Funding a Clinical Trial for a Functional Cure for HIV

The use of antiretroviral drugs has turned HIV/AIDS from a fatal disease to one that can, in many cases in the US, be controlled. But these drugs are not a cure. That’s why the governing Board of the California Institute for Regenerative Medicine (CIRM) voted to approve investing $6.85 million in a therapy that aims to cure the disease.

This is the 82nd clinical trial funded by CIRM.

There are approximately 38 million people worldwide living with HIV/AIDS. And each year there are an estimated 1.5 million new cases. The vast majority of those living with HIV do not have access to the life-saving antiretroviral medications that can keep the virus under control. People who do have access to the medications face long-term complications from them including heart disease, bone, liver and kidney problems, and changes in metabolism.

The antiretroviral medications are effective at reducing the viral load in people with HIV, but they don’t eliminate it. That’s because the virus that causes AIDS can integrate its DNA into long-living cells in the body and remain dormant. When people stop taking their medications the virus is able to rekindle and spread throughout the body.

Dr. William Kennedy and the team at Excision Bio Therapeutics have developed a therapeutic candidate called EBT-101. This is the first clinical study using the CRISPR-based platform for genome editing and excision of the latent form of HIV-1, the most common form of the virus that causes AIDS in the US and Europe. The goal is to eliminate or sufficiently reduce the hidden reservoirs of virus in the body to the point where the individual is effectively cured.

“To date only a handful of people have been cured of HIV/AIDS, so this proposal of using gene editing to eliminate the virus could be transformative,” says Dr. Maria Millan, President and CEO of CIRM. “In California alone there are almost 140,000 people living with HIV. HIV infection continues to disproportionately impact marginalized populations, many of whom are unable to access the medications that keep the virus under control. A functional cure for HIV would have an enormous impact on these communities, and others around the world.”

In a news release announcing they had dosed the first patient, Daniel Dornbusch, CEO of Excision, called it a landmark moment. “It is the first time a CRISPR-based therapy targeting an infectious disease has been administered to a patient and is expected to enable the first ever clinical assessment of a multiplexed, in vivo gene editing approach. We were able to reach this watershed moment thanks to years of innovative work by leading scientists and physicians, to whom we are immensely grateful. With this achievement, Excision has taken a major step forward in developing a one-time treatment that could transform the HIV pandemic by freeing affected people from life-long disease management and the stigma of disease.”

The Excision Bio Therapeutics team also scored high on their plan for Diversity, Equity and Inclusion. Reviewers praised them for adding on a partnering organization to provide commitments to serve underserved populations, and to engaging a community advisory board to help guide their patient recruitment.

CIRM has already invested almost $81 million in 20 projects targeting HIV/AIDS, including four clinical trials.

A better, faster, more effective way to edit genes

Clinical fellow Brian Shy talks with postdoctoral scholar Tori Yamamoto in the Marson Lab at Gladstone Institutes on June 8th, 2022. Photo courtesy Gladstone Institutes.

For years scientists have been touting the potential of CRISPR, a gene editing tool that allows you to target a specific mutation and either cut it out or replace it with the corrected form of the gene. But like all new tools it had its limitations. One important one was the difficult in delivering the corrected gene to mature cells in large numbers.

Scientists at the Gladstone Institutes and U.C. San Francisco say they think they have found a way around that. And the implications for using this technique to develop new therapies for deadly diseases are profound.

In the past scientists used inactivated viruses as a way to deliver corrected copies of the gene to patients. We have blogged about UCLA’s Dr. Don Kohn using this approach to treat children born with SCID, a deadly immune disorder. But that was both time consuming and expensive.

CRISPR, on the other hand, showed that it could be easier to use and less expensive. But getting it to produce enough cells for an effective therapy proved challenging.

The team at Gladstone and UCSF found a way around that by switching from using CRISPR to deliver a double-stranded DNA to correct the gene (which is toxic to cells in large quantities), and instead using CRISPR to deliver a single stranded DNA (you can read the full, very technical description of their approach in the study they published in the journal Nature Biotechnology).

Alex Marson, MD, PhD, director of the Gladstone-UCSF Institute of Genomic Immunology and the senior author of the study, said this more than doubled the efficiency of the process. “One of our goals for many years has been to put lengthy DNA instructions into a targeted site in the genome in a way that doesn’t depend on viral vectors. This is a huge step toward the next generation of safe and effective cell therapies.”

