For children born with severe combined immunodeficiency (SCID) life can be very challenging. SCID means they have no functioning immune system, so even a simple infection can prove life threatening. Left untreated, children with SCID often die in the first few years of life.
There are stem cell/gene therapies funded by the California Institute for Regenerative Medicine (CIRM), such as ones at UCLA and UCSF/St. Judes, but an alternative method of treating, and even curing the condition, is a bone marrow or hematopoietic stem cell transplant (HCT). This replaces the child’s blood supply with one that is free of the SCID mutation, which helps restore their immune system.
However, current HCT methods involve the use of chemotherapy or radiation to destroy the patient’s own unhealthy blood stem cells and make room for the new, healthy ones. This approach is toxic and complex and can only be performed by specialized teams in major medical centers, making access particularly difficult for poor and underserved communities.
To change that, Dr. Judy Shizuru at Stanford University, with CIRM funding, developed an antibody that can direct the patient’s own immune cells to kill diseased blood stem cells, creating the room needed to transplant new, healthy cells. The goal was to make stem cell transplants safer and more effective for the treatment of many life-threatening blood disorders.
That approach, JSP191, is now being championed by Jasper Therapeutics and they just got some very good news from the Food and Drug Administration (FDA). The FDA has granted JSP191 Fast Track Designation, which can speed up the review of therapies designed to treat serious conditions and fill unmet medical needs.
In a news release, Ronald Martell, President and CEO of Jasper Therapeutics, said this is good news for the company and patients: “This new Fast Track designation recognizes the potential role of JSP191 in improving clinical outcomes for these patients and will allow us to more closely work with the FDA in the upcoming months to determine a path toward a Biologics License Application (BLA) submission.”
Getting a BLA means Jasper will be able to market the antibody in the US and make it available to all those who need it.
This is the third boost from the FDA for Jasper. Previously the agency granted JSP191 both Orphan and Rare Pediatric Disease designations. Orphan drug designation qualifies sponsors for incentives such as tax credits for clinical trials. Rare Pediatric Disease designation means that if the FDA does eventually approve JSP191, then Jasper can apply to receive a priority review of an application to use the product for a different disease, such as someone who is getting a bone marrow transplant for sickle cell disease or severe auto immune diseases.
Dr. Rosa Bacchetta on the right with Brian Lookofsky (left) and Taylor Lookofsky after CIRM funded Dr. Bacchetta’s work in October 2019. Taylor has IPEX syndrome
It’s always lovely to end the week on a bright note and that’s certainly the case this week, thanks to some encouraging news about CIRM-funded research targeting blood disorders that affect the immune system.
Stanford’s Dr. Rosa Bacchetta and her team learned that their proposed therapy for IPEX Syndrome had been given the go-ahead by the Food and Drug Administration (FDA) to test it in people in a Phase 1 clinical trial.
IPEX Syndrome (it’s more formal and tongue twisting name is Immune dysregulation Polyendocrinopathy Enteropathy X-linked syndrome) is a life-threatening disorder that affects children. It’s caused by a mutation in the FOXP3 gene. Immune cells called regulatory T Cells normally function to protect tissues from damage but in patients with IPEX syndrome, lack of functional Tregs render the body’s own tissues and organs to autoimmune attack that could be fatal in early childhood.
Current treatment options include a bone marrow transplant which is limited by available donors and graft versus host disease and immune suppressive drugs that are only partially effective. Dr. Rosa Bacchetta and her team at Stanford will use gene therapy to insert a normal version of the FOXP3 gene into the patient’s own T Cells to restore the normal function of regulatory T Cells.
This approach has already been accorded an orphan drug and rare pediatric disease designation by the FDA (we blogged about it last year)
Orphan drug designation is a special status given by the Food and Drug Administration (FDA) for potential treatments of rare diseases that affect fewer than 200,000 in the U.S. This type of status can significantly help advance treatments for rare diseases by providing financial incentives in the form of tax credits towards the cost of clinical trials and prescription drug user fee waivers.
Under the FDA’s rare pediatric disease designation program, the FDA may grant priority review to Dr. Bacchetta if this treatment eventually receives FDA approval. The FDA defines a rare pediatric disease as a serious or life-threatening disease in which the serious or life-threatening manifestations primarily affect individuals aged from birth to 18 years and affects fewer than 200,000 people in the U.S.
Congratulations to the team and we wish them luck as they begin the trial.
