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Novel Gene Therapy Provides Significant Wound Healing in Severe Form of Epidermolysis Bullosa

Recent data presented at the Society for Investigative Dermatology (SID) conference demonstrated that EB-101, a gene therapy provided significant wound healing in patients with Recessive Dystrophic Epidermolysis Bullosa (RDEB), a severe form of epidermolysis bullosa (EB).

RDEB is a subtype of an inherited genetic skin disorder characterized by chronic skin blistering, open and painful wounds, joint contractures, esophageal strictures, pseudosyndactyly, corneal abrasions and a shortened life span. Patients with RDEB lack functional type VII collagen owing to mutations in the gene COL7A1 that encodes for C7 and is the main component of anchoring fibrils, which stabilize the dermal-epidermal basement membrane

EB-101 is an autologous, ex-vivo gene therapy in which COL7A1 is transduced into autologous keratinocytes for the treatment of Recessive Dystrophic Epidermolysis Bullosa (RDEB).

The therapy provided healing (defined as greater than 50% healed) in 100% of Treated Wounds (36/36) at 3 Months; 89% (32/36) at 6 months, 83% (20/24) at 12 months, 88% (21/24) at 24 Months and 100% (6/6) at 36 months Post-Administration. The findings were presented by Abeona Therapeutics’ a leading clinical-stage biopharmaceutical company focused on developing novel gene therapies for life-threatening rare diseases, and the scientific and clinical collaborators at Stanford University School of Medicine, a center of excellence for the treatment of patients with epidermolysis bullosa.

The company also unveiled updated clinical data from the ongoing Phase 1/2 clinical trial for the EB-101 gene therapy program for patients with, along with supportive natural history data for 128 patients with the fatal skin disease.

 “Last week at the SID conference, our EB-101 team of clinical investigators and scientific collaborators presented data from the ongoing Phase 1/2 gene therapy clinical trial and a supportive natural history study of patients with RDEB that highlight the unprecedented wound healing and durable collagen C7 expression of four patients through two years’ post-treatment, including one patient that has continued to see EB-101 treated wounds remain healed three years post-treatment. The relevance of these benefits is highlighted when compared to non-treated control wounds evaluated from the 128-patient natural history study, which showed that RBEB patients suffer chronic and recurrent wounds that do not heal on their own and persist for several years,” said Timothy J. Miller, Ph.D., President and CEO of Abeona Therapeutics.

In the Phase 1/2 trial, EB-101 was administered to non-healing chronic wounds [mean length of time wounds were unhealed (unclosed) was 8.5 years prior to the gene therapy administration] on each subject and assessed for wound healing at predefined time points over years. The primary endpoint of the clinical trial is to assess safety and evaluate wound closure after EB-101 administration compared to control untreated wounds. Secondary endpoints include expression of full-length collagen C7 and restoration of anchoring fibrils at three and six months’ post-administration.

As reflected at the conference by Stanford collaborators, wounds were evaluated at three, six, 12, 24 and 36 months for appearance, durability, and resistance to blistering**:

Wound healing >50%:  defined as >50% closure after EB-101 administration was observed in:
– 100% (36/36 treated wounds, n=6 subjects) at 3 months;
– 89% (32/36 treated wounds, n=6 subjects) at 6 months;
– 83% (20/24 treated wounds, n=4 subjects) at 12 months,
– 88% (21/24 treated wounds, n=4 subjects) at 24 months,
– 100% (6/6 treated wounds, n=1 subject) at 36 months post-administration.

Wound healing >75%: defined as >75% closure after EB-101 administration was observed in:
– 83% (30/36 treated wounds, n=6 subjects) at 3 months;
– 61% (22/36 treated wounds, n=6 subjects) at 6 months;
– 50% (12/24 treated wounds, n=4 subjects) at 12 months;
– 71% (17/24 treated wounds, n=4 subjects) at 24 months;
– 83% (5/6 treated wounds, n=1 subject) at 36 months post-administration.

Collagen VII (C7) expression observed: C7 and morphologically normal NC2 reactive anchoring fibrils – the “zipper” that holds skin onto the underlying tissue and the primary deficit in RDEB patients – have been observed in EB-101 treatments up to two years post administration.