It has another advantage too, according to Gladstone’s Dr. Jonathan Esensten, an author of the study. “This technology has the potential to make new cell and gene therapies faster, better, and less expensive.”

The team has already used this method to generate more than one billion CAR-T cells – specialized immune system cells that can target cancers such as multiple myeloma – and says it could also prove effective in targeting some rare genetic immune diseases.

The California Institute for Regenerative Medicine (CIRM) helped support this research. Authors Brian Shy and David Nguyen were supported by the CIRM:UCSF Alpha Stem Cell Clinic Fellowship program.

First Patient Dosed in Phase 1 Clinical Trial for T1D

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There’s some good news for a company and a therapeutic approach that CIRM has been supporting for many years.

In September 2018, CRISPR Theraputics and ViaCyte entered a partnership to discover, develop and market gene-edited stem cell-derived therapies to treat type 1 diabetes (T1D). Today, they may stand one step closer to their goal. 

Last week the companies jointly announced that they have dosed the first subject in the Phase 1 clinical trial of VCTX210 for the treatment of T1D. VCTX210 is an investigational stem cell-based therapy. It was developed combining CRISPR’s gene-editing technology with ViaCyte’s stem cell expertise to generate pancreatic beta cells that can evade the immune system.

ViaCyte, a regenerative medicine company long backed by CIRM, has developed an implantable device which contains pancreatic endoderm cells that mature over a few months and turn into insulin-producing pancreatic islet cells, the kind destroyed by T1D. 

ViaCyte’s implantable stem cell pouch

Using CRISPR technology, the genetic code of the implanted cells is modified to create beta cells that avoid all recognition by the immune system. This collaboration aims to eliminate the requirement of patients taking daily immunosuppressants to stop the immune system from attacking the implanted cells. 

The first phase of the VCTX210 clinical trial will assess the safety, tolerability, and immune evasion in patients with T1D. 

“We are excited to work with CRISPR Therapeutics and ViaCyte to carry out this historic, first-in-human transplant of gene-edited, stem cell-derived pancreatic cells for the treatment of diabetes designed to eliminate the need for immune suppression,” said James Shapiro, a clinical investigator in the trial. “If this approach is successful, it will be a transformative treatment for patients with all insulin-requiring forms of diabetes.”

CIRM has been a big investor in ViaCyte’s work for many years and has invested more than $72 million in nine different awards.  

Tiny tools for the smallest of tasks, editing genes

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Developing new tools to edit genes

Having the right tools to do a job is important. Try using a large screwdriver to tighten the screws on your glasses and you quickly appreciate that it’s not just the type of tool that’s important, it’s also the size. The same theory applies to gene editing. And now researchers at Stanford have developed a tool that can take on even the tiniest of jobs.

The tool involves the use of CRISPR. You may well have heard about CRISPR. The magazine New Scientist described it this way: “CRISPR is a technology that can be used to edit genes and, as such, will likely change the world.” For example, CIRM is funding research using CRISPR to help children born with severe combined immunodeficiency, a rare, fatal immune disorder.  

There’s just one problem. Right now, CRISPR is usually twinned with a protein called Cas9. Together they are used to remove unwanted genes and insert a corrected copy of the bad gene. However, that CRISPR-Cas9 combination is often too big to fit into all our cells. That may seem hard to understand for folks like me with a limited science background, but trust the scientists, they aren’t making this stuff up.

To address that problem, Dr. Stanley Qi and his team at Stanford created an even smaller version, one they call CasMINI, to enable them to go where Cas9 can’t go. In an article on Fierce Biotech, Dr. Qi said this mini version has some big benefits: “If people sometimes think of Cas9 as molecular scissors, here we created a Swiss knife containing multiple functions. It is not a big one, but a miniature one that is highly portable for easy use.”

How much smaller is the miniature version compared to the standard Cas9? About half the size, 529 amino acids, compared to Cas9’s 1,368 amino acids.”

The team conclude their study in the journal Molecular Cell saying this could have widespread implications for the field: “This provides a new method to engineer compact and efficient CRISPR-Cas effectors that can be useful for broad genome engineering applications, including gene regulation, gene editing, base editing, epigenome editing, and chromatin imaging.”

