At CIRM we are modest enough to know that we can’t do everything by ourselves. To succeed we need partners. And in UC Davis we have a terrific partner. The work they do in advancing stem cell research is exciting and really promising. But it’s not just the science that makes them so special. It’s also their compassion and commitment to caring for patients.
What follows is an excerpt from an article by Lisa Howard on the work they do at UC Davis. When you read it you’ll see why we are honored to be a part of this research.
Gene therapy research at UC Davis
UC Davis’ commitment to stem cell and gene therapy research dates back more than a decade.
In 2010, with major support from the California Institute for Regenerative Medicine (CIRM), UC Davis launched the UC Davis Institute for Regenerative Cures, which includes research facilities as well as a Good Manufacturing Practice (GMP) facility.
Led by Jan Nolta, a professor of cell biology and human anatomy and the director of the UC Davis Institute for Regenerative Cures, the new center leverages UC Davis’ network of expert researchers, facilities and equipment to establish a center of excellence aimed at developing lifelong cures for diseases.
Nolta began her career at the University of Southern California working with Donald B. Kohn on a cure for bubble baby disease, a condition in which babies are born without an immune system. The blood stem cell gene therapy has cured more than 50 babies to date.
Work at the UC Davis Gene Therapy Center targets disorders that potentially can be treated through gene replacement, editing or augmentation.
“The sectors that make up the core of our center stretch out across campus,” said Nolta. “We work with the MIND Institute a lot. We work with the bioengineering and genetics departments, and with the Cancer Center and the Center for Precision Medicine and Data Sciences.”
A recent UC Davis stem cell study shows a potential breakthrough for healing diabetic foot ulcers with a bioengineered scaffold made up of human mesenchymal stem cells (MSCs). Another recent study revealed that blocking an enzyme linked with inflammation enables stem cells to repair damaged heart tissue. A cell gene therapy study demonstrated restored enzyme activity in Tay-Sachs disease affected cells in humanized mouse models.
“Some promising and exciting research right now at the Gene Therapy Center comes from work with hematopoietic stem cells and with viral vector delivery,” said Nolta.
Hematopoietic stem cells give rise to other blood cells. A multi-institutional Phase I clinical trial using hematopoietic stem cells to treat HIV-lymphoma patients is currently underway at UC Davis.
“We are genetically engineering a patient’s own blood stem cells with genes that block HIV infection,” said Joseph Anderson, an associate professor in the UC Davis Department of Internal Medicine. The clinical trial is a collaboration with Mehrdad Abedi, the lead principal investigator.
“When the patients receive the modified stem cells, any new immune system cell, like T-cell or macrophage, that is derived from one of these stem cells, will contain the HIV-resistant genes and block further infection,” said Anderson.
He explained that an added benefit with the unique therapy is that it contains an additional gene that “tags” the stem cells. “We are able to purify the HIV-resistant cells prior to transplantation, thus enriching for a more protective cell population.
Kyle David Fink
Kyle David Fink, an assistant professor of neurology at UC Davis, is affiliated with the Stem Cell Program and Institute for Regenerative Cures. His lab is focused on leveraging institutional expertise to bring curative therapies to rare, genetically linked neurological disorders.
“We are developing novel therapeutics targeted to the underlying genetic condition for diseases such as CDKL5 deficiency disorder, Angelman, Jordan and Rett syndromes, and Juvenile Huntington’s disease,” said Fink.
The lab is developing therapies to target the underlying genetic condition using DNA-binding domains to modify gene expression in therapeutically relevant ways. They are also creating novel delivery platforms to allow these therapeutics to reach their intended target: the brain.
“The hope is that these highly innovative methods will speed up the progress of bringing therapies to these rare neurodegenerative disease communities,” said Fink.
Jasmine Carter, a graduate research assistant at the UC Davis Stem Cell Program, October 18, 2019. (AJ Cheline/UC Davis)
Developing potential lifetime cures
Among Nolta’s concerns is how expensive gene therapy treatments can be.
“Some of the therapies cost half a million dollars and that’s simply not available to everyone. If you are someone with no insurance or someone on Medicare, which reimburses about 65 percent, it’s harder for you to get these life-saving therapies,” said Nolta.
To help address that for cancer patients at UC Davis, Nolta has set up a team known as the “CAR T Team.”
Chimeric antigen receptor (CAR) T-cell therapy is a type of immunotherapy in which a patient’s own immune cells are reprogrammed to attack a specific protein found in cancer cells.