Natural History Study

Data from a supportive natural history study of 1,436 wounds of 128 patients with RDEB, established by Stanford and EBCare Registry, were also presented at the conference. The natural history study characterized both chronic non-healing wounds, defined as an area that does not heal ≥12 weeks, and recurrent wounds, defined as an area that partially heals but then easily re-blisters. Results presented were characterized as 1041 recurrent wounds and 395 chronic open wounds.

Notably, in the natural history study, 13 RDEB patients with a total of 15 chronic wounds were treated with an allograft product, including Apligraf® and Dermagraft®***. Of these wounds treated with allografts, only 7% (1/15 treated wounds) remained healed after 12 weeks, and 0% (0/15 treated wounds) remained healed after 24 weeks. This is a meaningful finding of the natural history study, as there are no approved therapies for RDEB patients that demonstrate significant wound closure after two months post-application.

Investigators at Stanford University are enrolling patients for the ongoing Phase 2 portion of the Phase 1/2 clinical trial (NCT01263379). The EB-101 program has been granted orphan drug designation from the European Medicines Agency (EMA).

Image credit: Samantha Okazaki / Today

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Successfully Treating Genetically Determined Autoimmune Enteritis

Using targeted immunotherapy, doctors have succeeded in curing a type of autoimmune enteritis caused by a recently discovered genetic mutation. This report comes from researchers at the Department of Biomedicine of the University of Basel and University Hospital Basel. Their results raise new possibilities for the management of diarrhea, which is often a side effect of melanoma treatment.

Immunodeficiencies can arise due to gene mutations in immune system proteins. As such mutations rarely occur, these immunodeficiencies often go unrecognized or are detected too late for effective treatment. Currently, there are more than 300 different known genetically determined immunodeficiencies, with new examples being described almost every week.

Prof. Mike Recher’s research group at the Department of Biomedicine of the University of Basel and University Hospital Basel recently discovered a genetic immunodeficiency associated with serious, chronic autoimmune enteritis in an adult patient. Happily, according to the researchers’ report in the Journal of Allergy and Clinical Immunology, they were able not only to describe the new mutation, but also to successfully treat the patient with targeted therapy.

Autoimmune reaction caused by mutation

The patient had a rare mutation in the CTLA-4 protein found on the surface of T-cells. Normally, this protein prevents immune cells from attacking an patient’s own body. However, as it was not functioning adequately due to the mutation, T-cells attacked the patient’s own intestinal cells, causing chronic inflammation. This resulted in the patient suffering from severe diarrhea and weight loss.

These unusual symptoms led the cantonal hospital of Graubünden to refer the patient to the special clinic for immunodeficiency at the University Hospital Basel. Initial immunological investigations suggested a genetically determined dysregulation of the immune system. The new CTLA-4 gene mutation was discovered following subsequent analysis of the entire genome at the University Hospital Zurich. Further investigations showed that the mutation causes reduced CTLA-4 function, which led to increased infiltration of the intestinal mucosa by T-cells and therefore to chronic diarrhea.

Treatment with therapeutic antibodies

Working in close cooperation with University Hospital Basel’s gastroenterology department, the doctors opted for a therapy that uses a new drug from the monoclonal antibody group to prevent the T-cells from penetrating the intestinal mucosa. This drug (vedolizumab) blocks a specific adhesion molecule on the surface of the T-cell and thereby inhibits immune cells from binding themselves to receptors present in the intestine, preventing the T-cells from penetrating the blood vessels in the intestinal tissue. This treatment produced the desired outcome: after three months, the patient’s chronic diarrhea had stopped completely.

Preventing diarrhea in melanoma patients

In some diseases, however, CTLA-4 inhibition can be used therapeutically, as in the treatment of skin cancer (melanoma). The drug Ipilimumab works similarly to the CTLA-4 mutation, meaning that immune system T-cells are no longer properly inhibited and can more efficiently attack the malignant skin cancer cells. One of the side-effects of this therapy is autoimmune intestinal inflammation – analogous to the inflammation that occurs in patients with the CTLA-4 gene mutation. It is possible that melanoma patients, who suffer severe diarrhea due to the inhibition of their CTLA-4 function, will benefit from this new insight, which opens up new therapeutic possibilities for Vedolizumab.