CIRM-catalyzed spinout files for IPO to develop therapies for genetic diseases

Graphite Bio, a CIRM-catalyzed spinout from Stanford University that launched just 14 months ago has now filed the official SEC paperwork for an initial public offering (IPO). The company was formed by CIRM-funded researchers Matt Porteus, M.D., Ph.D. and Maria Grazia Roncarolo, M.D.

Six years ago, Dr. Porteus and Dr. Roncarolo, in conjunction with Stanford University, received a CIRM grant of approximately $875K to develop a method to use CRISPR gene editing technology to correct the blood stem cells of infants with X-linked severe combined immunodeficiency (X-SCID), a genetic condition that results in a weakened immune system unable to fight the slightest infection.

Recently, Dr. Porteus, in conjunction with Graphite, received a CIRM grant of approximately $4.85M to apply the CRISPR gene editing approach to correct the blood stem cells of patients with sickle cell disease, a condition that causes “sickle” shaped red blood cells. As a result of this shape, the cells clump together and clog up blood vessels, causing intense pain, damaging organs, and increasing the risk of strokes and premature death. The condition disproportionately affects members of the Black and Latin communities.

CIRM funding helped Stanford complete the preclinical development of the sickle cell disease gene therapy and it enabled Graphite to file an Investigational New Drug (IND) application with the U.S. Food and Drug Administration (FDA), one of the last steps necessary before conducting a human clinical trial of a potential therapy. Towards the end of 2020, Graphite got the green light from the FDA to conduct a trial using the gene therapy in patients with sickle cell disease.

In a San Francisco Business Times report, Graphite CEO Josh Lehrer stated that the company’s goal is to create a platform that can apply a one-time gene therapy for a broad range of genetic diseases.

Three UC’s Join Forces to Launch CRISPR Clinical Trial Targeting Sickle Cell Disease

Sickle shaped red blood cells

The University of California, San Francisco (UCSF), in collaboration with UC Berkeley (UCB) and UC Los Angeles (UCLA), have been given permission by the US Food and Drug Administration (FDA) to launch a first-in-human clinical trial using CRISPR technology as a gene-editing technique to cure Sickle Cell Disease.

This research has been funded by CIRM from the early stages and, in a co-funding partnership with theNational Heart, Lung, and Blood Institute under the Cure Sickle Cell initiatve, CIRM supported the work that allowed this program to gain FDA permission to proceed into clinical trials.    

Sickle Cell Disease is a blood disorder that affects around 100,000 people, mostly Black and Latinx people in the US. It is caused by a single genetic mutation that results in the production of “sickle” shaped red blood cells. Normal red blood cells are round and smooth and flow easily through blood vessels. But the sickle-shaped ones are rigid and brittle and clump together, clogging vessels and causing painful crisis episodes, recurrent hospitalization, multi-organ damage and mini-strokes.    

The three UC’s have combined their respective expertise to bring this program forward.

The CRISPR-Cas9 technology was developed by UC Berkeley’s Nobel laureate Jennifer Doudna, PhD. UCLA is a collaborating site, with expertise in genetic analysis and cell manufacturing and UCSF Benioff Children’s Hospital Oakland is the lead clinical center, leveraging its renowned expertise in cord blood and marrow transplantation and in gene therapy for sickle cell disease.

The approach involves retrieving blood stem cells from the patient and, using a technique involving electrical pulses, these cells are treated to correct the mutation using CRISPR technology. The corrected cells will then be transplanted back into the patient.

Dr. Mark Walters

In a news release, UCSF’s Dr. Mark Walters, the principal investigator of the project, says using this new gene-editing approach could be a game-changer. “This therapy has the potential to transform sickle cell disease care by producing an accessible, curative treatment that is safer than the current therapy of stem cell transplant from a healthy bone marrow donor. If this is successfully applied in young patients, it has the potential to prevent irreversible complications of the disease. Based on our experience with bone marrow transplants, we predict that correcting 20% of the genes should be sufficient to out-compete the native sickle cells and have a strong clinical benefit.”

Dr. Maria T. Millan, President & CEO of CIRM, said this collaborative approach can be a model for tackling other diseases. “When we entered into our partnership with the NHLBI we hoped that combining our resources and expertise could accelerate the development of cell and gene therapies for SCD. And now to see these three UC institutions collaborating on bringing this therapy to patients is truly exciting and highlights how working together we can achieve far more than just operating individually.”

