CIRM-funded treatment for Cystinosis receives orphan drug designation

Dr. Stephanie Cherqui, UC San Diego

Orphan drug designation is a special status given by the Food and Drug Administration (FDA) for potential treatments of rare diseases that affect fewer than 200,000 in the U.S. This type of status can significantly help advance treatments for rare diseases by providing financial incentives in the form of tax credits towards the cost of clinical trials and prescription drug user fee waivers.

Fortunately for us, a stem cell-gene therapy approach used in a CIRM-funded clinical trial for Cystinosis has just received orphan drug designation. The trial is being conducted by Dr. Stephanie Cherqui at UC San Diego, which is an academic collaborator for AVROBIO, Inc.

Cystinosis is a rare disease that primarily affects children and young adults, and leads to premature death, usually in early adulthood.  Patients inherit defective copies of a gene called CTNS, which results in abnormal accumulation of an amino acid called cystine in all cells of the body.  This buildup of cystine can lead to multi-organ failure, with some of earliest and most pronounced effects on the kidneys, eyes, thyroid, muscle, and pancreas.  Many patients suffer end-stage kidney failure and severe vision defects in childhood, and as they get older, they are at increased risk for heart disease, diabetes, bone defects, and neuromuscular defects. 

Dr. Cherqui’s clinical trial uses a gene therapy approach to modify a patient’s own blood stem cells with a functional version of the defective CTNS gene. The goal of this treatment is to reintroduce the corrected stem cells into the patient to give rise to blood cells that will reduce cystine buildup in affected tissues.  

In an earlier blog, we shared a story by UCSD news that featured Jordan Janz, the first patient to participate in this trial, as well as the challenges promising approaches like this one face in terms of getting financial support. Our hope is that in addition to the funding we have provided, this special designation gives additional support to what appears to be a very promising treatment for a very rare disease.

You can read the official press release from AVROBIO, Inc. related to the orphan drug designation status here.

How developing a treatment for a rare disease could lead to therapies for other, not-so-rare conditions

Logan Lacy, a child with AADC Deficiency: Photo courtesy Chambersburg Public Opinion

Tomorrow, the last day in February, is Rare Disease Day. It’s a day dedicated to raising awareness about rare diseases and the impact they have on patients and their families.

But the truth is rare diseases are not so rare. There are around 7,000 diseases that affect fewer than 200,000 Americans at any given time. In fact, it’s estimated that around one in 20 people will live with a rare disease at some point in their lives. Many may die from it.

This blog is about one man’s work to find a cure for one of those rare diseases, and how that could lead to a therapy for something that affects many millions of people around the world.

Dr. Krystof Bankiewicz; Photo courtesy Ohio State Medical Center

Dr. Krystof Bankiewicz is a brain surgeon at U.C. San Francisco and The Ohio State University. He is also the President and CEO at Brain Neurotherapy Bio and a world expert in delivering gene and other therapies to the brain. More than 20 years ago, he began trying to develop a treatment for Parkinson’s disease by looking at a gene responsible for AADC enzyme production, which plays an important role in the brain and central nervous system.  AADC is critical for the formation of serotonin and dopamine, chemicals that transmit signals between nerve cells, the latter of which plays a role in the development of Parkinson’s disease.

While studying the AADC enzyme, Dr. Bankiewicz learned of an extremely rare disorder where children lack the AADC enzyme that is critical for their development.  This condition significantly inhibits communication between the brain and the rest of the body, leading to extremely limited mobility, muscle spasms, and problems with overall bodily functions.  As a result of this, AADC deficient children require lifelong care, and particularly severe cases can lead to death in the first ten years of life.

“These children can’t speak. They have no muscle control, so they can’t do fundamental things such as walking, supporting their neck or lifting their arms,” says Dr. Bankiewicz. “They have involuntary movements, experience tremendously painful spasms almost like epileptic seizures. They can’t feed themselves and have to be fed through a tube in their stomach.”

So, Dr. Bankiewicz, building on his understanding of the gene that encodes AADC, developed an experimental approach to deliver a normal copy, injected directly into the midbrain, the area responsible for dopamine production. The DDC gene was inserted into a virus that acted as a kind of transport, carrying the gene into neurons, the brain cells affected by the condition. It was hoped that once inside, the gene would allow the body to produce the AADC enzyme and, in turn, enable it to produce its own dopamine .

And that’s exactly what happened.

“It’s unbelievable. In the first treated patients their motor system is dramatically improved, they are able to better control their movements, they can eat, they can sleep well. These are tremendous benefits. We have been following these children for almost three years post-treatment, and the progression we see doesn’t stop, it keeps going and we see these children keep on improving. Now they are able to get physical therapy to help them. Some are even able to go to school.”

For Dr. Bankiewicz this has been decades in the making, but that only makes it all the more gratifying: “This doesn’t happen very often in your lifetime, to be able to use all your professional experience and education to help people and see the impact it has on people’s lives.”

So far he has treated 20 patients from the US, UK and all over the world.

But he is far from finished.

Already the therapy has been given Orphan Drug Designation and Regenerative Medicine Advanced Therapy designation by the US Food and Drug Administration. The former is a kind of financial incentive to companies to develop drugs for rare diseases. The latter gives therapies that are proving to be both safe and effective, an accelerated path to approval for wider use. Dr. Bankiewicz hopes that will help them raise the funds needed to treat children with this rare condition.  “We want to make this affordable for families. We are not in this to make a profit; we want to get foundations and maybe even pharmaceutical companies to help us treat the kids, so they don’t have to cover the full costs themselves.”

CIRM has not funded any of this work, but the data and results from this research were important factors in our Board awarding Dr. Bankiewicz more than $5.5 million to begin a clinical trial for Parkinson’s disease. Dr. Bankiewicz is using a similar approach in that work to the one he has shown can help children with AADC deficiency.

While AADC deficiency may only affect a few hundred children worldwide, it’s estimated that Parkinson’s affects more than ten million people; one million of those in the US alone.  Developing this gene therapy technique in a rare disease, therefore, may ultimately benefit large populations of patients.

So, on this Rare Disease Day, we celebrate Dr. Bankiewicz and others whose compassion and commitment to finding treatments to help those battling rare conditions are helping change the world, one patient at a time.

You can follow the story of one child treated by Dr. Bankiewicz here.

Enabling the Best Choice for Patients: The Need for Effective Patient Navigation

Making sure patients get the treatment they need and not a “snake oil” substitute

We are at a turning point in regenerative medicine as the first wave of treatments have obtained FDA approval. But at the same time as we see the advance of scientifically rigorous research and regulated products we are also witnessing the continued proliferation of “unproven treatments.” This dueling environment can be overwhelming and distracting to individuals and families trying to manage life-threatening diseases.

How does a patient navigate this environment and get trusted and reliable information to help sort through their options?

CIRM teamed up with the CURA Foundation to organize a roundtable discussion intended to answer this question. The conversation included thought leaders involved in patient advocacy, therapy research and development, public policy and research funding. The roundtable was divided into three segments designed to discuss:

  1. Examples of state-of-the-art patient navigation systems,
  2. Policy, research and infrastructure needs required to expand navigation systems, and
  3. Communication needs for engaging patients and the broader community.

Examples of Navigation Systems:

This session was framed around the observation that patients often do not get the best medicines or treatments available for their condition. For example, in the area of cancer care there is evidence that the top 25% of cancers are not being treated optimally. Historic barriers to optimal treatment include cost pressures that may block access to treatments, lack of knowledge about the available treatments or the absence of experts in the location where the patient is being treated.  Much of the session focused on how these barriers are being overcome by partnerships between health care provides, employers and patients.

For example, new technologies such as DNA sequencing and other cell-based markers enable better diagnosis of a patient’s underlying disease. This information can be collected by a community hospital and shared with experts who work with the treating doctor to consider the best options for the patient. If patients need to access a specialty center for treatment, there are new models for the delivery of such care. Emphasis is placed on building a relationship with the patient and their family by surrounding them with a team that can address any questions that arise. The model of patient-centered care is being embraced by employers who are purchasing suites of services for their employees.

Patient advocacy groups have also supported efforts to get the best information about the patients’ underlying disease. Advocacy organizations have been building tools to connect patients with researchers with the aim of allowing secure and responsible sharing of medical information to drive the patient-centered development of new treatments. In a related initiative, the American Society of Hematology is creating a data hub for clinical trials for sickle cell disease. Collectively, these efforts are designed to accelerate new treatments by allowing critical data to be shared among researchers.

Essential Policy Infrastructure for Regenerative Medicine:

Session two dovetailed nicely with first discussion. There was continued emphasis on the need for additional evidence (data) to demonstrate that regenerative medicine treatments are having a significant effect on the patient’s disease. Various speakers echoed the need for patients in clinical trials to work with researchers to determine the benefits of treatments. Success stories with gene therapies in blood diseases were cited as proof of concept where treatments being evaluated in clinical trials are demonstrating a significant and sustained impact on diseases. Evidence of benefit is needed by both regulatory bodies that approve the treatments, such as the FDA, and by public and private payers / insurers that pay for treatments and patients that need to know the best option for their particular disease.