Cooperation between regional hospitals, basic research and university medical departments

This case demonstrates the importance of precise diagnosis of the molecular causes of an illness in enabling targeted, personalized treatment. “In order to expand our knowledge in these areas, doctors in clinics and regional hospitals must be on the alert for unusual disease phenotypes and refer such patients to specialized university hospital clinics for further evaluation,” says study author Mike Recher. “We also need clinical university centers that are closely linked to research laboratories.”

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Asthma Research Unexpectedly Yields New Treatment Approach For Inherited Enzyme Disease

Experiments designed to reveal how a protein protects the lungs from asthma-related damage suggest a new way to treat a rare disease marked by the inability of cells to break down fats, according to a report in EBioMedicine published online Oct. 25.

The study results address Gaucher’s disease, which is caused by a genetic glitch in cell structures called lysosomes that process fats and remove cellular waste. Found mostly in Jews of Eastern and Central European origin, the condition may come with joint pain, blood disorders, enlarged spleens and livers, memory loss, and lung damage.

At a cellular level, Gaucher’s disease is associated with abnormally low production of the protein progranulin, as well as with the misplaced buildup of the enzyme beta-glucocerebrosidase, or GBA, outside lysosomes, instead of inside where it is needed.

Led by researchers from NYU Langone Medical Center, the new study found that a manufactured version of progranulin reversed most effects of Gaucher’s disease in mouse and human cell studies, including GBA accumulation.

“Our results suggest a new way to treat Gaucher’s disease that corrects abnormal enzyme delivery by progranulin to lysosomes, as opposed to current treatment strategies that temporarily replenish lysosomal GBA stores, which are then steadily consumed,” says senior study investigator Chuanju Liu, PhD, a professor in the Departments of Orthopaedic Surgery and Cell Biology at NYU Langone. The research team and NYU Langone hold a patent on related, potential therapies.

Among the study’s other key findings was that progranulin must bind to other molecules to transport the enzyme to lysosomes, specifically the protective “heat shock” protein 70. If unshielded, cellular GBA molecules fold up and stick together outside lysosomes.

Researchers also found that adding synthetic progranulin, or Pcgin, to blood cells obtained from patients with Gaucher’s, led to a 40 percent reduction in GBA clumping within a week. Pcgin was used because it is chemically more stable than progranulin and poses no risk of uncontrolled tumor-like cell growth in test animals, say the authors.

“Our new experiments are the first to explain why reduced progranulin is a key characteristic of Gaucher’s, and why the mice engineered to lack the protein serve as such a good model to test new therapies,” says lead study investigator Jian Jinlong, MD, PhD, an associate research scientist at NYU Langone.

Along with their role in brain disorders, progranulin shortages had been tied by previous research to cell swelling in asthmatic lungs. In the current set of experiments in progranulin-deficient mice, adding Pcgin reduced lung-tissue swelling by as much as 60 percent, an effect seen with current GBA-replacement treatments.

According to Liu, further research is needed to determine the precise mechanism by which progranulin reduces cell swelling, a process that would likely yield even more drug targets for Gaucher’s disease.

Experts estimate that as many as one in 50,000 Americans has some form of Gaucher’s, while one in 500 Jews of Ashkenazi descent has the disease.

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Genome Engineering Paves The Way For Sickle Cell Cure

A team of physicians and laboratory scientists has taken a key step toward a cure for sickle cell disease, using CRISPR-Cas9 gene editing to fix the mutated gene responsible for the disease in stem cells from the blood of affected patients.

For the first time, they have corrected the mutation in a proportion of stem cells that is high enough to produce a substantial benefit in sickle cell patients.

The researchers from the University of California, Berkeley, UCSF Benioff Children’s Hospital Oakland Research Institute (CHORI) and the University of Utah School of Medicine hope to re-infuse patients with the edited stem cells and alleviate symptoms of the disease, which primarily afflicts those of African descent and leads to anemia, painful blood blockages and early death.