The 4-year study will include six adults and three adolescents with severe sickle cell disease. It is planned to begin this summer in Oakland and Los Angeles.

The three UCs combined to produce a video to accompany news about the trial. Here it is:

Scientists use stem cells to create Neanderthal-like “mini-brain”

Alysson R. Muotri, Ph.D.

The evolution of modern day humans has always been a topic that has been shrouded in mystery. Some of what is known is that Neanderthals, an archaic human species that lived on this planet up until about 11,700 years ago, interbred with our species (Homo sapiens) at some point in time. Although their brains were about as big as ours, anthropologists think they must have worked differently due to the fact that they never achieved the sophisticated technology and artistry modern humans have.

Since brains do not fossilize, it has been challenging to see how these two early human species have changed over time. To help answer this question, Dr. Alysson Muotri and his team at UC San Diego created so-called “mini-brains” using stem cells and gene editing technology to better understand how the Neanderthal brain might have functioned.

For this study, Dr. Muotri and his team closely evaluated the differences in genes between modern day humans and Neanderthals. They found a total of 61 different genes, but for this study focused on one in particular that plays a role in influencing early brain development.

Brain organoids that carry a Neanderthal gene.
Image courtesy of the Muotri Lab and UCSD

Using gene editing technology, the team introduced the Neanderthal version of the gene into human stem cells. These stem cells, which have the ability to become various cell types, were then used to create brain cells. These cells eventually formed brain organoids or “mini-brains”, 3D models made of cells that can be used to analyze certain features of the human brain. Although they are far from perfect replicas, they can be used to study physical structure and other characteristics. In a previous CIRM funded study, Dr. Muotri had used “mini-brains” to model an autism spectrum disorder and help test treatments.

Dr. Muotri and his team found that the Neanderthal-like brain organoids looked very different than modern human brain organoids, having a distinctly different shape. Upon further analysis, the team found that modern and Neanderthal-like brain organoids also differed in the way their cells grow. Additionally, the way in which connections between neurons formed as well as the proteins involved in forming these connections differed between the two organoids. Finally, electrical impulses displayed higher activity at earlier stages, but didn’t synchronize in networks in Neanderthal-like brain organoids.

According to Muotri, the neural network changes in Neanderthal-like brain organoids mimic the way newborn primates acquire new abilities more rapidly than human newborns.

In a news release from UCSD, Dr. Muotri discusses the next steps in advancing this research.

“This study focused on only one gene that differed between modern humans and our extinct relatives. Next we want to take a look at the other 60 genes, and what happens when each, or a combination of two or more, are altered. We’re looking forward to this new combination of stem cell biology, neuroscience and paleogenomics.”

The full results of this study were published in Science.

Progress in the fight against Sickle Cell Disease

Marissa Cors, sickle cell disease patient advocate

Last November Marissa Cors, a patient advocate in the fight against Sickle Cell Disease (SCD), told the Stem Cellar “A stem cell cure will end generations of guilt, suffering, pain and early death. It will give SCD families relief from the financial, emotional and spiritual burden of caring someone living with SCD. It will give all of us an opportunity to have a normal life. Go to school, go to work, live with confidence.” With each passing month it seems we are getting closer to that day.

CIRM is funding four clinical trials targeting SCD and another project we are supporting has just been given the green light by the Food and Drug Administration to start a clinical trial. Clearly progress is being made.

Yesterday we got a chance to see that progress. We held a Zoom event featuring Marissa Cors and other key figures in the fight against SCD, CIRM Science Officer Dr. Ingrid Caras and Evie Junior. Evie is a pioneer in this struggle, having lived with sickle cell all his life but now hoping to live his life free of the disease. He is five months past a treatment that holds out the hope of eradicating the distorted blood cells that cause such devastation to people with the disease.

You can listen to his story, and hear about the other progress being made. Here’s a recording of the Zoom event.

You can also join Marissa every week on her live event on Facebook, Sickle Cell Experience Live.

Graphite Bio launches and will prepare for clinical trial based on CIRM-funded research

Josh Lehrer, M.D., CEO of Graphite Bio

This week saw the launch of the 45th startup company enabled by CIRM funding of translational research at California academic institutions. Graphite Bio officially launched with the help of $45M in funding led by bay area venture firms Versant Ventures and Samsara BioCapital to spinout a novel CRISPR gene editing platform from Stanford University to treat severe diseases. Graphite Bio’s lead candidate is for sickle cell disease and it harnesses CRISPR gene correction technology to correct the single DNA mutation in sickle cell disease and to restore normal hemoglobin expression in the red blood cells of sickle cell patients (Learn more about CRISPR from a previous blog post linked here).