In addition, various speakers cited the continued proliferation of “unproven treatments” being marketed by for-profit centers. There was broad concern that the promotion of treatment where there is no evidence of effectiveness will mislead some patients and potentially harm the scientifically rigorous development of new treatments. Particularly for “stem cell” treatments, there was a desire to develop evaluation criteria that are clear and transparent to allow legitimate treatments to be distinguished from those with no evidence of effectiveness. One participant suggested there be a scorecard approach where specific treatments could be rated against specific indicators of safety, medical benefit and value in relation to alternative treatments. The idea would be to make this information widely available to patients, medical providers and the public to inform everything from medical decision making to advertising.

Communicating the Vision

The final session considered communication needs for the field of regenerative medicine. Patients and patient advocacy organizations described how they are using social media and other networking tools to share information and experiences in navigating their treatment options. Patient advocacy groups also described the challenges from providers of unproven treatments. In one case, a for profit “pop up” clinic had used the group’s videos in an attempt to legitimize their unproven treatment.

There was general consensus among the panelists that the field of regenerative medicine needs “trusted intermediaries” who can evaluate claims and help patients distinguish between high quality research and “snake oil”. These intermediaries should have the capacity to compile the most reliable evidence and utilize it to determine what options are available to patients. In addition, there needs to be shared decision making model where patients have the opportunity to explore options in an unbiased environment so they may make the best decision based on their specific needs and values.

Creating this kind of Navigation System will not be easy but the alternative is unacceptable. Too many vulnerable patients are being taken advantage of by the growing number of “predatory clinics” hawking expensive therapies that are both unproven and unapproved. We owe it to these patients to create a simple way for them to identify what are the most promising therapies, ones that have the highest chance of being both safe and effective. The roundtable discussion marked a starting point, bringing together many of the key players in the field, highlighting the key issues and beginning to identify possible solutions.

‘A Tornado at the Front Door, a Tsunami at the Back Door’

CIRM funds a lot of research and all of it has life-saving potential. But every once in a while you come across a story about someone benefiting from CIRM-supported research that highlights why the work we do is so important. This story is about a brilliant researcher at UC San Diego developing a treatment for a really rare disease, one that was unlikely to get funding from a big pharmaceutical company because it offered little chance for a return on its investment. At CIRM we don’t have to worry about things like that. Stories like this are our return on investment.

Our thanks to our colleagues at UCSD News for allowing us to run this piece in full.

Jordan Janz and Dr. Stephanie Cherqui in her lab at the UC San Diego School of Medicine: Photo courtesy UC San Diego

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By Heather Buschman, PhD

Born with a rare disease called cystinosis, 20-year-old Jordan Janz arrived at a crossroads: continue life as-is, toward a future most likely leading to kidney failure and an early death or become the first patient in the world to undergo a new gene-and-stem cell therapy developed over more than a decade by UC San Diego School of Medicine researchers

For the majority of Jordan Janz’s 20 years of life, most neighbors in his tiny Canadian town never knew he was sick. Janz snowboarded, hunted and fished. He hung with friends, often playing ice hockey video games. He worked in shipping and receiving for a company that makes oil pumps.

But there were times when Janz was younger that he vomited up to 13 times each day. He received a growth hormone injection every day for six years. He needed to swallow 56 pills every day just to manage his symptoms. And the medication required around-the-clock administration, which meant his mother or another family member had to get up with him every night.

“I was tired for school every day,” Janz said. “I was held back in second grade because I missed so much school. And because the medication had a bad odor to it, when I did go to school kids would ask, ‘What’s that smell?’ It was hard.”

Janz was born with cystinosis, a rare metabolic disorder that’s detected in approximately one in 100,000 live births worldwide. People with cystinosis inherit a mutation in the gene that encodes a protein called cystinosin. Cystinosin normally helps cells transport the amino acid cystine. Because cells in people with cystinosis don’t produce the cystinosin protein, cystine accumulates. Over the years, cystine crystals build up and begin to damage tissues and organs, from the kidneys and liver to muscles, eyes and brain. Numerous symptoms and adverse consequences result.

These days, Janz manages his condition. There’s a time-release version of the symptom-relieving medication now that allows him to go 12 hours between doses, allowing for a good night’s sleep. But there’s no stopping the relentless accumulation of cystine crystals, no cure for cystinosis.  

In October 2019, Janz became the first patient to receive treatment as part of a Phase I/II clinical trial to test the safety and efficacy of a unique gene therapy approach to treating cystinosis. The treatment was developed over more than a decade of research by Stephanie Cherqui, PhD, associate professor of pediatrics, and her team at University of California San Diego School of Medicine.

“The day they started looking for people for the trial, my mom picked up the phone, found a number for Dr. Cherqui, called her and put my name in as a candidate,” Janz said.

Janz’s mom, Barb Kulyk, has long followed Cherqui’s work. Like many parents of children with cystinosis, Kulyk has attended conferences, read up on research and met many other families, doctors and scientists working on the condition. Kulyk says she trusts Cherqui completely. But she was understandably nervous for her son to be the first person ever to undergo a completely new therapy.

“It’s like giving birth,” she said shortly before Janz received his gene therapy. “You’re really looking forward to the outcome, but dreading the process.”

The treatment

Cherqui’s gene therapy approach involves genetical modifying the patient’s own stem cells. To do this, her team obtained hematopoietic stem cells from Janz’s bone marrow. These stem cells are the precursors to all blood cells, including both red blood cells and immune cells. The scientists then re-engineered Janz’s stem cells in a lab using gene therapy techniques to introduce a normal version of the cystinosin gene. Lastly, they reinfused Janz with his own now-cystinosin-producing cells. The approach is akin to a bone marrow transplant — the patient is both donor and recipient.

“A bone marrow transplant can be very risky, especially when you take hematopoietic stem cells from a another person. In that case, there’s always the chance the donor’s immune cells will attack the recipient’s organs, so-called graft-versus-host disease,” Cherqui explained. “It’s a great advantage to use the patient’s own stem cells.”

As is the case for other bone marrow transplants, Janz’s gene-modified stem cells are expected to embed themselves in his bone marrow, where they should divide and differentiate to all types of blood cells. Those cells are then expected to circulate throughout his body and embed in his tissues and organs, where they should produce the normal cystinosin protein. Based on Cherqui’s preclinical data, she expects the cystinosin protein will be transferred to the surrounding diseased cells. At that point, Janz’s cells should finally be able to appropriately transport cystine for disposal — potentially alleviating his symptoms.

Before receiving his modified stem cells, Janz had to undergo chemotherapy to make space in his bone marrow for the new cells. Not unexpectedly, Janz experienced a handful of temporary chemotherapy-associated side-effects, including immune suppression, hair loss and fatigue. He also had mucositis, an inflammation of mucous membranes lining the digestive tract, which meant he couldn’t talk or eat much for a few days.

Now, only three months after his transfusion of engineered stem cells, Cherqui reports that Janz is making a good recovery, though it’s still too early to see a decrease in his cystinosis-related symptoms.

“I’ve been sleeping at least 10 hours a day for the last few weeks,” Janz said. “It’s crazy, but I know my body is just working hard to, I guess, create a new ‘me.’ So it’s no wonder I’m tired. But I’m feeling okay overall.

“One of the hardest parts for me is being inactive for so long. I’m not used to doing nothing all day. But I’m taking an online course while I wait for my immune system to rebuild. And I’m getting pretty good at video games.”

Like all Phase I/II clinical trials, the current study is designed to first test the safety and tolerability of the new treatment. Janz knows the treatment might not necessarily help him.

“When we started this trial, my mom explained it like this: ‘We have a tornado at the front door and a tsunami at the back door, and we have to pick one to go through. Neither will be any fun and we don’t know what’s going to happen, but you have to believe you will make it and go.

“So we weighed the pros and cons and, basically, if I don’t do this trial now, when I’m older I might not be healthy and strong enough for it. So I decided to go for it because, even if there are consequences from the chemotherapy, if it works I could live 20 years longer than I’m supposed to and be healthy for the rest of my life. That’s worth it.”

Besides the possible benefit to himself, Janz also sees his participation in the clinical trial as a way to contribute to the tight-knit community of families with children who have cystinosis.

“I’m willing to do if it helps the kids,” he said. “Somebody has to do it. I don’t have the money to donate to scientific conferences and stuff like that, but I can do this trial.”

The trial

If the treatment continues to meet certain criteria for safety and efficacy for Janz and one other participant after three months, two more adult participants will be enrolled. Three months after that, if the treatment continues to be safe and effective, the trial might enroll two adolescent participants. To participate in the clinical trial, individuals must meet specific eligibility requirements.

Later in the trial, Cherqui and team will begin measuring how well the treatment actually works. The specific objectives include assessing the degree to which gene-modified stem cells establish themselves in  bone marrow, how they affect cystine levels and cystine crystal counts in blood and tissues.