“We’re very excited about the promise of this technology,” said Jacob Corn, a senior author on the study and scientific director of the Innovative Genomics Initiative at UC Berkeley. “There is still a lot of work to be done before this approach might be used in the clinic, but we’re hopeful that it will pave the way for new kinds of treatment for patients with sickle cell disease.”

In tests in mice, the genetically engineered stem cells stuck around for at least four months after transplantation, an important benchmark to ensure that any potential therapy would be lasting.

“This is an important advance because for the first time we show a level of correction in stem cells that should be sufficient for a clinical benefit in persons with sickle cell anemia,” said co-author Mark Walters, a pediatric hematologist and oncologist and director of UCSF Benioff Children’s Hospital Oakland’s Blood and Marrow Transplantation Program.

The results will be reported in the Oct. 12 issue of the online journal Science Translational Medicine.

Sickle cell disease is a recessive genetic disorder caused by a single mutation in both copies of a gene coding for beta-globin, a protein that forms part of the oxygen-carrying molecule hemoglobin. This homozygous defect causes hemoglobin molecules to stick together, deforming red blood cells into a characteristic “sickle” shape. These misshapen cells get stuck in blood vessels, causing blockages, anemia, pain, organ failure and significantly shortened lifespan. Sickle cell disease is particularly prevalent in African Americans and the sub-Saharan African population, affecting hundreds of thousands of people worldwide.

The goal of the multi-institutional team is to develop genome engineering-based methods for correcting the disease-causing mutation in each patient’s own stem cells to ensure that new red blood cells are healthy.

The team used CRISPR-Cas9 to correct the disease-causing mutation in hematopoietic stem cells – precursor cells that mature into red blood cells – isolated from whole blood of sickle cell patients. The corrected cells produced healthy hemoglobin, which mutated cells do not make at all.

Future pre-clinical work will require additional optimization, large-scale mouse studies and rigorous safety analysis, the researchers emphasize. Corn and his lab have joined with Walters, an expert in developing curative treatments such as bone marrow transplant and gene therapy for sickle cell disease, to initiate an early-phase clinical trial to test this new treatment within the next five years.

Notably, research groups might be able to apply the approach described in this study to develop treatments for other blood diseases such as β-thalassemia, severe combined immunodeficiency (SCID), chronic granulomatous disease, rare disorders like Wiskott-Aldrich syndrome and Fanconi anemia, and even HIV infection.

“Sickle cell disease is just one of many blood disorders caused by a single mutation in the genome,” Corn said. “It’s very possible that other researchers and clinicians could use this type of gene editing to explore ways to cure a large number of diseases.”

“There is a clear path for developing therapies for certain diseases,” said co-senior author Dana Carroll of the University of Utah, who co-developed one of the first genome editing techniques over a decade ago. “It’s very gratifying to see gene editing technology being brought to practical applications.”

The work is the fruit of the Innovative Genomics Initiative, a joint effort between UC Berkeley and UCSF that aims to correct DNA mutations that underlie human disease using CRISPR-Cas9, a pioneering technology co-developed by scientists at UC Berkeley that has made genome editing easier and more efficient than ever before.

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Uthealth Researchers Identify Genetic Marker For Heart Failure

A team of scientists at The University of Texas Health Science Center at Houston (UTHealth) and Baylor College of Medicine, led by Eric Boerwinkle, Ph.D., Richard Gibbs, Ph.D., and Bing Yu, Ph.D., have identified powerful predictors of congestive heart failure, a major cause of hospitalization and death in the United States. The discovery, published today in Science Advances, was made through an analysis of how gene mutations affect circulating metabolites in the human body.

The human metabolome is a collection of small molecules called metabolites that result from cellular and biological processes in the body and can act as predictors of future disease. Researchers studied how naturally occurring gene mutations can affect metabolites in the genomes of 1,361 African-American participants in the Atherosclerosis Risk in Communities (ARIC) study. ARIC is a longitudinal, population study designed to investigate the origins and predictors of heart disease, stroke and other chronic diseases.

A mutated gene, SLCO1B1, was found to be associated with high levels of blood fatty acid, which is a strong predictor for the development of future heart failure and the mutation itself has a direct effect on heart failure risk.