“We can develop our own homegrown CAR T-cells,” said Nolta. “We can use our own good manufacturing facility to genetically engineer treatments specifically for our UC Davis patients.”
Although safely developing stem cell treatments can be painfully slow for patients and their families hoping for cures, Nolta sees progress every day. She envisions a time when gene therapy treatments are no longer considered experimental and doctors will simply be able to prescribe them to their patients.
“And the beauty of the therapy is that it can work for the lifetime of a patient,” said Nolta.
COVID-19 and social and racial injustice are two of the biggest challenges facing the US right now. This Thursday, October 8th, we are holding a conversation that explores finding answers to both.
The CIRM Alpha Stem Cell Clinic Network Symposium is going to feature presentations about advances in stem cell and regenerative research, highlighting treatments that are already in the clinic and being offered to patients.
But we’re also going to dive a little deeper into the work we support, and use it to discuss two of the most pressing issues of the day.
One of the topics being featured is research into COVID-19. To date CIRM has funded 17 different projects, including three clinical trials. We’ll talk about how these are trying to find ways to help people infected with the virus, seeing if stem cells can help restore function to organs and tissues damaged by the virus, and if we can use stem cells to help develop safe and effective vaccines.
Immediately after that we are going to use COVID-19 as a way of exploring how the people most at risk of being infected and suffering serious consequences, are also the ones most likely to be left out of the research and have most trouble accessing treatments and vaccines.
Study after study highlights how racial and ethnic minorities are underrepresented in clinical trials and disproportionately affected by debilitating diseases. We have a responsibility to change that, to ensure that the underserved are given the same opportunity to take part in clinical trials as other communities.
How do we do that, how do we change a system that has resisted change for so long, how do we overcome the mistrust that has built up in underserved communities following decades of abuse? We’ll be talking about with experts who are on the front lines of this movement.
It promises to be a lively meeting. We’d love to see you there. It’s virtual – of course – it’s open to everyone, and it’s free.
Whenever you are designing something new you always have to keep in mind who the end user is. You can make something that works perfectly fine for you, but if it doesn’t work for the end user, the people who are going to work with it day in and day out, you have been wasting your time. And their time too.
At CIRM our end users are the patients. Everything we do is about them. Starting with our mission statement: to accelerate stem cell treatments to patients with unmet medical needs. Everything we do, every decision we make, has to keep the needs of the patient in mind.
So, when we were planning our recent 2020 Grantee Meeting (with our great friends and co-hosts UC Irvine and UC San Diego) one of the things we wanted to make sure didn’t get lost in the mix was the face and the voice of the patients. Often big conferences like this are heavy on science with presentations from some of the leading researchers in the field. And we obviously wanted to make sure we had that element at the Grantee meeting. But we also wanted to make sure that the patient experience was front and center.
And we did just that. But more on that in a minute. First, let’s talk about why the voice of the patient is important.
Some years ago, Dr. David Higgins, a CIRM Board member and patient advocate for Parkinson’s Disease (PD), said that when researchers are talking about finding treatments for PD they often focus on the dyskinesia, the trembling and shaking and muscle problems. However, he said if you actually asked people with PD you’d find they were more concerned with other aspects of the disease, the insomnia, anxiety and depression among other things. The key is you have to ask.
So, we asked some of our patient advocates if they would be willing to be part of the Grantee Meeting. All of them, without hesitation, said yes. They included Frances Saldana, a mother who lost three of her children to Huntington’s disease; Kristin MacDonald, who lost her sight to a rare disorder but regained some vision thanks to a stem cell therapy and is hoping the same therapy will help restore some more; Pawash Priyank, whose son Ronnie was born with a fatal immune disorder but who, thanks to a stem cell/gene therapy treatment, is now healthy and leading a normal life.
Because of the pandemic everything was virtual, but it was no less compelling for that. We interviewed each of the patients or patient advocates beforehand and those videos kicked off each session. Hearing, and seeing, the patients and patient advocates tell their stories set the scene for what followed. It meant that the research the scientists talked about took on added significance. We now had faces and names to highlight the importance of the work the scientists were doing. We had human stories. And that gave a sense of urgency to the work the researchers were doing.
But that wasn’t all. After all the video presentations each session ended with a “live” panel discussion. And again, the patients and patient advocates were a key part of that. Because when scientists talk about taking their work into a clinical trial they need to know if the way they are setting up the trial is going to work for the patients they’re hoping to recruit. You can have the best scientists, the most promising therapy, but if you don’t design a clinical trial in a way that makes it easy for patients to be part of it you won’t be able to recruit or retain the people you need to test the therapy.