“This trial is the first to use gene-modified hematopoietic stem cell gene therapy to treat a multi-organ degenerative disorder for which the protein is anchored in the membrane of the lysosomes, as opposed to secreted enzymes,” Cherqui said. “We were amazed when we tested this approach in the mouse model of cystinosis — autologous stem cell transplantation reversed the disease. The tissues remained healthy, even the kidneys and the eyes.”

Trial participants are closely monitored for the first 100 days after treatment, then tested again at six, nine, 12, 18 and 24 months post-gene therapy for a variety of factors, including vital signs, cystine levels in a number of organs, kidney function, hormone function and physical well-being.

“If successful in clinical trials, this approach could provide a one-time, lifelong therapy that may prevent the need for kidney transplantation and long-term complications caused by cystine buildup,” Cherqui said.

The future

For the trial participants, all of the pre-treatment tests, the treatment itself, and monitoring afterward means a lot of travel to and long stays in San Diego.

It’s tough on Kulyk and Janz. They have to fly in from Alberta, Canada and stay in a San Diego hotel for weeks at a time. Kulyk has two older adult children, as well as a 12-year-old and a seven-year-old at home. 

“I’ve missed a lot of things with my other kids, but none of them seem to hold any grudges,” she said. “They seem to be totally fine and accepting. They’re like, ‘We’re fine, mom. You go and take care of Jordan.’”

Janz is looking forward to getting back home to his friends, his dog and his job, which provided him with paid leave while he received treatment and recovers.

For Cherqui, the search for a cystinosis cure is more than just a scientific exercise. Cherqui began working on cystinosis as a graduate student more than 20 years ago. At the time, she said, it was simply a model in which to study genetics and gene therapy.

“When you read about cystinosis, it’s just words. You don’t put a face to it. But after I met all the families, met the kids, and now that I’ve seen many of them grow up, and some of them die of the disease — now it’s a personal fight, and they are my family too.”

Patients with cystinosis typically experience kidney failure in their 20s, requiring kidney dialysis or transplantation for survival. For those born with cystinosis who make it into adulthood, the average lifespan is approximately 28 years old.

“I’m optimistic about this trial because it’s something we’ve worked so hard for and now it’s actually happening, and these families have so much hope for a better treatment,” Cherqui said. “After all the years of painstaking laboratory research, we now need to move into the clinic. If this works, it will be wonderful. If it doesn’t, we will all be disappointed but a least we’ll be able to say we tried.”

Nancy Stack, who founded the Cystinosis Research Foundation after her own daughter, Natalie, was diagnosed with the disease, calls Cherqui “the rock star of our community.”

“She cares deeply about the patients and is always available to talk, to explain her work and to give us hope,” Stack said. “She said years ago that she would never give up until she found the cure — and now we are closer to a cure than ever before.” (Read more about Natalie here.)

In addition to cystinosis, Cherqui says this type of gene therapy approach could also lead to treatment advancements for other multi-organ degenerative disorders, such as Friedreich’s ataxia and Danon disease, as well as other kidney, genetic and systemic diseases similar to cystinosis.

While they wait for the long-term results of the treatment, Kulyk is cautiously hopeful.

“Moms are used to being able to fix everything for their children — kiss boo-boos make them better, make cupcakes for school, whip up Halloween costumes out of scraps, pull a coveted toy out of thin air when it has been sold out for months.

“But we have not been able to fix this, to take it away. I not only want this disease gone for my child, I want cystinosis to be nothing more than a memory for all the children and adults living with it. I know that even if and when Jordan is cured, there will still be so much work to do, in terms of regulatory approvals and insurance coverage.

“Having hope for your child’s disease to be cured is a slippery slope. We have all been there, held hope in our hands and had to let go. But, I find myself in a familiar place, holding onto hope again and this time I am not letting go.”

Video of Dr. Cherqui and Jordan Janz talking about the therapy

For more information about the Phase I/II clinical trial for cystinosis and to learn how to enroll, call 1-844-317-7836 or email alphastemcellclinic@ucsd.edu.

Cherqui’s research has been funded by the Cystinosis Research Foundation, California Institute for Regenerative Medicine (CIRM), and National Institutes of Health. She receives additional support from the Sanford Stem Cell Clinical Center and CIRM-funded Alpha Stem Cell Clinic at UC San Diego Health, and AVROBIO.

Stem Cell/Gene Therapy combo heals patients battling rare disorder

Brenden Whittaker and his dog: Photo by Colin McGuire

A few years ago, Brenden Whittaker was running out of time. Brenden was born with a rare condition called x-linked chronic granulomatous disease or XCGD. It meant he lacked a critical part of his immune system that protects against bacterial or fungal infections.

Over 22 years Brenden was in and out of the hospital hundreds of times. Twice he almost died. When antibiotics failed to clear up persistent infections surgeons had to remove parts of his lungs and liver.

Brenden felt he was running out of options. Then he signed up for a clinical trial (funded by CIRM) that would use his own stem cells to correct the problem. More than four years later Brenden is doing just fine.

And he’s not the only one. A new study, published in the journal Nature Medicine, shows that six other patients in the clinical trial are now in remission and have stopped taking any other medications.

Dr. Don Kohn: Photo courtesy UCLA

Don Kohn, the lead researcher on the team from UCLA’s Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, says that in the past the only “cure” for people with CGD was a bone marrow transplant, but that was rarely an option for most patients. In a news release he said finding a perfect match for a transplant was difficult, and even then, patients had to take powerful anti-rejection medications to stop their body rejecting the transplant. So, they developed another approach, using genetically re-engineered stem cells from the patient themselves.

“With this gene therapy, you can use a patient’s own stem cells instead of donor cells for a transplant. This means the cells are perfectly matched to the patient and it should be a much safer transplant, without the risks of rejection.”

The team removed blood stem cells from the patients and, in the lab, corrected the genetic mutation that caused CGD. They then returned those cells to the patients which, because they are stem cells, multiplied and created a new blood supply – one free of CGD – and repaired the immune system.

Brenden was the first of five patients treated in the US. Another four were treated in Europe. All were between the ages of 2 and 27 (CGD patients often die in their 20’s because of the impact of repeated infections).

  • Two patients died because of previously incurred infections
  • Six of the seven surviving patients have discontinued previous treatments
  • Four new patients have since been treated and are currently free of infections

Dr. Kohn said the results are really encouraging: “None of the patients had complications that you might normally see from donor cells and the results were as good as you’d get from a donor transplant — or better.”

The next step is for the researchers to work with the US Food and Drug Administration to get permission to carry out a larger trial, with the eventual goal of getting approval to make it available to all patients who need it.  

Regular readers of our blog will remember that Don Kohn also pioneered a similar approach in treating, and curing, children battling another rare immune disorder, severe combined immunodeficiency or SCID. You can read about that here.

As for Brenden, he is now in college and has his sights set on medical school. In 2016 we profiled him in our Annual Report and ran a long interview with him on the blog where he talked about the joys of mowing the lawn and learning to live without a deadly disease stalking him.

Dashed Dreams and New Hope: A Quest to Cure Thymic Deficiency

By Kelly Shepard, PhD., CIRM’s Associate Director, Discovery & Translation

CIRM has previously blogged about advances in treating certain forms of  “bubble baby” disease”, where a person is born with a defect in their blood forming stem cells that results in a deficient immune system, rendering them vulnerable to lethal infections by all manner of bacteria, virus or germ.

If a suitable donor can be found, or if the patient’s own defective cells can be corrected through gene therapy approaches, it is now possible to treat or cure such disorders through a bone marrow transplant. In this procedure, healthy blood stem cells are infused into the patient, taking up residence in his or her bone marrow and dividing to give rise to functioning immune cells such as T cells and B cells.

Unfortunately, there is another type of “bubble baby” disease that cannot be treated by providing healthy blood stem cells, because the defective immune system is caused by a different culprit altogether- a missing or dysfunctional thymus.

Created for the National Cancer Institute, http://www.cancer.gov

T Cells Go to School

What is a thymus?  Most of us give little thought to this leaf-shaped organ, which is large and important in our early childhoods, but becomes small and inconspicuous as we age. This transformation belies the critical role a thymus plays in the development of our adaptive immune systems, which takes place in our youth: to prepare our bodies to fight infections for the rest of our lives.

One might think of the thymus as a “school”, where immature T cells go to “learn” how to recognize and attack foreign antigens (surface markers), such as those found on microorganisms or tissues from other individuals. The thymus also “teaches” our immune system to distinguish “self” from “other” by eliminating any T cells that attack our own tissues. Without this critical function, our immune system could inadvertently turn against us, causing serious autoimmune disorders such as ulcerative colitis and myasthenia gravis.

Many children with a severely deficient or absent thymus, referred to as athymia, have inherited a chromosome that is missing a key stretch of genes on a region called 22q11. Doctors believe perhaps 1/2000-1/4000 babies are born with some type of deletion in this region, which leads to a variable spectrum of disorders called 22q11 syndrome that can affect just about any part of the body, and can even cause learning disabilities and mental illness.