Because of the aging population, the estimated prevalence and cost of care for heart failure is expected to increase dramatically. By 2030, it’s estimated that more than 8 million people in the United States will have heart failure with $70 billion total costs, according to the American Heart Association. A major risk factor of heart failure is high blood pressure, or hypertension, which is more common among African-Americans.

“The key to heart failure is to identify those at increased risk early. Our hope with this discovery is that we can be more aggressive in treating hypertension if we know someone is genetically predisposed to heart failure,” said Boerwinkle, Kozmetsky Family Chair in Human Genetics and dean of UTHealth School of Public Health.

While the finding was made in a population of African-American participants, the researchers were able to confirm the relationship among European Americans as well.

“African-Americans have higher rates of hypertension, heart failure and mortality. We would expect our findings can help in the prediction and prevention of heart failure among African Americans,” said Yu, assistant professor in the Department of Epidemiology, Human Genetics and Environmental Sciences at UTHealth School of Public Health.

The research builds upon the group’s work on “knockout humans,” which are naturally occurring mutations that inactivate a certain gene. A typical human exome has dozens of these loss-of-function gene variants. Last year, using this technique, the team identified eight new relationships between genes and diseases.

This paper is the first to examine how mutated genes directly affect the metabolome on a genome-wide scale and then go on to influence disease risk. By studying these relationships, the researchers have discovered a new pathway to identify how genes influence disease, according to Boerwinkle.

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High Expression of Short Gene Appears to Contribute to Destructive Eye Pressures in Glaucoma

Scientists have found a variation of the miR-182 gene in patients with primary open-angle glaucoma that results in this overexpression, said Dr. Yutao Liu, vision scientist and human geneticist in the Department of Cellular Biology and Anatomy at the Medical College of Georgia at Augusta University.

Its impact appears to reduce the ability of the cells in the eye’s trabecular meshwork to continually move the clear aqueous humor out of the front of the eye and dump it into the body’s general circulation, said Liu, corresponding author of the study in the journal Investigative Ophthalmology & Visual Science.

“Every 90 minutes, it turns over,” Liu said of the typically balanced process. Since there is no direct blood supply to the front of the eye, the ciliary body just under the colored portion of the eye uses nearby blood to make the fluid to nourish and oxygenate the area, while trabecular meshwork cells near the cornea scoop it up then dump it – along with waste products – back into the circulation.

In glaucoma, there is a problem with outflow, fluid production or both, which results in increased pressure inside the eyeball that damages the optic nerve and can destroy vision. While current therapies help normalize pressure, they typically only slow disease progression.

In the search to learn more about what causes and could better control the disease, the scientists did a genetic analysis of eye tissues and fluids from the National Eye Institute Glaucoma Human Genetics Collaboration Heritable Overall Operational Database, or NEIGHBORHOOD, consortium of 3,853 people with primary open-angle glaucoma and 33,480 healthy controls.

They consistently found higher expression of miR-182 in the different eye tissues they examined from patients with high-tension glaucoma. For example, miR-182 expression in the aqueous humor was twofold higher in high-tension glaucoma patients than controls. Liu notes that since all glaucoma patients were under treatment, their medication’s impact on those levels could not be ruled out, but he suspects that increased expression is a hallmark of the disease state.

Liu recently received a two-year grant from the Bright Focus Foundation (brightfocus.org/ ) that is enabling next-step studies such as exploration of the impact of current drug therapy on miR-182. Elevated miR-182 expression already is associated with premature aging of the eye and, when MCG scientists mimic premature aging by applying hydrogen peroxide, miR-182 levels increase.

Now, they are also are looking at the impact on the trabecular meshwork cells’ ability to take up aqueous humor and deliver it back to the circulation.

Adding color to the fluid is easing their ability to watch its transport, and 3-D imaging is providing additional insight into how the cells are functioning. The additional insight will help answer questions like whether trabecular meshwork cells become stiff and less capable of making the pores that let fluid come onboard for their endless transport task as Liu suspects. He’s also looking at the impact on the ability of trabecular meshwork cells to make and send out fluid-filled pockets called exosomes that may enable the cells to communicate.

Further genetic analysis will also enable identification of additional targets of miR-182. “If we find some targets that constantly change in the eye with glaucoma, then we may be able to find some small chemicals to target those genes in the eye,” he said of these “druggable” targets. Longer-term goals are therapies that more directly target the major pathway in this typically age-related disease.