Patient voices count. Patient stories count.
But more than anything, hearing and seeing the people we are trying to help reminds us why we do this work. It’s so easy to get caught up in the day to day business of our jobs, struggling to get an experiment to work, racing to get a grant application in before the deadline. Sometimes we get so caught up in the minutiae of work we lose sight of why we are doing it. Or who we are doing it for.
At CIRM we have a saying; come to work every day as if lives depend on you, because lives depend on you. Listening to the voices of patients, seeing their faces, hearing their stories, reminds us not to waste a moment. Because lives depend on all of us.
Here’s one of the interviews that was featured at the event. I do apologize in advance for the interviewer, he’s rubbish at his job.
One of our favorite things to do at CIRM is deliver exciting news about CIRM projects. This usually entails discussion of recent discoveries that made headlines, or announcing the launch of a new CIRM-funded clinical trial …. tangible signs of progress towards addressing unmet medical needs through advances in stem technology.
But there are equally exciting signs of progress that are not always so obvious to the untrained eye- those that we are privileged to witness behind the scenes at CIRM. These efforts don’t always lead to a splashy news article or even to a scientific publication, but they nonetheless drive the evolution of new ideas and can help steer the field away from futile lines of investigation. Dozens of such projects are navigating uncharted waters by filling knowledge gaps, breaking down technical barriers, and working closely with regulatory agencies to define novel and safe paths to the clinic.
These efforts can remain “hidden” because they are in the intermediate stages of the long, arduous and expensive journey from “bench to beside”. For the pioneering projects that CIRM funds, this journey is unique and untrod, and can be fraught with false starts. But CIRM has developed tools to track the momentum of these programs and provide continuous support for those with the most promise. In so doing, we have watched projects evolve as they wend their way to the clinic. We wanted to share a few examples of how we do this with our readers, but first… a little background for our friends who are unfamiliar with the nuts and bolts of inventing new medicines.
A common metaphor for bringing scientific discoveries to market is a pipeline, which begins in a laboratory where a discovery occurs, and ends with government approval to commercialize a new medicine, after it is proven to be safe and effective. In between discovery and approval is a stage called “Translation”, where investigators develop ways to transition their “research level” processes to “clinically compatible” ones, which only utilize substances that are of certified quality for human use.
Investigators must also work out novel ways to manufacture the product at larger scale and transition the methods used for testing in animal models to those that can be implemented in human subjects.
A key milestone in Translation is the “preIND” (pre Investigational New Drug (IND) meeting, where an investigator presents data and plans to the US Food and Drug Administration (FDA) for feedback before next stage of development begins, the pivotal testing needed to show it is both safe and effective.
These “IND enabling studies” are rigorous but necessary to support an application for an IND and the initiation of clinical trials, beginning with phase 1 to assess safety in a small number of individuals, and phase 2, where an expanded group is evaluated to see if the therapy has any benefits for the patient. Phase 3 trials are studies of very large numbers of individuals to gain definitive evidence of safety and therapeutic effect, generally the last step before applying to the FDA for market approval. An image of the pipeline and the stages described are provided in our diagram below.
The pipeline can be notoriously long and tricky, with plenty of twists, turns, and unexpected obstacles along the way. Many more projects enter than emerge from this gauntlet, but as we see from these examples of ‘works in progress”, there is a lot of momentum building.
Caption for Graphic:This graphic shows the number of CIRM-funded projects and the stages they have progressed through multiple rounds of CIRM funding. For example, the topmost arrow shows that are about 19 projects at the translational stage of the pipeline that received earlier support through one of CIRM’s Discovery stage programs. Many of these efforts came out of our pre-2016 funding initiatives such as Early Translation, Basic Biology and New Faculty Awards. In another example, you can see that about 15 awards that were first funded by CIRM at the IND enabling stage have since progressed into a phase 1 or phase 2 clinical trials. While most of these efforts also originated in some of CIRM’s pre-2016 initiatives such as the Disease Team Awards, others have already progressed from CIRM’s newer programs that were launched as part of the “2.0” overhaul in 2016 (CLIN1).
The number of CIRM projects that have evolved and made their way down the pipeline with CIRM support is impressive, but it is clearly an under-representation, as there are other projects that have progressed outside of CIRM’s purview, which can make things trickier to verify.
We also track projects that have spun off or been licensed to commercial organizations, another very exciting form of “progression”. Perhaps those will contribute to another blog for another day! In the meantime, here are a just a few examples of some of the progressors that are depicted on the graphic.