Individuals with one form of 22q11, called DiGeorge Syndrome, are particularly affected in the heart, thymus, and parathyroid glands. In the United States, about 20 infants are born per year with the “complete” and most severe form of DiGeorge Syndrome, who lack a thymus altogether, and have severely depressed numbers of T cells for fighting infections. Without medical intervention, this condition is usually fatal by 24 months of age.

Optimism and Setback                                                                  

Although there are no therapies approved by the Food and Drug Administration (FDA) for pediatric athymia, Dr. Mary Louise Markert at Duke University and Enzyvant, Inc. have been pioneering an experimental approach to treat children with complete DiGeorge syndrome.

In this procedure, discarded thymic tissues are collected from infants undergoing cardiac surgery, where some of the thymus needs to be removed in order for the surgeon to gain access to the heart. These tissues are processed to remove potentially harmful donor T cells and then transplanted into the thigh of an athymic DiGeorge patient.

Results from early clinical trials seemed promising, with more than 70% of patients surviving, including several who are now ten years post-transplant. Based on those results, in June of 2019 Enzyvant applied to the FDA for a Biologics License Application (BLA), which is needed to be able to sell the therapy in the US. Unfortunately, only a few months later, Enzyvant announced that the FDA had declined to approve the BLA due to manufacturing concerns.

While it may be possible to address these issues in time, the need to step back to the drawing board was a devastating blow to the DiGeorge Community, who have waited decades for a promising treatment to emerge on the horizon.

New Opportunities

Despite the setback, there is reason to hope. In early 2019, CIRM granted a “Quest” Award to team of investigators at Stanford University to develop a novel stem cell based approach for treating thymic deficiency. Co-led by Katja Weinacht, a pediatric hematologist/oncologist, and Vittorio Sebastiano, a stem cell expert and developmental biologist, the team’s strategy is to coax induced pluripotent stem cells (iPS) in the laboratory to differentiate into thymic tissue, which could then be transplanted into patients using the route pioneered by Duke and Enzyvant.

Katja Weinacht: Photo courtesy Stanford Children’s Health

The beauty of this new approach is that pluripotent stem cells are essentially immortal in culture, providing an inexhaustible supply of fresh thymic cells for transplant, thereby allowing greater control over the quality and consistency of donor tissues. A second major advantage is the possibility of using pluripotent cells from the patient him/herself as the source, which should be perfectly immune-matched and alleviate the risk of rejection and autoimmunity that comes with use of donated tissues.

Vittorio Sebastiano: Photo courtesy Stanford

Sounds easy, so what are the challenges? As with many regenerative medicine approaches, the key is getting a pluripotent stem cell to differentiate into the right type of cells in the lab, which is a very different environment than what cells experience naturally when they develop in the context of an embryo and womb, where many cells are interacting and providing complex, instructive cues to one another. The precise factors and timing all need to be worked out and in most cases, this is done with an incomplete knowledge of human development.

A second challenge relates to using cells from DiGeorge patients to produce thymic tissue, which are missing several genes on their 22nd chromosome and will likely require sophisticated genetic engineering to restore this ability.

Fortunately, Drs. Weinacht and Sebastiano are up to the challenge, and have already made progress in differentiating human induced pluripotent stem cells (iPS) into thymic lineage intermediates that appear to be expressing the right proteins at the right time. They plan to combine these cells with engineered materials to create a three-dimensional (3D) tissue that more closely resembles an authentic organ, and which can be tested for functionality in athymic mice.

There is more work to be done, but these advances, along with continued technological improvements and renewed efforts from Enzyvant, could forge a path to the clinic and  lead to a brighter future for patients suffering from congenital athymia and other forms of thymic dysfunction.

 

The Top CIRM Blogs of 2019

This year the most widely read blog was actually one we wrote back in 2018. It’s the transcript of a Facebook Live: “Ask the Stem Cell Team” event about strokes and stroke recovery. Because stroke is the third leading cause of death and disability in the US it’s probably no surprise this blog has lasting power. So many people are hoping that stem cells will help them recover from a stroke.

But of the blogs that we wrote and posted this year there’s a really interesting mix of topics.

The most read 2019 blog was about a potential breakthrough in the search for a treatment for type 1 diabetes (T1D).  Two researchers at UC San Francisco, Dr. Matthias Hebrok and Dr. Gopika Nair developed a new method of replacing the insulin-producing cells in the pancreas that are destroyed by type 1 diabetes. 

Dr. Matthias Hebrok
Dr. Gopika Nair

Dr. Hebrok described it as a big advance saying: “We can now generate insulin-producing cells that look and act a lot like the pancreatic beta cells you and I have in our bodies. This is a critical step towards our goal of creating cells that could be transplanted into patients with diabetes.”

It’s not too surprising a blog about type 1 diabetes was at the top. This condition affects around 1.25 million Americans, a huge audience for any potential breakthrough. However, the blog that was the second most read is the exact opposite. It is about a rare disease called cystinosis. How rare? Well, there are only around 500 children and young adults in the US, and just 2,000 worldwide diagnosed with this condition.  

It might be rare but its impact is devastating. A genetic mutation means children with this condition lack the ability to clear an amino acid – cysteine – from their body. The buildup of cysteine leads to damage to the kidneys, eyes, liver, muscles, pancreas and brain.

Dr. Stephanie Cherqui

UC San Diego researcher Dr. Stephanie Cherqui and her team are taking the patient’s own blood stem cells and, in the lab, genetically re-engineering them to correct the mutation, then returning the cells to the patient. It’s hoped this will create a new, healthy blood system free of the disease.

Dr. Cherqui says if it works, this could help not just people with cystinosis but a wide array of other disorders: “We were thrilled that the stem cells and gene therapy worked so well to prevent tissue degeneration in the mouse model of cystinosis. This discovery opened new perspectives in regenerative medicine and in the application to other genetic disorders. Our findings may deliver a completely new paradigm for the treatment of a wide assortment of diseases including kidney and other genetic disorders.”

Sickled cells

The third most read blog was about another rare disease, but one that has been getting a lot of media attention this past year. Sickle cell disease affects around 100,000 Americans, mostly African Americans. In November the Food and Drug Administration (FDA) approved Oxbryta, a new therapy that reduces the likelihood of blood cells becoming sickle shaped and clumping together – causing blockages in blood vessels.

But our blog focused on a stem cell approach that aims to cure the disease altogether. In many ways the researchers in this story are using a very similar approach to the one Dr. Cherqui is using for cystinosis. Genetically correcting the mutation that causes the problem, creating a new, healthy blood system free of the sickle shaped blood cells.

Two other blogs deserve honorable mentions here as well. The first is the story of James O’Brien who lost the sight in his right eye when he was 18 years old and now, 25 years later, has had it restored thanks to stem cells.

The fifth most popular blog of the year was another one about type 1 diabetes. This piece focused on the news that the CIRM Board had awarded more than $11 million to Dr. Peter Stock at UC San Francisco for a clinical trial for T1D. His approach is transplanting donor pancreatic islets and parathyroid glands into patients, hoping this will restore the person’s ability to create their own insulin and control the disease.

2019 was certainly a busy year for CIRM. We are hoping that 2020 will prove equally busy and give us many new advances to write about. You will find them all here, on The Stem Cellar.

The podcast that sounds like a science thriller but for the patients involved is all too real

Laura Beil, writer and producer of the Bad Batch podcast

As we get close to the end of the year there is no shortage of lists of the “best of the year” and even this year the “best of the decade”. But when it comes to podcasts it would be hard to think of a better one than “Bad Batch”. It’s part stem cell research, part medical mystery and altogether engrossing.

It’s the work of Laura Beil, an award-winning journalist who follows the trail of a stem cell therapy that was supposed to help patients but instead left them battling life-threatening infections. It highlights how some clinics are able to find loopholes in the law that allow them to offer unproven and unapproved therapies, and how those therapies can put people’s lives at risk.

We have written about the dangers of predatory stem cell clinics several times, but in “Bad Batch” you get to hear the voices of the people affected, and ultimately the people responsible. It’s great journalism and fascinating story telling. And it’s a reminder of the work that needs to be done to stop this ever happening again.

Facebook Live: Ask the Stem Cell Team

On December 12th we hosted our latest ‘Facebook Live: Ask the Stem Cell Team’ event. This time around we really did mean team. We had a host of our Science Officers answering questions from friends and supporters of CIRM. We got a lot of questions and didn’t have enough time to address them all. So here’s answers to all the questions.