Matt Porteus, M.D., Ph.D (left) and Maria Grazia Roncarolo, M.D. (right)
Graphite Bio scientific founders

Matt Porteus, M.D., Ph.D and Maria Grazia Roncarolo, M.D., both from Stanford University, are the company’s scientific founders. Dr. Porteus, Dr. Roncarolo, and the Stanford team are currently supported by a CIRM  late stage preclinical grant  to complete the final preclinical studies and to file an Investigational New Drug application with the FDA, which will enable Graphite Bio to commence clinical studies of the CRISPR sickle cell disease gene therapy candidate in sickle cell patients in 2021.

Josh Lehrer, M.D., was appointed CEO of Graphite Bio and elaborated on the company’s gene editing approach in a news release.

“Our flexible, site-specific approach is extremely powerful and could be used to definitively correct the underlying causes of many severe genetic diseases, and also is applicable to broader disease areas. With backing from Versant and Samsara, we look forward to progressing our novel medicines into the clinic for patients with high unmet needs.”

In a press release, Dr. Porteus take a retrospective look on his preclinical research and its progress towards a clinical trial.

“It is gratifying to see our work on new gene editing approaches being translated into novel therapies. I’m very excited to be working with Versant again on a start-up and I look forward to collaborating with Samsara and the Graphite Bio team to bring a new generation of genetic treatments to patients.”

CIRM’s funding of late stage preclinical projects such this one is critical to its funding model, which de-risks the discovery, translational development and clinical proof of concept of innovative stem cell-based treatments until they can attract industry partnerships. You can learn more about CIRM-enabled spinout companies and CIRM’s broader effort to facilitate industry partnering for its portfolio projects on CIRM’s Industry Alliance Program website.

You can contact CIRM’s Director of Business Development at the email below to learn more about the Industry Alliance Program.

Shyam Patel, Ph.D.
Director, Business Development
Email: spatel@cirm.ca.gov

Gladstone scientists respond to coronavirus pandemic

In these uncertain times, we often look to our top scientists for answers as well as potential solutions. But where does one begin to try and solve a problem of this magnitude? The first logical step is building on the supplies currently available, the work already accomplished, and the knowledge acquired.

This is the approach that the Gladstone Institutes in San Francisco is taking. Various scientists at this institution have shifted their current operations towards helping with the current coronavirus pandemic. These efforts have focused on helping with diagnostics, treatment, and prevention of COVID-19.

Diagnostics

Dr. Jennifer Doudna and Dr. Melanie Ott are collaborating in order to develop an effective method to rapidly diagnose those with COVID-19. Dr. Doudna’s work has focused on CRISPR technology, which we have talked about in detail in a previous blog post, while Dr. Ott has focused on studying viruses. By combining their expertises, these two scientists hope to develop a diagnostic tool capable of delivering rapid results and usable in areas such as airports, ports of entry, and remote communities.

Treatment

Dr. Nevan Krogan has discovered all of the human host cell proteins that COVID-19 interacts with to hijack the cell’s machinery. These proteins serve as new targets for potential drug therapies.

Since the high fatality rate of the virus is driven by lung and heart failure, Dr. Ott, Dr. Bruce Conklin, and Dr. Todd McDevitt will test effects of the virus and potential drug therapies in human lung organoids and human heart cells, both developed from human stem cells.

Dr. Warner Greene, who also focuses on the study of viruses, is screening a variety of FDA-approved drugs to identify those that could be rapidly repurposed as a treatment for COVID-19 patients or even as a preventive for high risk-groups.

Prevention

Dr. Leor Weinberger has developed a new approach to fight the spread of viruses. It is called therapeutic interfering particles (TIPs) and could be an alternative to a vaccine. TIPs are defective virus fragments that mimic the virus but are not able to replicate. They combat the virus by hijacking the cell machinery to transform virus-infected cells into factories that produce TIPS, amplifying the effect of TIPs in stopping the spread of virus. TIPs targeting COVID-19 would transmit along the same paths as the virus itself, and thus provide protection to even the most vulnerable populations.

You can read more about these groundbreaking projects in the news release linked here.