Dr. Donald Kohn, Photo courtesy UCLA
Someone who needs no introduction to regular readers of this blog is UCLA’s Dr. Don Kohn. A recent study in the New England Journal of Medicine highlighted how his work in developing a treatment for severe combined immune deficiency (SCID) has helped save the lives of dozens of children.
Now a new study in the journal Blood shows that those benefits are long-lasting, with 90% of patients who received the treatment eight to 11 years ago still disease-free.
In a news release Dr. Kohn said: “What we saw in the first few years was that this therapy worked, and now we’re able to say that it not only works, but it works for more than 10 years. We hope someday we’ll be able to say that these results last for 80 years.”
Ten children received the treatment between 2009 and 2012. Nine were babies or very young children, one was 15 years old at the time. That teenager was the only one who didn’t see their immune system restored. Dr. Kohn says this suggests that the therapy is most effective in younger children.
Dr. Kohn has since modified the approach his team uses and has seen even more impressive and, we hope, equally long-lasting results.
Rocket Pharmaceuticals, a company that specializes in developing genetic therapies for rare childhood disorders, just got a big boost from the European Medicines Agency (EMA). They were given a Priority Medicines (PRIME) designation for their therapy for Leukocyte Adhesion Deficiency-1 (LAD-1).
CIRM is funding ($6.56 million) Rocket’s clinical trial for LAD-I, an immune disorder that leaves patients vulnerable to repeated infections that often results in death within the first two years of life. The therapy involves taking some of the child’s own blood stem cells and, in the lab, correcting the mutation that causes LAD-I, then returning those cells to the patient. Hopefully those blood stem cells then create a new, healthy blood supply and repair the immune system.
The therapy, called RP-L201, is already showing promise in the clinical trial, hence the PRIME designation. The program was set up to help speed up development and evaluation of therapies that could help patients who have limited treatment options. Getting a PRIME designation means it is considered a priority by EMA and could reach patients sooner.
In the US, Rocket has won similar recognition from the Food and Drug Administration (FDA) and has been granted Regenerative Medicine Advanced Therapy (RMAT), Rare Pediatric Disease, and Fast Track designations.
In a news release Kinnari Patel, President and Chief Operating Officer of Rocket, said the designation showed that regulators understand the urgent need to develop a therapy for patients with LAD-1. “More than half of LAD-I patients suffer with a severe variant in which mortality occurs in up to 75% of young children who don’t receive a successful bone marrow transplant by the age of two. Securing all possible accelerated designations will enable us to collaborate with both the FDA and EMA to speed the development and delivery of a potential treatment for these patients. We look forward to sharing initial Phase 2 data from our potentially registration-enabling LAD-I trial in the second quarter of 2021.”
That trial has now completed enrolling patients (nine altogether) but their treatments are not yet complete. LAD-1 patients with severe disease have low levels of a key protein called CD18, usually less than 2%. Of the first three patients treated in this trial CD18 levels are all higher than the 4-10% threshold considered necessary for these children to survive into adulthood. Another encouraging sign is that there were no serious side effects from the therapy.
Obviously there is still a long way to go before we know if this therapy really works, but the PRIME designation – along with the similar ones in the US – are recognition that this is a very promising start.
The gold standard for any new therapy in the U.S. is approval by the Food and Drug Administration (FDA). This approval clears the therapy for sale and often also means it will be covered by insurance. But along the way there are other designations that can mean a lot to a company developing a new approach to a deadly disease.
That’s what recently happened with Mustang Bio’s MB-107. The therapy was given Orphan Drug Designation for the treatment of X-linked Severe Combined Immunodeficiency (SCID) also known as “bubble baby disease”, a rare but deadly immune disorder affecting children. This is the same therapy that CIRM is funding in a clinical trial we’ve blogged about in the past.
Getting Orphan Drug Designation can be a big deal. It is given to therapies intended for the treatment, diagnosis or prevention of rare diseases or disorders that affect fewer than 200,000 people in the U.S. It comes with some sweet incentives, such as tax credits toward the cost of clinical trials and prescription drug user fee waivers. And, if the product becomes the first in its class to get FDA approval for a particular disease, it is entitled to seven years of market exclusivity, which is independent from intellectual property protection.
This is not the first time Mustang Bio’s MB-107 has been acknowledged as a potential gamechanger. It’s also been given three other classifications both here in the US and in Europe.
Rare Pediatric Disease Designation: this also applies to treatments for diseases affecting fewer than 200,000 people in the US that have the potential to provide clinically meaningful benefits to patients. It provides the company with a “voucher” that they can use to apply for priority review for another therapy they are developing. The hope is that this will encourage companies to develop treatments for rare childhood diseases that might not otherwise be profitable.