What are the obstacles to using partial cellular reprogramming to return people’s entire bodies to a youthful state. Paul Hartman.  San Leandro, California

Dr. Kelly Shepard

Dr. Kelly Shepard: Certainly, scientists have observed that various manipulations of cells, including reprogramming, partial reprogramming, de-differentiation and trans-differentiation, can restore or change properties of cells, and in some cases, these changes can reflect a more “youthful” state, such as having longer telomeres, better proliferative capacity, etc. However, some of these same rejuvenating properties, outside of their normal context, could be harmful or deadly, for example if a cell began to grow and divide when or where it shouldn’t, similar to cancer. For this reason, I believe the biggest obstacles to making this approach a reality are twofold: 1)  our current, limited understanding of the nature of partially reprogrammed cells; and 2) our inability to control the fate of those cells that have been partially reprogrammed, especially if they are inside a living organism.  Despite the challenges, I think there will be step wise advances where these types of approaches will be applied, starting with specific tissues. For example, CIRM has recently funded an approach that uses reprogramming to make “rejuvenated” versions of T cells for fighting lung cancer.  There is also a lot of interest in using such approaches to restore the reparative capacity of aged muscle. Perhaps some successes in these more limited areas will be the basis for expanding to a broader use.

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STROKE

What’s going on with Stanford’s stem cell trials for stroke? I remember the first trial went really well In 2016 have not heard anything about since? Elvis Arnold

Dr. Lila Collins

Dr. Lila Collins: Hi Elvis, this is an evolving story.  I believe you are referring to SanBio’s phase 1/2a stroke trial, for which Stanford was a site. This trial looked at the safety and feasibility of SanBio’s donor or allogeneic stem cell product in chronic stroke patients who still had motor deficits from their strokes, even after completing physical therapy when natural recovery has stabilized.  As you note, some of the treated subjects had promising motor recoveries. 

SanBio has since completed a larger, randomized phase 2b trial in stroke, and they have released the high-level results in a press release.  While the trial did not meet its primary endpoint of improving motor deficits in chronic stroke, SanBio conducted a very similar randomized trial in patients with stable motor deficits from chronic traumatic brain injury (TBI).  In this trial, SanBio saw positive results on motor recovery with their product.  In fact, this product is planned to move towards a conditional approval in Japan and has achieved expedited regulatory status in the US, termed RMAT, in TBI which means it could be available more quickly to patients if all goes well.  SanBio plans to continue to investigate their product in stroke, so I would stay tuned as the work unfolds. 

Also, since you mentioned Stanford, I should note that Dr Gary Steinberg, who was a clinical investigator in the SanBio trial you mentioned, will soon be conducting a trial with a different product that he is developing, neural progenitor cells, in chronic stroke.  The therapy looks promising in preclinical models and we are hopeful it will perform well for patients in the clinic.

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I am a stroke survivor will stem cell treatment able to restore my motor skills? Ruperto

Dr. Lila Collins:

Hi Ruperto. Restoring motor loss after stroke is a very active area of research.  I’ll touch upon a few ongoing stem cell trials.  I’d just like to please advise that you watch my colleague’s comments on stem cell clinics (these can be found towards the end of the blog) to be sure that any clinical research in which you participate is as safe as possible and regulated by FDA.

Back to stroke, I mentioned SanBio’s ongoing work to address motor skill loss in chronic stroke earlier.  UK based Reneuron is also conducting a phase 2 trial, using a neural progenitor cell as a candidate therapy to help recover persistent motor disability after stroke (chronic).  Dr Gary Steinberg at Stanford is also planning to conduct a clinical trial of a human embryonic stem cell-derived neuronal progenitor cell in stroke.

There is also promising work being sponsored by Athersys in acute stroke. Athersys published results from their randomized, double blinded placebo controlled Ph2 trial of their Multistem product in patients who had suffered a stroke within 24-48 hours.  After intravenous delivery, the cells improved a composite measure of stroke recovery, including motor recovery.  Rather than acting directly on the brain, Multistem seems to work by traveling to the spleen and reducing the inflammatory response to a stroke that can make the injury worse.

Athersys is currently recruiting a phase 3 trial of its Multistem product in acute stroke (within 1.5 days of the stroke).  The trial has an accelerated FDA designation, called RMAT and a special protocol assessment.  This means that if the trial is conducted as planned and it reaches the results agreed to with the FDA, the therapy could be cleared for marketing.  Results from this trial should be available in about two years. 

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Questions from several hemorrhagic stroke survivors who say most clinical trials are for people with ischemic strokes. Could stem cells help hemorrhagic stroke patients as well?

Dr. Lila Collins:

Regarding hemorrhagic stroke, you are correct the bulk of cell therapies for stroke target ischemic stroke, perhaps because this accounts for the vast bulk of strokes, about 85%.

That said, hemorrhagic strokes are not rare and tend to be more deadly.  These strokes are caused by bleeding into or around the brain which damages neurons.  They can even increase pressure in the skull causing further damage.  Because of this the immediate steps treating these strokes are aimed at addressing the initial bleeding insult and the blood in the brain.

While most therapies in development target ischemic stroke, successful therapies developed to repair neuronal damage or even some day replace lost neurons, could be beneficial after hemorrhagic stroke as well.

We are aware of a clinical trial targeting acute hemorrhagic stroke that is being run by the Mayo clinic in Jacksonville Florida.

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I had an Ischemic stroke in 2014, and my vision was also affected. Can stem cells possibly help with my vision issues. James Russell

Dr. Lila Collins:

Hi James. Vision loss from stroke is complex and the type of loss depends upon where the stroke occurred (in the actual eye, the optic nerve or to the other parts of the brain controlling they eye or interpreting vision).  The results could be:

  1. Visual loss from damage to the retina
  2. You could have a normal eye with damage to the area of the brain that controls the eye’s movement
  3. You could have damage to the part of the brain that interprets vision.

You can see that to address these various issues, we’d need different cell replacement approaches to repair the retina or the parts of the brain that were damaged. 

Replacing lost neurons is an active effort that at the moment is still in the research stages.  As you can imagine, this is complex because the neurons have to make just the right connections to be useful. 

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VISION

Is there any stem cell therapy for optical nerve damage? Deanna Rice

Dr. Ingrid Caras

Dr. Ingrid Caras: There is currently no proven stem cell therapy to treat optical nerve damage, even though there are shady stem cell clinics offering treatments.  However, there are some encouraging early gene therapy studies in mice using a virus called AAV to deliver growth factors that trigger regeneration of the damaged nerve. These studies suggest that it may be possible to restore at least some visual function in people blinded by optic nerve damage from glaucoma

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I read an article about ReNeuron’s retinitis pigmentosa clinical trial update.  In the article, it states: “The company’s treatment is a subretinal injection of human retinal progenitors — cells which have almost fully developed into photoreceptors, the light-sensing retinal cells that make vision possible.” My question is: If they can inject hRPC, why not fully developed photoreceptors? Leonard

Dr. Kelly Shepard: There is evidence from other studies, including from other tissue types such as blood, pancreas, heart and liver, that fully developed (mature) cell types tend not to engraft as well upon transplantation, that is the cells do not establish themselves and survive long term in their new environment. In contrast, it has been observed that cells in a slightly less “mature” state, such as those in the progenitor stage, are much more likely to establish themselves in a tissue, and then differentiate into more mature cell types over time. This question gets at the crux of a key issue for many new therapies, i.e. what is the best cell type to use, and the best timing to use it.

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My question for the “Ask the Stem Cell Team” event is: When will jCyte publish their Phase IIb clinical trial results. Chris Allen

Dr. Ingrid Caras: The results will be available sometime in 2020.

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I understand the hRPC cells are primarily neurotropic (rescue/halt cell death); however, the literature also says hRPC can become new photoreceptors.  My questions are: Approximately what percentage develop into functioning photoreceptors? And what percentage of the injected hRPC are currently surviving? Leonard Furber, an RP Patient

Dr. Kelly Shepard: While we can address these questions in the lab and in animal models, until there is a clinical trial, it is not possible to truly recreate the environment and stresses that the cells will undergo once they are transplanted into a human, into the site where they are expected to survive and function. Thus, the true answer to this question may not be known until after clinical trials are performed and the results can be evaluated. Even then, it is not always possible to monitor the fate of cells after transplantation without removing tissues to analyze (which may not be feasible), or without being able to transplant labeled cells that can be readily traced.

Dr. Ingrid Caras – Although the cells have been shown to be capable of developing into photoreceptors, we don’t know if this actually happens when the cells are injected into a patient’s eye.   The data so far suggest that the cells work predominantly by secreting growth factors that rescue damaged retinal cells or even reverse the damage. So one possible outcome is that the cells slow or prevent further deterioration of vision. But an additional possibility is that damaged retinal cells that are still alive but are not functioning properly may become healthy and functional again which could result in an improvement in vision.

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DIABETES

What advances have been made using stem cells for the treatment of Type 2 Diabetes? Mary Rizzo

Dr. Ross Okamura

Dr. Ross Okamura: Type 2 Diabetes (T2D) is a disease where the body is unable to maintain normal glucose levels due to either resistance to insulin-regulated control of blood sugar or insufficient insulin production from pancreatic beta cells.  The onset of disease has been associated with lifestyle influenced factors including body mass, stress, sleep apnea and physical activity, but it also appears to have a genetic component based upon its higher prevalence in certain populations. 