One known miR-182 target is CHEK2, a known tumor suppressor and suspected genetic risk factor for high-tension glaucoma. CHEK2 has been associated with an enlargement of the tip of the optic nerve that indicates high-pressure damage.

Mutations of miR-182 have been associated with a wide range of disorders, including insomnia and depression, and elevated expression appears to impact genes that regulate the body’s circadian rhythm. It also appears to have a wide impact on normal body regulation from DNA repair to the immune system. In the eye, it’s normally highly expressed in the retina, where it appears to play a role in normal visual function, but has not been clearly associated with disease in this back portion of the eye.

A microRNA, or miRNA, like miR-182 is a small non-coding RNA molecule, which means, rather than actually producing proteins like regular DNA, it helps regulate protein production. There are several hundred of these in each tissue of the body, Liu said.

Known risk factors for glaucoma in addition to age and elevated intraocular pressure, include family history, African ancestry and genetic factors. Primary open-angle glaucoma affects about 1 percent of Americans, according to The Glaucoma Foundation. A percentage of those patients have normal-tension glaucoma, experiencing classic problems such as optic nerve damage and vision loss, despite normal eye pressures. The majority of patients with the miR-182 variation in the study had high-tension glaucoma, Liu noted.

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First Treatment for Spinal Muscular Atrophy up for FDA Approval

A major milestone was reached when nusinersen, an investigational treatment for spinal muscular atrophy (SMA), was shown to significantly improve achievement of motor milestones in babies with infantile-onset SMA, according to an interim analysis of the double-blind, randomized, placebo controlled Phase 3 clinical trial called ENDEAR. Babies born with SMA, a genetic disorder affecting nerves that control muscle movement, cannot hold up their heads, roll over or sit up independently. They often do not survive beyond 2 years of age. Thirty-six centers around the world participated in the study, including Ann & Robert H. Lurie Children’s Hospital of Chicago, which had the highest patient enrollment.

“This landmark study provides the most robust type of evidence that nusinersen, which targets the genetic defect in SMA, safely and effectively helps infants with this condition gain muscle function,” said Nancy Kuntz, MD, Principal Investigator (PI) at Lurie Children’s, Medical Director of Mazza Foundation Neuromuscular Program and Associate Professor of Pediatrics and Neurology at Northwestern University Feinberg School of Medicine. “This might be a promising therapy for this devastating disorder.”

Based on these positive findings and safety profile, the trial will be stopped early and nusinersen will be the first SMA treatment to be filed for FDA approval. Patients in the study will be transitioned into an open label study in which all infants will receive nusinersen. Biogen, the sponsoring company, is working to open a global expanded access program for eligible patients with infantile-onset SMA in the coming months.

“Going forward, we could add SMA to the newborn screening panel and treat infants in the pre-symptomatic phase,” said Leon Epstein, MD, Co-PI at Lurie Children’s, Division Head of Neurology, Medical Director of the Clinical Research Unit of Stanley Manne Children’s Research Institute at Lurie Children’s, and Professor of Pediatrics and Neurology at Northwestern University Feinberg School of Medicine.

Due to a genetic defect, infants with SMA do not produce enough survival motor neuron (SMN) protein, which is critical for the maintenance of motor nerve cells. Nusinersen is designed to increase production of fully functional SMN protein by regulating gene expression. The investigational treatment is delivered to the fluid around the spine by lumbar puncture, or spinal tap. Repeated doses are needed.

“The success we saw in the trial is incredibly exciting for families of infants with SMA, as well as for physicians who care for these children,” said Kuntz.

Research at Ann & Robert H. Lurie Children’s Hospital of Chicago is conducted through the Stanley Manne Children’s Research Institute. The Manne Research Institute is focused on improving child health, transforming pediatric medicine and ensuring healthier futures through the relentless pursuit of knowledge.

Lurie Children’s is ranked as one of the nation’s top children’s hospitals in the U.S.News & World Report. It is the pediatric training ground for Northwestern University Feinberg School of Medicine. Last year, the hospital served more than 174,000 children from 50 states and 48 countries.