Regenerative Medicine Advanced Therapy (RMAT) designation: this allows for faster, more streamlined approvals of regenerative medicine products
Advanced Therapy Medicinal Product classification: this is granted by the European Medicines Agency (EMA) to medicines that are based on genes, tissues or cells and can offer groundbreaking opportunities for the treatment of disease.
Of course, none of these designations are a guarantee that Mustang Bio’s MB-107 will ultimately get FDA approval, but they’re a pretty good indication that a lot of people have confidence they’ll get there.
Welcome back to our “Throwback Thursday” series on the Stem Cellar. Over the years, we’ve accumulated an arsenal of exciting stem cell stories about advances towards stem cell-based cures for serious diseases. Today we’re featuring stories about the progress of CIRM-funded clinical trials for the treatment of a devastating, usually fatal, primary immune disease that strikes newborn babies.
Evie, a former “bubble baby” enjoying life by playing inside a giant plastic bubble
‘Bubble baby disease’ will one day be a thing of the past. That’s a bold statement, but I say it with confidence because of the recent advancements in stem cell gene therapies that are curing infants of this life-threatening immune disease.
The scientific name for ‘bubble baby disease’ is severe combined immunodeficiency (SCID). It prevents the proper development of important immune cells called B and T cells, leaving newborns without a functioning immune system. Because of this, SCID babies are highly susceptible to deadly infections, and without treatment, most of these babies do not live past their first year. Even a simple cold virus can be fatal.
Scientists are working hard to develop stem cell-based gene therapies that will cure SCID babies in their first months of life before they succumb to infections. The technology involves taking blood stem cells from a patient’s bone marrow and genetically correcting the SCID mutation in the DNA of these cells. The corrected stem cells are then transplanted back into the patient where they can grow and regenerate a healthy immune system. Early-stage clinical trials testing these stem cell gene therapies are showing very encouraging results. We’ll share a few of these stories with you below.
CIRM-funded trials for SCID
CIRM is funding three clinical trials, one from UCLA, one at Stanford and one from UCSF & St. Jude Children’s Research Hospital, that are treating different forms of SCID using stem cell gene therapies.
Adenosine Deaminase-Deficient SCID
The first trial is targeting a form of the disease called adenosine deaminase-deficient SCID or ADA-SCID. Patients with ADA-SCID are unable to make an enzyme that is essential for the function of infection-fighting immune cells called lymphocytes. Without working lymphocytes, infants eventually are diagnosed with SCID at 6 months. ADA-SCID occurs in approximately 1 in 200,000 newborns and makes up 15% of SCID cases.
CIRM is funding a Phase 2 trial for ADA-SCID that is testing a stem cell gene therapy called OTL-101 developed by Dr. Don Kohn and his team at UCLA and a company called Orchard Therapeutics. 10 patients were treated in the trial, and amazingly, nine of these patients were cured of their disease. The 10th patient was a teenager who received the treatment knowing that it might not work as it does in infants. You can read more about this trial in our blog from earlier this year.
In a recent news release, Orchard Therapeutics announced that the US Food and Drug Administration (FDA) has awarded Rare Pediatric Disease Designation to OTL-101, meaning that the company will qualify for priority review for drug approval by the FDA. You can read more about what this designation means in this blog.
X-linked SCID
The second SCID trial CIRM is funding is treating patients with X-linked SCID. These patients have a genetic mutation on a gene located on the X-chromosome that causes the disease. Because of this, the disease usually affects boys who have inherited the mutation from their mothers. X-linked SCID is the most common form of SCID and appears in 1 in 60,000 infants.
UCSF and St. Jude Children’s Research Hospital are conducting a Phase 1/2 trial for X-linked SCID. The trial, led by Dr. Brian Sorrentino, is transplanting a patient’s own genetically modified blood stem cells back into their body to give them a healthy new immune system. Patients do receive chemotherapy to remove their diseased bone marrow, but doctors at UCSF are optimizing low doses of chemotherapy for each patient to minimize any long-term effects. According to a UCSF news release, the trial is planning to treat 15 children over the next five years. Some of these patients have already been treated and we will likely get updates on their progress next year.
CIRM is also funding a third clinical trial out of Stanford University that is hoping to make bone marrow transplants safer for X-linked SCID patients. The team, led by Dr. Judy Shizuru, is developing a therapy that will remove unhealthy blood stem cells from SCID patients to improve the survival and engraftment of healthy bone marrow transplants. You can read more about this trial on our clinical trials page.
