an average of 34 months post-implantation (range 12-48 months), 27% (4/15) showed a greater than 5 letter improvement in BCVA and 33% (5/15) remained stable with a BCVA within 5 letters of baseline value. The improvements ranged from 7-15 letters or 1-3 lines on an eye chart.
  • In contrast, BCVA in the fellow, untreated eye declined by more than 5 letters (range 8-21 letters or 1-4 lines on an eye chart) in 80% (12/15) of subjects. There was no improvement in BCVA in the untreated eye of any subject. 
  • The implant was delivered safely and remained stably in place throughout the trial.
  • Refinements to the implantation procedure during the trial further improved its efficiency and safety profile.

In a news release from RPT, Mark Humayun, M.D., Ph.D., founder and co-owner of RPT, Director of the USC Ginsburg Institute for Biomedical Therapeutics and Co-Director of the USC Roski Eye Institute, Keck Medicine of USC, had this to say about the trial results.

“The improvements in best corrected visual acuity observed in some eyes receiving the implant are very promising, especially considering the very late stage of their disease. Improvements in visual acuity are exceedingly rare in geographic atrophy as demonstrated by the large decline in vision in many of the untreated eyes which also had disease. There are currently no approved therapies for this level of advanced dry age-related macular degeneration”. 

The full presentation can be found on RPT’s website linked here.

Watch the video below to learn more about Anna’s story.

Sometimes a cold stare is a good thing

A retina of a patient with macular degeneration. (Photo credit: Paul Parker/SPL)

Age-related macular degeneration (AMD) is the leading cause of vision loss and blindness in the elderly in the U.S. It’s estimated that some 11 million Americans could have some form of the disease, a number that is growing every year. So if you are going to develop a treatment for this condition, you need to make sure it can reach a lot of people easily. And that’s exactly what some CIRM-supported researchers are doing.

Let’s back up a little first. AMD is a degenerative condition where the macular, the small central portion of your retina, is slowly worn away. That’s crucial because the retina is the light-sensing nerve tissue at the back of your eye. At first you notice that your vision is getting blurry and it’s hard to read fine print or drive a car. As it progresses you develop dark, blurry areas in the center of your vision.

There are two kinds of AMD, a wet form and a dry form. The dry form is the most common, affecting 90% of patients. There is no cure and no effective treatment. But researchers at the University of Southern California (USC), the University of California Santa Barbara (UCSB) and a company called Regenerative Patch Technologies are developing a method that is looking promising.

They are using stem cells to grow retinal pigment epithelium (RPE) cells, the kind attacked by the disease, and putting them on a tiny synthetic scaffold which is then placed at the back of the eye. The hope is these RPE cells will help slow down the progression of the disease or even restore vision.

Early results from a CIRM-funded clinical trial are encouraging. Of the five patients enrolled in the Phase 1/2a trial, four maintained their vision in the treated eye, two showed improvement in the stability of their vision, and one patient had a 17-letter improvement in their vision on a reading chart. In addition, there were no serious side effects or unanticipated problems.

So now the team are taking this approach one step further. In a study published in Scientific Reports, they say they have developed a way to cryopreserve or freeze this cell and scaffold structure.

In a news release, Dr. Dennis Clegg of UCSB, says the frozen implants are comparable to the non-frozen ones and this technique will extend shelf life and enable on-demand distribution to distant clinical sites, increasing the number of patients able to benefit from such treatments.

“It’s a major advance in the development of cell therapies using a sheet of cells, or a monolayer of cells, because you can freeze them as the final product and ship them all over the world.”

Cool.

Why having a wrinkled brain is a good thing

Brain_01

We normally associate wrinkles with aging, such as wrinkled skin. But there’s one organ that is wrinkled right from the time we are born. It’s our brain. And new research shows those wrinkles are not a sign of age but are, in fact, a sign of just how large and complex our brains are.

The wrinkles, according to U.C. Santa Barbara (UCSB) postdoctoral scholar Eyal Karzbrun, are vital to our development because they create a greater surface area giving our neurons, or brain nerve cells, more space to create connections and deliver information.

In an article in UCSB’s Daily Nexus, Karzbrun says while our knowledge of the brain is increasing there are still many things we don’t understand:

“The brain is a complex organ whose organization is essential to its function. Yet it is ‘assembled by itself’. How this assembly takes place and what physics come into play is fundamental to our understanding of the brain.”

Eyal Karzbrun

Eyal Karzbrun: Photo courtesy UCSB

Karzbrun used stem cells to create 3D clusters of brain cells, to better understand how they organize themselves. He said brains are like computers in the way they rely on surface area to process information.

“In order to be computationally strong and quick, what your brain does is take a lot of surface area and put it in a small volume. The cerebral cortex, which occupies most of the volume in your brain, has a unique architecture in which neurons are layered on the outer surface of the brain, and the bulk of the brain is composed of axons, [or] biological wire which interconnect the neurons.”

Karzbrun says gaining a deeper understanding of how the brain is formed, and why it takes the shape it does, may help us develop new approaches to treating problems in the brain.