Project: stem cell therapy to enhance bone healing in theelderly
– Currently funded stage: IND enabling development, CLIN1-11256 (Dr. Zhu, Ankasa Regenerative Therapeutics)
Every so often you hear a story and your first reaction is “oh, I have to share this with someone, anyone, everyone.” That’s what happened to me the other day.
I was talking with Kristin MacDonald, an amazing woman, a fierce patient advocate and someone who took part in a CIRM-funded clinical trial to treat retinitis pigmentosa (RP). The disease had destroyed Kristin’s vision and she was hoping the therapy, pioneered by jCyte, would help her. Kristin, being a bit of a pioneer herself, was the first person to test the therapy in the U.S.
Anyway, Kristin was doing a Zoom presentation and wanted to look her best so she asked a friend to come over and do her hair and makeup. The woman she asked, was Rosie Barrero, another patient in that RP clinical trial. Not so very long ago Rosie was legally blind. Now, here she was helping do her friend’s hair and makeup. And doing it beautifully too.
That’s when you know the treatment works. At least for Rosie.
There are many other stories to be heard – from patients and patient advocates, from researchers who develop therapies to the doctors who deliver them. – at our CIRM 2020 Grantee Meeting on next Monday September 14th Tuesday & September 15th.
It’s two full days of presentations and discussions on everything from heart disease and cancer, to COVID-19, Alzheimer’s, Parkinson’s and spina bifida. Here’s a link to the Eventbrite page where you can find out more about the event and also register to be part of it.
Like pretty much everything these days it’s a virtual event so you’ll be able to join in from the comfort of your kitchen, living room, even the backyard.
And it’s free!
You can join us for all two days or just one session on one day. The choice is yours. And feel free to tell your friends or anyone else you think might be interested.
It’s not often you get a chance to hear some of the brightest minds around talk about their stem cell research and what it could mean for you, me and everyone else. That’s why we’re delighted to be bringing some of the sharpest tools in the stem cell shed together in one – virtual – place for our CIRM 2020 Grantee Meeting.
The event is Monday September 14th and Tuesday September 15th. It’s open to anyone who wants to attend and, of course, it’s all being held online so you can watch from the comfort of your own living room, or garden, or wherever you like. And, of course, it’s free.
Dr. Daniela Bota, UC Irvine
The list of speakers is a Who’s Who of researchers that CIRM has funded and who also happen to be among the leaders in the field. Not surprising as California is a global center for regenerative medicine. And you will of course be able to post questions for them to answer.
Dr. Deepak Srivastava, Gladstone Institutes
The key speakers include:
Larry Goldstein: the founder and director of the UCSD Stem Cell Program talking about Alzheimer’s research
Irv Weissman: Stanford University talking about anti-cancer therapies
Other topics include the latest stem cell approaches to COVID-19, spinal cord injury, blindness, Parkinson’s disease, immune disorders, spina bifida and other pediatric disorders.
You can choose one topic or come both days for all the sessions. To see the agenda for each day click here. Just one side note, this is still a work in progress so some of the sessions have not been finalized yet.
And when you are ready to register go to our Eventbrite page. It’s simple, it’s fast and it will guarantee you’ll be able to be part of this event.
It’s been a long time coming. Eighteen months to be precise. Which is a peculiarly long time for an Annual Report. The world is certainly a very different place today than when we started, and yet our core mission hasn’t changed at all, except to spring into action to make our own contribution to fighting the coronavirus.
This latest CIRM Annual Reportcovers 2019 through June 30, 2020. Why? Well, as you probably know we are running out of money and could be funding our last new awards by the end of this year. So, we wanted to produce as complete a picture of our achievements as we could – keeping in mind that we might not be around to produce a report next year.
It’s a pretty jam-packed report. It covers everything from the 14 new clinical trials we have funded this year, including three specifically focused on COVID-19. It looks at the extraordinary researchers that we fund and the progress they have made, and the billions of additional dollars our funding has helped leverage for California. But at the heart of it, and at the heart of everything we do, are the patients. They’re the reason we are here. They are the reason we do what we do.
There are stories of people like Byron Jenkins who almost died from multiple myeloma but is now back leading a full, active life with his family thanks to a CIRM-funded therapy with Poseida. There is Jordan Janz, a young man who once depended on taking 56 pills a day to keep his rare disease, cystinosis, under control but is now hoping a stem cell therapy developed by Dr. Stephanie Cherqui and her team at UC San Diego will make that something of the past.
These individuals are remarkable on so many levels, not the least because they were willing to be among the first people ever to try these therapies. They are pioneers in every sense of the word.