Type 1 Diabetes (T1D) differs from T2D in that in T1D patients the pancreatic beta cells have been destroyed by the body’s immune system and the requirement for insulin therapy is absolute upon disease onset rather than gradually developing over time as in many T2D cases.  Currently the only curative approach to alleviate the heavy burden of disease management in T1D has been donor pancreas or islet transplantation. However, the supply of donor tissue is small relative to the number of diabetic patients.  Donor islet and pancreas transplants also require immune suppressive drugs to prevent allogenic immune rejection and the use of these drugs carry additional health concerns.  However, for some patients with T1D, especially those who may develop potentially fatal hypoglycemia, immune suppression is worth the risk.

To address the issue of supply, there has been significant activity in stem cell research to produce insulin secreting beta cells from pluripotent stem cells and recent clinical data from Viacyte’s CIRM funded trial indicates that implanted allogeneic human stem cell derived cells in T1D patients can produce circulating c-peptide, a biomarker for insulin.  While the trial is not designed specifically to cure insulin-dependent T2D patients, the ability to produce and successfully engraft stem cell-derived beta cells would be able to help all insulin-dependent diabetic patients.

It’s also worth noting that there is a sound scientific reason to clinically test a patient-derived pluripotent stem cell-based insulin-producing cells in insulin-dependent T2D diabetic patients; the cells in this case could be evaluated for their ability to cure diabetes in the absence of needing to prevent both allogeneic and autoimmune responses.

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SPINAL CORD INJURY

Is there any news on clinical trials for spinal cord injury? Le Ly

Kevin McCormack: The clinical trial CIRM was funding, with Asterias (now part of a bigger company called Lineage Cell Therapeutics, is now completed and the results were quite encouraging. In a news release from November of 2019 Brian Culley, CEO of Lineage Cell Therapeutics, described the results this way.

“We remain extremely excited about the potential for OPC1 (the name of the therapy used) to provide enhanced motor recovery to patients with spinal cord injuries. We are not aware of any other investigative therapy for SCI (spinal cord injury) which has reported as encouraging clinical outcomes as OPC1, particularly with continued improvement beyond 1 year. Overall gains in motor function for the population assessed to date have continued, with Year 2 assessments measuring the same or higher than at Year 1. For example, 5 out of 6 Cohort 2 patients have recovered two or more motor levels on at least one side as of their Year 2 visit whereas 4 of 6 patients in this group had recovered two motor levels as of their Year 1 visit. To put these improvements into perspective, a one motor level gain means the ability to move one’s arm, which contributes to the ability to feed and clothe oneself or lift and transfer oneself from a wheelchair. These are tremendously meaningful improvements to quality of life and independence. Just as importantly, the overall safety of OPC1 has remained excellent and has been maintained 2 years following administration, as measured by MRI’s in patients who have had their Year 2 follow-up visits to date. We look forward to providing further updates on clinical data from SCiStar as patients continue to come in for their scheduled follow up visits.”

Lineage Cell Therapeutics plans to meet with the FDA in 2020 to discuss possible next steps for this therapy.

In the meantime the only other clinical trial I know that is still recruiting is one run by a company called Neuralstem. Here is a link to information about that trial on the www.clinicaltrials.gov website.

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ALS

Now that the Brainstorm ALS trial is finished looking for new patients do you have any idea how it’s going and when can we expect to see results? Angela Harrison Johnson

Dr. Ingrid Caras: The treated patients have to be followed for a period of time to assess how the therapy is working and then the data will need to be analyzed.  So we will not expect to see the results probably for another year or two.

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AUTISM

Are there treatments for autism or fragile x using stem cells? Magda Sedarous

Dr. Kelly Shepard: Autism and disorders on the autism spectrum represent a collection of many different disorders that share some common features, yet have different causes and manifestations, much of which we still do not understand. Knowing the origin of a disorder and how it affects cells and systems is the first step to developing new therapies. CIRM held a workshop on Autism in 2009 to brainstorm potential ways that stem cell research could have an impact. A major recommendation was to exploit stem cells and new technological advances to create cells and tissues, such as neurons, in the lab from autistic individuals that could then be studied in great detail.  CIRM followed this recommendation and funded several early-stage awards to investigate the basis of autism, including Rett Syndrome, Fragile X, Timothy Syndrome, and other spectrum disorders. While these newer investigations have not yet led to therapies that can be tested in humans, this remains an active area of investigation. Outside of CIRM funding, we are aware of more mature studies exploring the effects of umbilical cord blood or other specific stem cell types in treating autism, such as an ongoing clinical trial conducted at Duke University.

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PARKINSON’S DISEASE

What is happening with Parkinson’s research? Hanifa Gaphoor

Dr. Kent Fitzgerald

Dr. Kent Fitzgerald: Parkinson’s disease certainly has a significant amount of ongoing work in the regenerative medicine and stem cell research. 

The nature of cell loss in the brain, specifically the dopaminergic cells responsible for regulating the movement, has long been considered a good candidate for cell replacement therapy.  

This is largely due to the hypothesis that restoring function to these cells would reverse Parkinson’s symptoms. This makes a lot of sense as front line therapy for the disease for many years has been dopamine replacement through L-dopa pills etc.  Unfortunately, over time replacing dopamine through a pill loses its benefit, whereas replacing or fixing the cells themselves should be a more permanent fix. 

Because a specific population of cells in one part of the brain are lost in the disease, multiple labs and clinicians have sought to replace or augment these cells by transplantation of “new” functional cells able to restore function to the area an theoretically restore voluntary motor control to patients with Parkinson’s disease. 

Early clinical research showed some promise, however also yielded mixed results, using fetal tissue transplanted into the brains of Parkinson’s patients.   As it turns out, the cell types required to restore movement and avoid side effects are somewhat nuanced.  The field has moved away from fetal tissue and is currently pursuing the use of multiple stem cell types that are driven to what is believed to be the correct subtype of cell to repopulate the lost cells in the patient. 

One project CIRM sponsored in this area with Jeanne Loring sought to develop a cell replacement therapy using stem cells from the patients themselves that have been reprogrammed into the kinds of cell damaged by Parkinson’s.  This type of approach may ultimately avoid issues with the cells avoiding rejection by the immune system as can be seen with other types of transplants (i.e. liver, kidney, heart etc).

Still, others are using cutting edge gene therapy technology, like the clinical phase project CIRM is sponsoring with Krystof Bankiewicz to investigate the delivery of a gene (GDNF) to the brain that may help to restore the activity of neurons in the Parkinson’s brain that are no longer working as they should. 

The bulk of the work in the field of PD at the present remains centered on replacing or restoring the dopamine producing population of cells in the brain that are affected in disease.   

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HUNTINGTON’S DISEASE

Any plans for Huntington’s? Nikhat Kuchiki

Dr. Lisa Kadyk

Dr. Lisa Kadyk: The good news is that there are now several new therapeutic approaches to Huntington’s Disease that are at various stages of preclinical and clinical development, including some that are CIRM funded.   One CIRM-funded program led by Dr. Leslie Thompson at UC Irvine is developing a cell-based therapeutic that consists of neural stem cells that have been manufactured from embryonic stem cells.   When these cells are injected into the brain of a mouse that has a Huntington’s Disease mutation, the cells engraft and begin to differentiate into new neurons.  Improvements are seen in the behavioral and electrophysiological deficits in these mutant mice, suggesting that similar improvements might be seen in people with the disease.   Currently, CIRM is funding Dr. Thompson and her team to carry out rigorous safety studies in animals using these cells, in preparation for submitting an application to the FDA to test the therapy in human patients in a clinical trial.   

There are other, non-cell-based therapies also being tested in clinical trials now, using  anti-sense oligonucleotides (Ionis, Takeda) to lower the expression of the Huntington protein.  Another HTT-lowering approach is similar – but uses miRNAs to lower HTT levels (UniQure, Voyager)

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TRAUMATIC BRAIN INJURY (TBI)

My 2.5 year old son recently suffered a hypoxic brain injury resulting in motor and speech disabilities. There are several clinical trials underway for TBI in adults. My questions are:

  • Will the results be scalable to pediatric use and how long do you think it would take before it is available to children?
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  • I’m wondering why the current trials have chosen to go the route of intracranial injections as opposed to something slightly less invasive like an intrathecal injection?
  • Is there a time window period in which stem cells should be administered by, after which the administration is deemed not effective?

Dr. Kelly Shepard:  TBI and other injuries of the nervous system are characterized by a lot of inflammation at the time of injury, which is thought to interfere with the healing process- and thus some approaches are intended to be delivered after that inflammation subsides. However, we are aware of approaches that intend to deliver a therapy to a chronic injury, or one that has occurred  previously. Thus, the answer to this question may depend on how the intended therapy is supposed to work. For example, is the idea to grow new neurons, or is it to promote the survival of neurons of other cells that were spared by the injury? Is the therapy intended to address a specific symptom, such as seizures? Is the therapy intended to “fill a gap” left behind after inflammation subsides, which might not restore all function but might ameliorate certain symptoms.? There is still a lot we don’t understand about the brain and the highly sophisticated network of connections that cannot be reversed by only replacing neurons, or only reducing inflammation, etc. However, if trials are well designed, they should yield useful information even if the therapy is not as effective as hoped, and this information will pave the way to newer approaches and our technology and understanding evolves.

