Dr. Mark Humayun

Sometimes a cold stare is a good thing

/ Kevin McCormack / 6 Comments
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.

CIRM Board Approves $19.7 Million in Awards for Translational Research Program

/ Yimy Villa / 2 Comments

In addition to approving funding for breast cancer related brain metastases last week, the CIRM Board also approved an additional $19.7 million geared towards our translational research program. The goal of this program is to help promising projects complete the testing needed to begin talking to the US Food and Drug Administration (FDA) about holding a clinical trial.

Before getting into the details of each project, here is a table with a brief synopsis of the awards:

TRAN1 – 11532

Illustration of a healthy eye vs eye with AMD

$3.73 million was awarded to Dr. Mark Humayun at USC to develop a novel therapeutic product capable of slowing the progression of age-related macular degeneration (AMD).

AMD is an eye disease that causes severe vision impairment, resulting in the inability to read, drive, recognize faces, and blindness if left untreated.  It is the leading cause of vision loss in the U.S. and currently affects over 2 million Americans.  By the year 2050, it is projected that the number of affected individuals will more than double to over 5 million.  A layer of cells in the back of the eye called the retinal pigment epithelium (RPE) provide support to photoreceptors (PRs), specialized cells that play an important role in our ability to process images.  The dysfunction and/or loss of RPE cells plays a critical role in the loss of PRs and hence the vision problems observed in AMD.  One form of AMD is known as dry AMD (dAMD) and accounts for about 90% of all AMD cases.

The approach that Dr. Humayun is developing will use a biologic product produced by human embryonic stem cells (hESCs). This material will be injected into the eye of patients with early development of dAMD, supporting the survival of photoreceptors in the affected retina.

TRAN1 – 11579

Illustration depicting the role neuronal relays play in muscle sensation

$6.23 million was awarded to Dr. Mark Tuszynski at UCSD to develop a neural stem cell therapy for spinal cord injury (SCI).

According to data from the National Spinal Cord Injury Statistical Center, as of 2018, SCI affects an estimated 288,000 people in the United States alone, with about 17,700 new cases each year. There are currently no effective therapies for SCI. Many people suffer SCI in early adulthood, leading to life-long disability and suffering, extensive treatment needs and extremely high lifetime costs of health care.

The approach that Dr. Tuszynski is developing will use hESCs to create neural stem cells (NSCs).  These newly created NSCs would then be grafted at the site of injury of those with SCI.  In preclinical studies, the NSCs have been shown to support the formation of neuronal relays at the site of SCI.  The neuronal relays allow the sensory neurons in the brain to communicate with the motor neurons in the spinal cord to re-establish muscle control and movement.

TRAN1 – 11548

Graphic depicting the challenges of traumatic brain injury (TBI)

$4.83 million was awarded to Dr. Brian Cummings at UC Irvine to develop a neural stem cell therapy for traumatic brain injury (TBI).

TBI is caused by a bump, blow, or jolt to the head that disrupts the normal function of the brain, resulting in emotional, mental, movement, and memory problems. There are 1.7 million people in the United States experiencing a TBI that leads to hospitalization each year. Since there are no effective treatments, TBI is one of the most critical unmet medical needs based on the total number of those affected and on a cost basis.

The approach that Dr. Cummings is developing will also use hESCs to create NSCs.  These newly created NSCs would be integrated with injured tissue in patients and have the ability to turn into the three main cell types in the brain; neurons, astrocytes, and oligodendrocytes.  This would allow for TBI patients to potentially see improvements in issues related to memory, movement, and anxiety, increasing independence and lessening patient care needs.

TRAN1 – 11628

Illustration depicting the brain damage that occurs under hypoxic-ischemic conditions

$4.96 million was awarded to Dr. Evan Snyder at Sanford Burnham Prebys to develop a neural stem cell therapy for perinatal hypoxic-ischemic brain injury (HII).

HII occurs when there is a lack of oxygen flow to the brain.  A newborn infant’s body can compensate for brief periods of depleted oxygen, but if this lasts too long, brain tissue is destroyed, which can cause many issues such as developmental delay and motor impairment.  Current treatment for this condition is whole-body hypothermia (HT), which consists of significantly reducing body temperature to interrupt brain injury.  However, this is not very effective in severe cases of HII. 

The approach that Dr. Snyder is developing will use an established neural stem cell (NSC) line.   These NSCs would be injected and potentially used alongside HT treatment to increase protection from brain injury.

Encouraging news about CIRM-funded clinical trial targeting vision loss

/ Kevin McCormack / 3 Comments

dry AMD

An eye affected by dry age-related macular degeneration

Dry age-related macular degeneration (AMD) is the leading cause of vision loss in the U.S. By 2020 it’s estimated that as many as three million Americans will be affected by the disease. Right now, there is no effective therapy. But that could change. A new CIRM-funded clinical trial is showing promise in helping people battling the disease not just in stabilizing their vision loss, but even reversing it.

In AMD, cells in the retina, the light-sensitive tissue at the back of the eye, are slowly destroyed affecting a person’s central vision. It can make it difficult to do everyday activities such as reading or watching TV and make it impossible for a person to drive.

Researchers at the University of Southern California (USC) Roski Eye Institute at the Keck School of Medicine, and Regenerative Patch Technologies, have developed a therapy using embryonic stem cells that they turned into retinal pigment epithelium (RPE) cells – the kind of cell destroyed by AMD. These cells were then placed on a synthetic scaffold which was surgically implanted in the back of the eye.

Imaging studies showed that the RPE cells appeared to integrate well into the eye and remained in place during follow-up tests 120 to 365 days after implantation.

Encouraging results

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.

There were other indications the implants were proving beneficial.  People with normal vision have the ability to focus their gaze on a single location. People with advanced AMD lose that ability. In this trial, two of the patients recovered stable fixation. These improvements were maintained in follow-up tests.

Abla-8

Abla Creasey, Ph.D., CIRM’S Vice President of Therapeutics and Strategic Infrastructure says even these small benefits are important:

“Having a therapy with a favorable safety profile, that could slow down the progression, or even reverse the vision loss would benefit millions of Americans. That’s why these results, while still in an early stage are encouraging, because the people treated in the trial are ones most severely affected by the disease who have the least potential for visual recovery.”

This study reflects CIRM’s long-term commitment to supporting the most promising stem cell research. The Stem Cell Agency began supporting USC’s Dr. Mark Humayun, the lead inventor of the implant, in 2010 and has been a partner with him and his team since then.

Dr.MarkHumayun2 copy

In a news release Dr. Humayun said they plan to recruit another 15 patients to see if these results hold up:

“Our study shows that this unique stem cell–based retinal implant thus far is well-tolerated, and preliminary results suggest it may help people with advanced dry age-related macular degeneration.”

While the results, published in the journal Science Translational Medicine, are encouraging the researchers caution that this was a very early stage clinical trial, with a small number of patients. They say the next step is to continue to follow the four patients treated in this trial to see if there are any further changes to their vision, and to conduct a larger trial.