SCID Patients Cured by Stem Cells
These clinical trial results are definitely exciting, but what is more exciting are the patient stories that we have to share. We’ve spoken with a few of the families whose children participated in the UCLA and UCSF/St. Jude trials, and we asked them to share their stories so that other families can know that there is hope. They are truly inspiring stories of heartbreak and joyful celebration.
Evie is a now six-year-old girl who was diagnosed with ADA-SCID when she was just a few months old. She is now cured thanks to Don Kohn and the UCLA trial. Her mom gave a very moving presentation about Evie’s journey at the CIRM Bridges Trainee Annual Meeting this past July. You can watch the 20-minute talk below:
Ronnie’s story
Ronnie: Photo courtesy Pawash Priyank
Ronnie, who is still less than a year old, was diagnosed with X-linked SCID just days after he was born. Luckily doctors told his parents about the UCSF/St. Jude trial and Ronnie was given the life-saving stem cell gene therapy before he was six months old. Now Ronnie is building a healthy immune system and is doing well back at home with his family. Ronnie’s dad Pawash shared his families moving story at our September Board meeting and you can watch it here.
Our mission at CIRM is to accelerate stem cell treatments to patients with unmet medical needs. We hope that by funding promising clinical trials like the ones mentioned in this blog, that one day soon there will be approved stem cell therapies for patients with SCID and other life-threatening diseases.
If you have read our 2016 Annual Report (and if you haven’t you should, it’s brilliant) or just seen the cover you’ll know that it features very prominently a young girl named Evie Padilla Vaccaro.
Evie was born with Severe Combined Immunodeficiency or SCID – also known as “bubble baby disease”; we’ve written about it here. SCID is a rare but deadly immune disorder which leaves children unable to fight off simple infections. Many children with SCID die in the first few years of life.
Fortunately for Evie and her family, Dr. Don Kohn and his team at UCLA, working with a UK-based company called Orchard Therapeutics Ltd., have developed a treatment called OTL-101. This involves taking the patient’s own blood stem cells, genetically modifying them to correct the SCID mutation, and then returning the cells to the patient. Those modified cells create a new blood supply, and repair the child’s immune system.
Evie was treated with OTL-101 when she was a few months old. She is cured. And she isn’t the only one. To date more than 40 children have been treated with this method. All have survived and are doing well.
FDA acknowledgement
Because of that success the US Food and Drug Administration (FDA) has granted OTL-101 Rare Pediatric Disease Designation. This status is given to a treatment that targets a serious or life-threatening disease that affects less than 200,000 people, most of whom are under 18 years of age.
The importance of the Rare Pediatric Disease Designation is that it gives the company certain incentives for the therapy’s development, including priority review by the FDA. That means if it continues to show it is safe and effective it may have a faster route to being made more widely available to children in need.
In a news release Anne Dupraz, PhD, Orchard’s Chief Regulatory Officer, welcomed the decision:
“Together with Orphan Drug and Breakthrough Therapy Designations, this additional designation is another important development step for the OTL-101 clinical program. It reflects the potential of this gene therapy treatment to address the significant unmet medical need of children with ADA-SCID and eligibility for a Pediatric Disease Priority Review voucher at time of approval.”
Creating a trend
This is the second time in less than two weeks that a CIRM-funded therapy has been awarded Rare Pediatric Disease designation. Earlier this month Capricor Therapeutics was given that status for its treatment for Duchenne Muscular Dystrophy.
Two other CIRM-funded clinical trials – Humacyte and jCyte – have been given Regenerative Medicine Advanced Therapy Designation (RMAT) by the FDA. This makes them eligible for earlier and faster interactions with the FDA, and also means they may be able to apply for priority review and faster approval.
All these are encouraging signs for a couple of reasons. It suggests that the therapies are showing real promise in clinical trials. And it shows that the FDA is taking steps to encourage those therapies to advance as quickly – and safely of course – as possible.
Credit where credit is due
In the past we have been actively critical of the FDA’s sluggish pace in moving stem cell therapies out of the lab and into clinical trials where they can be tested in people. So when the FDA does show signs of changing the way it works it’s appropriate that that we are actively supportive.
Getting these designations is, of course, no guarantee the therapies will ultimately prove to be successful. But if they are, creating faster pathways means they can get to patients, the people who really need them, at a much faster pace.
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