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We have had a doctor recommending administering just the growth factors derived from MSC stem cells. Does the science work that way? Is it possible to isolate the growth factors and boost the endogenous growth factors by injecting allogenic growth factors?

Dr. Stephen Lin

Dr. Stephen Lin:  Several groups have published studies on the therapeutic effects in non-human animal models of using nutrient media from MSC cultures that contain secreted factors, or extracellular vesicles from cells called exosomes that carry protein or nucleic acid factors.  Scientifically it is possible to isolate the factors that are responsible for the therapeutic effect, although to date no specific factor or combination of factors have been identified to mimic the effects of the undefined mixtures in the media and exosomes.  At present no regulatory approved clinical therapy has been developed using this approach. 

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PREDATORY STEM CELL CLINICS

What practical measures are being taken to address unethical practitioners whose bad surgeries are giving stem cell advances a bad reputation and are making forward research difficult? Kathy Jean Schultz

Dr. Geoff Lomax

Dr. Geoff Lomax: Terrific question! I have been doing quite a bit research into the history of this issue of unethical practitioners and I found an 1842 reference to “quack medicines.” Clearly this is nothing new. In that day, the author appealed to make society “acquainted with the facts.”

In California, we have taken steps to (1) acquaint patients with the facts about stem cell treatments and (2) advance FDA authorized treatments for unmet medical needs.

  • First, CIRM work with Senator Hernandez in 2017 to write a law the requires provides to disclose to patient that a stem cell therapy has not been approved by the Food and Drug administration.
  • We continue to work with the State Legislature and Medical Board of California to build on policies that require accurate disclosure of the facts to patients.
  • Second, our clinical trial network the — Alpha Stem Cell Clinics – have supported over 100 FDA-authorized clinical trials to advance responsible clinical research for unmet medical needs.

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I’m curious if adipose stem cell being used at clinics at various places in the country is helpful or beneficial? Cheri Hicks

Adipose tissue has been widely used particularly in plastic and reconstructive surgery. Many practitioners suggest adipose cells are beneficial in this context. With regard to regenerative medicine and / or the ability to treat disease and injury, I am not aware of any large randomized clinical trials that demonstrate the safety and efficacy of adipose-derived stem cells used in accordance with FDA guidelines.

I went to a “Luncheon about Stem Cell Injections”. It sounded promising. I went thru with it and got the injections because I was desperate from my knee pain. The price of stem cell injections was $3500 per knee injection. All went well. I have had no complications, but haven’t noticed any real major improvement, and here I am a year later. My questions are:

 1) I wonder on where the typical injection cells are coming from?

  2) I wonder what is the actual cost of the cells?

3) What kind of results are people getting from all these “pop up” clinics or established clinics that are adding this to there list of offerings?

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Dr. Geoff Lomax: You raise a number of questions and point here; they are all very good and it’s is hard to give a comprehensive response to each one, but here is my reaction:

  • There are many practitioners in the field of orthopedics who sincerely believe in the potential of cell-based treatments to treat injury / pain
  • Most of the evidence presented is case reports that individuals have benefited
  • The challenge we face is not know the exact type of injury and cell treatments used.
  • Well controlled clinical trials would really help us understand for what cells (or cell products) and for what injury would be helpful
  • Prices of $3000 to $5000 are not uncommon, and like other forms of private medicine there is often a considerable mark-up in relation to cost of goods.
  • You are correct that there have not been reports of serious injury for knee injections
  • However the effectiveness is not clear while simultaneously millions of people have been aided by knee replacements.

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Do stem cells have benefits for patients going through chemotherapy and radiation therapy? Ruperto

Dr. Kelly Shepard: The idea that a stem cell therapy could help address effects of chemotherapy or radiation is being and has been pursued by several investigators over the years, including some with CIRM support. Towards the earlier stages, people are looking at the ability of different stem cell-derived neural cell preparations to replace or restore function of certain brain cells that are damaged by the effects of chemotherapy or radiation. In a completely different type of approach, a group at City of Hope is exploring whether a bone marrow transplant with specially modified stem cells can provide a protective effect against the chemotherapy that is used to treat a form of brain cancer, glioblastoma. This study is in the final stage of development that, if all goes well, culminates with application to the FDA to allow initiation of a clinical trial to test in people.

Dr. Ingrid Caras: That’s an interesting and valid question.  There is a Phase 1 trial ongoing that is evaluating a novel type of stem/progenitor cell from the umbilical cord of healthy deliveries.  In animal studies, these cells have been shown to reduce the toxic effects of chemotherapy and radiation and to speed up recovery. These cells are now being tested in a First-in-human clinical trial in patients who are undergoing high-dose chemotherapy to treat their disease.

There is a researcher at Stanford, Michelle Monje, who is investigating that the role of damage to stem cells in the cognitive problems that sometimes arise after chemo- and radiation therapy (“chemobrain”).  It appears that damage to stem cells in the brain, especially those responsible for producing oligodendrocytes, contributes to chemobrain.  In CIRM-funded work, Dr. Monje has identified small molecules that may help prevent or ameliorate the symptoms of chemobrain.

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Is it possible to use a technique developed to fight one disease to also fight another? For instance, the bubble baby disease, which has cured (I think) more than 50 children, may also help fight sickle cell anemia?  Don Reed.

Dr. Lisa Kadyk: Hi Don. Yes, the same general technique can often be applied to more than one disease, although it needs to be “customized” for each disease.   In the example you cite, the technique is an “autologous gene-modified bone marrow transplant” – meaning the cells come from the patient themselves.  This technique is relevant for single gene mutations that cause diseases of the blood (hematopoietic) system.  For example, in the case of “bubble baby” diseases, a single mutation can cause failure of immune cell development, leaving the child unable to fight infections, hence the need to have them live in a sterile “bubble”.   To cure that disease, blood stem cells, which normally reside in the bone marrow, are collected from the patient and then a normal version of the defective gene is introduced into the cells, where it is incorporated into the chromosomes.   Then, the corrected stem cells are transplanted back into the patient’s body, where they can repopulate the blood system with cells expressing the normal copy of the gene, thus curing the disease.  

A similar approach could be used to treat sickle cell disease, since it is also caused by a single gene mutation in a gene (beta hemoglobin) that is expressed in blood cells.  The same technique would be used as I described for bubble baby disease but would differ in the gene that is introduced into the patient’s blood stem cells. 

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Is there any concern that CIRM’s lack of support in basic research will hamper the amount of new approaches that can reach clinical stages? Jason

Dr. Kelly Shepard: CIRM always has and continues to believe that basic research is vital to the field of regenerative medicine. Over the past 10 years CIRM has invested $904 million in “discovery stage/basic research”, and about $215 million in training grants that supported graduate students, post docs, clinical fellows, undergraduate, masters and high school students performing basic stem cell research. In the past couple of years, with only a limited amount of funds remaining, CIRM made a decision to invest most of the remaining funds into later stage projects, to support them through the difficult transition from bench to bedside. However, even now, CIRM continues to sponsor some basic research through its Bridges and SPARK Training Grant programs, where undergraduate, masters and even high school students are conducting stem cell research in world class stem cell laboratories, many of which are the same laboratories that were supported through CIRM basic research grants over the past 10 years. While basic stem cell research continues to receive a substantial level of support from the NIH ($1.8 billion in 2018, comprehensively on stem cell projects) and other funders, CIRM believes continued support for basic research, especially in key areas of stem cell research and vital opportunities, will always be important for discovering and developing new treatments.

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What is the future of the use of crispr cas9 in clinical trials in california/globally. Art Venegas

Dr. Kelly Shepard: CRISPR/Cas9 is a powerful gene editing tool. In only a few years, CRISPR/Cas9 technology has taken the field by storm and there are already a few CRISPR/Cas9 based treatments being tested in clinical trials in the US. There are also several new treatments that are at the IND enabling stage of development, which is the final testing stage required by the FDA before a clinical trial can begin. Most of these clinical trials involving CRISPR go through an “ex vivo” approach, taking cells from the patient with a disease causing gene, correcting the gene in the laboratory using CRISPR, and reintroducing the cells carrying the corrected gene back into the patient for treatment.  Sickle cell disease is a prime example of a therapy being developed using this strategy and CIRM funds two projects that are preparing for clinical trials with this approach.  CRISPR is also being used to develop the next generation of cancer T-cell therapies (e.g. CAR-T), where T-cells – a vital part of our immune system – are modified to target and destroy cancer cell populations.  Using CRISPR to edit cells directly in patients “in vivo” (inside the body) is far less common currently but is also being developed.  It is important to note that any FDA sanctioned “in vivo” CRISPR clinical trial in people will only modify organ-specific cells where the benefits cannot be passed on to subsequent generations. There is a ban on funding for what are called germ line cells, where any changes could be passed down to future generations.