There is a lot of information in the report, charting the work we have done over the last 18 months. But it’s also a celebration of everyone who made it possible, and our way of saying thank you to the people of California who gave us this incredible honor and opportunity to do this work.
Frances Saldana is one of the most remarkable women I know. She has lost all three of her children to Huntington’s disease (HD) – a nasty, fatal disease that steadily destroys the nerve cells in the brain – but still retains a fighting spirit and a commitment to finding a cure for HD. She is the President Emeritus for HD-Care, an organization dedicated to raising awareness about HD, and finding money for research to cure it. She recently wrote a Mother’s Day blog for HD-Care about the similarities between HD and COVID-19. As May is National Huntington’s Disease Awareness Month we wanted to share her blog with you.
COVID-19 has consumed our entire lives, and for many, our livelihoods. This is a pandemic like we have never experienced in our lifetime, bringing out in many families fear, financial devastation, disabilities, isolation, suffering, and worst of all, loss of life. But through all this, the pandemic has uncovered emotions in many who rose to the occasion – a fight and stamina beyond human belief.
As a family member who has lost all of my children to Huntington’s disease, it makes me so sad to watch and hear about the suffering that people all over the world are currently experiencing with COVID-19. This devastation is nothing new to Huntington’s disease families. Although Huntington’s disease (HD) is not contagious, it is genetic, and much of the uncertainty and fears that families are experiencing are so similar to what HD families experience….in slow motion, with unanswered questions such as:
Who in my family is carrying the mutant HD gene? (Who in my family is carrying the coronavirus?)
Who in my family will inherit the mutant HD gene? (Who will get infected by the COVID-19?)
Will my loved on live long enough to benefit from a treatment for HD? (Will there be a vaccination soon if my loved one is infected by COVID-19?)
How long will my HD family member live? (Will my affected COVID-19 loved one survive after being placed on a ventilator?)
Is my HD family member going to die? (Will my COVID-19 family member die?)
In watching some of the footage of COVID-19 patients on TV and learning about the symptoms, it appears that those with a severe case of the virus go through similar symptoms as HD patients who are in the late and end-of-life stages: pneumonia, sepsis, pain, and suffering, to name a few, although for HD families, the journey goes on for years or even decades, and then carries on to the next generation, and not one HD patient will survive the disease. Not yet!
Scientists are working furiously all over the world to find a treatment for COVID-19. The same goes for scientists focused on Huntington’s disease research. Without their brilliant work we would have no hope. Without funding there would be no science. I have been saying for the last 20 years that we will have a treatment for Huntington’s disease in the next couple of years, but with actual facts and successful clinical trials, there is finally a light at the end of the tunnel and we have much to be thankful for. I feel it in my heart that a treatment will be found for both COVID-19 and Huntington’s disease very soon.
The month of May happens to be National Huntington’s Disease Awareness Month. Mother’s Day also falls in the month of May. Huntington’s disease “Warrior Moms” are exemplary women, and I have been blessed to have known a few. Driven by love for their children, they’ve worn many hats as caregivers, volunteers, and HD community leaders in organizations such as HD-CARE, HDSA, WeHaveAFace, Help4HD, HD Support &Care Network, and many others.
The mothers have often also been forced to take on the role of breadwinners when the father of the family has unexpectedly become debilitated from HD. In spite of carrying a heavy cross, HD Warrior Moms persevere, and they do it with endless love, often taking care of HD family members from one generation to the next. They are the front-line workers in the HD community, tirelessly protecting their families and at the same time doing all they can to provide a meaningful quality of life.
Many HD Warrior moms have lost their children in spite of their fierce fight to save them, but they keep their memory alive, never losing hope for a treatment that will end the pain, suffering, and loss of life. Many HD Warrior Moms have lost the fight themselves, not from HD, but from a broken heart. These are the HD Warrior Moms.
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.
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.
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.
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.
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.
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: 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.
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: 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.
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.
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.
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:
Visual loss from damage to the retina
You could have a normal eye with damage to the area of the brain that controls the eye’s movement
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.
Is there any stem cell therapy for optical nerve damage? Deanna Rice
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
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.
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.
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.
What advances have been made using stem cells for the treatment of Type 2 Diabetes?Mary Rizzo
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.
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.
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.
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.
What is happening with Parkinson’s research? Hanifa Gaphoor
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.
Any plans for Huntington’s?Nikhat Kuchiki
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)
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?
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.
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: 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.
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: 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.
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?
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.
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.
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.
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.
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.
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.
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.
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.