CIRM is currently supporting multiple CRISPR/Cas9 gene editing projects in California from the discovery or most basic stage of research, through the later stages before applying to test the technique in people in a clinical trial.

While the field is new – if early safety signals from the pioneering trials are good, we might expect a number of new CRISPR-based approaches to enter clinical testing over the next few years. The first of these will will likely be in the areas of bone marrow transplant to correct certain blood/immune or  metabolic diseases, and cancer immunotherapies, as these types of approaches are the best studied and furthest along in the pipeline.

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Explain the differences between gene therapy and stem cell therapy? Renee Konkol

Dr. Stephen Lin:  Gene therapy is the direct modification of cells in a patient to treat a disease.  Most gene therapies use modified, harmless viruses to deliver the gene into the patient.  Gene therapy has recently seen many success in the clinic, with the first FDA approved therapy for a gene induced form of blindness in 2017 and other approvals for genetic forms of smooth muscle atrophy and amyloidosis. 

Stem cell therapy is the introduction of stem cells into patients to treat a disease, usually with the purpose of replacing damaged or defective cells that contribute to the disease.  Stem cell therapies can be derived from pluripotent cells that have the potential to turn into any cell in the body and are directed towards a specific organ lineage for the therapy.  Stem cell therapies can also be derived from other cells, called progenitors, that have the ability to turn into a limited number of other cells in the body. for example hematopoietic or blood stem cells (HSCs), which are found in bone marrow, can turn into other cells of the blood system including B-cells and T-cells: while mesenchymal stem cells (MSCs), which are usually found in fat tissue, can turn into bone, cartilage, and fat cells.  The source of these cells can be from the patient’s own body (autologous) or from another person (allogeneic).

Gene therapy is often used in combination with cell therapies when cells are taken from the patient and, in the lab, modified genetically to correct the mutation or to insert a correct form of the defective gene, before being returned to patients.  Often referred to as “ex vivo gene therapy” – because the changes are made outside the patient’s body – these therapies include Chimeric Antigen Receptor T (CAR-T) cells for cancer therapy and gene modified HSCs to treat blood disorders such as severe combined immunodeficiency and sickle cell disease. This is an exciting area that has significantly improved and even cured many people already.

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Currently, how can the outcome of CIRM stem cell medicine projects and clinical trials be soundly interpreted when their stem cell-specific doses are not known? James L. Sherley, M.D., Ph.D., Director. Asymmetrex, LLC

Dr. Stephen Lin:  Stem cell therapies that receive approval to conduct clinical trials must submit a package of data to the FDA that includes studies that demonstrate their effectiveness, usually in animal models of the disease that the cell therapy is targeting.  Those studies have data on the dose of the cell therapy that creates the therapeutic effect, which is used to estimate cell doses for the clinical trial.  CIRM funds discovery and translational stage awards to conduct these types of studies to prepare cell therapies for clinical trials.  The clinical trial is also often designed to test multiple doses of the cell therapy to determine the one that has the best therapeutic effect.   Dosing can be very challenging with cell therapies because of issues including survival, engraftment, and immune rejection, but CIRM supports studies designed to provide data to give the best estimate possible.

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Is there any research on using stem cells to increase the length of long bones in people?” For example, injecting stem cells into the growth plates to see if the cells can be used to lengthen limbs. Sajid

Dr. Kelly Shepard: There is quite a lot of ongoing research seeking ways to repair bones with stem cell based approaches, which is not the same but somewhat related. Much of this is geared towards repairing the types of bone injuries that do not heal well naturally on their own (large gaps, dead bone lesions, degenerative bone conditions). Also, a lot of this research involves engineering bone tissues in the lab and introducing the engineered tissue into a bone lesion that need be repaired. What occurs naturally at the growth plate is a complex interaction between many different cell types, much of which we do not fully understand. We do not fully understand how to use the cells that are used to engineer bone tissue in the lab. However, a group at Stanford, with some CIRM support, recently discovered a “skeletal stem cell” that exists naturally at the ends of human bones and at sites of fracture.  These are quite different than MSCs and offer a new path to be explored for repairing and generating bone. 

CIRM Board Awards $15.8 Million to Four Translational Research Projects

Last week, the CIRM Board approved $32.92 million in awards directed towards four new clinical trials in vision related diseases and Parkinson’s Disease.

In addition to these awards, the Board also approved investing $15.80 million in four awards in the 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 we go into more specific details of each one of these awards, here is a table summarizing these four new projects:

ApplicationTitleInstitutionAward Amount
TRAN1 11536Ex Vivo Gene Editing of Human Hematopoietic Stem Cells for the Treatment of X-Linked Hyper IgM Syndrome  UCLA $4,896,628
TRAN1 11555BCMA/CS1 Bispecific CAR-T Cell Therapy to Prevent Antigen Escape in Multiple Myeloma  UCLA $3,176,805
TRAN1 11544 Neural Stem cell-mediated oncolytic immunotherapy for ovarian cancer  City of Hope $2,873,262
TRAN1 11611Development of a human stem cell-derived inhibitory neuron therapeutic for the treatment of chronic focal epilepsyNeurona Therapeutics$4,848,750
Dr. Caroline Kuo, UCLA

$4.89 million was awarded to Dr. Caroline Kuo at UCLA to pursue a gene therapy approach for X-Linked Hyper IgM Syndrome (X-HIM).

X-HIM is a hereditary immune disorder observed predominantly in males in which there are abnormal levels of different types of antibodies in the body.  Antibodies are also known as Immunoglobulin (Ig) and they combat infections by attaching to germs and other foreign substances, marking them for destruction.  In infants with X-HIM, there are normal or high levels of antibody IgM but low levels of antibodies IgG, IgA, and IgE.  The low level of these antibodies make it difficult to fight off infection, resulting in frequent pneumonia, sinus infections, ear infections, and parasitic infections.  Additionally, these infants have an increased risk of cancerous growths. 

The gene therapy approach Dr. Kuo is continuing to develop involves using CRISPR/Cas9 technology to modify human blood stem cells with a functional version of the gene necessary for normal levels of antibody production.  The ultimate goal would be to take a patient’s own blood stem cells, modify them with the corrected gene, and reintroduce them back into the patient.

CIRM has previously funded Dr. Kuo’s earlier work related to developing this gene therapy approach for XHIM.

Dr. Yvonne Chen, UCLA

$3.17 million was awarded to Dr. Yvonne Chen at UCLA to develop a CAR-T cell therapy for multiple myeloma (MM).

MM is a type of blood cancer that forms in the plasma cell, a type of white blood cell that is found in the bone marrow.  An estimated 32,110 people in the United States will be diagnosed with MM in 2019 alone.  Several treatment options are available to patients with MM, but there is no curative therapy.

The therapy that Dr. Chen is developing will consist of a genetically-modified version of the patient’s own T cells, which are an immune system cell that can destroy foreign or abnormal cells.  The T cells will be modified with a protein called a chimeric antigen receptor (CAR) that will recognize BCMA and CS1, two different markers found on the surface of MM cells.  These modified T cells (CAR-T cells) are then infused into the patient, where they are expected to detect and destroy BCMA and CS1 expressing MM cells.

Dr. Chen is using CAR-T cells that can detect two different markers in a separate clinical trial that you can read about in a previous blog post.

Dr. Karen Aboody, City of Hope

$2.87 million was awarded to Dr. Karen Aboody at City of Hope to develop an immunotherapy delivered via neural stem cells (NSCs) for treatment of ovarian cancer.

Ovarian cancer affects approximately 22,000 women per year in the United States alone.  Most ovarian cancer patients eventually develop resistance to chemotherapy, leading to cancer progression and death, highlighting the need for treatment of recurring ovarian cancer.

The therapy that Dr. Aboody is developing will use an established line of NSCs to deliver a virus that specifically targets these tumor cells.  Once the virus has entered the tumor cell, it will continuously replicate until the cell is destroyed.  The additional copies of the virus will then go on to target neighboring tumor cells.  This process could potentially stimulate the body’s own immune response to fight off the cancer cells as well.

Dr. Cory Nicholas, Neurona Therapeutics

$4.85 million was awarded to Dr. Cory Nicholas at Neurona Therapeutics to develop a treatment for epilepsy.

Epilepsy affects more than 3 million people in the United States with about 150,000 newly diagnosed cases in the US every year. It results in persistent, difficult to manage, or uncontrollable seizures that can be disabling and significantly impair quality of life. Unfortunately, anti-epileptic drugs fail to manage the disease in a large portion of people with epilepsy. Approximately one-third of epilepsy patients are considered to be drug-resistant, meaning that they do not adequately respond to at least two anti-epileptic drugs.

The therapy that Dr. Nicholas is developing will derive interneurons from human embryonic stem cells (hESCs). These newly derived interneurons would then be delivered to the brain via injection whereby the new cells are able to help regulate aberrant brain activity and potentially eliminate or significantly reduce the occurrence of seizures.

CIRM has previously funded the early stage development of this approach via a comprehensive grant and discovery grant.