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Feb 16, 2016
DALLAS – Feb. 16, 2016 – Researchers at UT Southwestern Medical Center have identified synthetic RNA and DNA that reverses the protein deficiency causing Friedreich’s ataxia, a neurological disease for which there is currently no cure.
Friedreich’s ataxia results from modifications to DNA sequences that prevent cells from producing enough of a needed protein called frataxin. The lack of frataxin can result in a variety of problems that include loss of muscle control, fatigue, vision or hearing impairment, slurred speech, and serious heart conditions.
Dr. David Corey, Professor of Pharmacology and Biochemistry
Using synthetic RNA or DNA, researchers have identified a way to allow normal frataxin production to resume.
“The synthetic DNA or RNA prevents the mutant sequence from bending back and blocking the frataxin gene. This action activates the frataxin gene, which then makes frataxin RNA and protein at normal levels,” saidDr. David Corey, Professor of Pharmacology and Biochemistry. “In addition, our approach is selective for targeting the frataxin gene and does not affect other genes.”
In contrast to the CRISPR genomic editing technique, which requires modifications to genes, the molecules in this study are synthetic. The DNA and RNA belong to classes of molecules that already are being used clinically, making development of a new therapy more straightforward, said Dr. Corey, who holds the Rusty Kelley Professorship in Medical Science.
For use in Friedreich’s ataxia, the remaining challenge will be to adequately deliver the synthetic molecules to tissues that are affected by the disease, but those challenges are being addressed by existing clinical programs targeting Huntington’s disease and spinal muscular atrophy, Dr. Corey said.
About one in 50,000 people have Friedreich’s ataxia, and typical onset is between 5 and 18 years of age, according to the National Institute of Neurological Disorders and Stroke. The disease is caused by cells making too little of the protein frataxin, although the proteins that are made are considered normal.
“The problem arises because of a mutation within the frataxin gene that does not code for protein. In this case, the mutation causes the synthesis of a longer piece of RNA. This longer sequence binds the DNA and gums up the works, blocking RNA production needed to produce the frataxin protein,” Dr. Corey said.
The findings appear in the journal .
Other UT Southwestern authors include Dr. Masayuki Matsui, Assistant Instructor of Pharmacology, and Liande Li, research scientist in Pharmacology.
Support for the research came from RaNA Pharmaceuticals, the Robert A. Welch Foundation, the Friedreich’s Ataxia Research Alliance and the National Institute of General Medical Sciences.
UT Southwestern has established the Peter O’Donnell Jr. Brain Institute, a comprehensive initiative dedicated to better understanding the basic molecular workings of the brain and applying these discoveries to the prevention and treatment of brain diseases and injuries.
UT Southwestern, one of the premier academic medical centers in the nation, integrates pioneering biomedical research with exceptional clinical care and education. The institution’s faculty has included six who have been awarded Nobel Prizes since 1985. The faculty of almost 2,800 is responsible for groundbreaking medical advances and is committed to translating science-driven research quickly to new clinical treatments. UT Southwestern physicians provide medical care in about 80 specialties to more than 100,000 hospitalized patients and oversee approximately 2.2 million outpatient visits a year.
Media Contact: Gregg
Friedreich ataxia is not only a GAA repeats expansion disorder: implications for molecular testing and counselling
· Tomasz Mazurczak
· Tomasz Zajkowski
· Renata Tataj
· Paulina Górka-Skoczylas
· Katarzyna Połatyńska
· Łukasz Kępczyński
· Mariusz Stasiołek
· Jerzy Bal
Friedreich ataxia (FRDA) is the most common hereditary ataxia. It is an autosomal recessive disorder caused by mutations of the FXN gene, mainly the biallelic expansion of the (GAA)n repeats in its first intron. Heterozygous expansion/point mutations or deletions are rare; no patients with two point mutations or a point mutation/deletion have been described, suggesting that loss of the FXNgene product, frataxin, is lethal. This is why routine FRDA molecular diagnostics is focused on (GAA)n expansion analysis. Additional tests are considered only in cases of heterozygous expansion carriers and an atypical clinical picture. Analyses of the parent’s carrier status, together with diagnostic tests, are performed in rare cases, and, because of that, we may underestimate the frequency of deletions. Even though FXN deletions are characterised as ‘exquisitely rare,’ we were able to identify one case (2.4 %) of a (GAA)n expansion/exonic deletion in a group of 41 probands. This was a patient with very early onset of disease with rapid progression of gait instability and hypertrophic cardiomyopathy. We compared the patient’s clinical data to expansion/deletion carriers available in the literature and suggest that, in clinical practice, the FXN deletion test should be taken into account in patients with early-onset, rapid progressive ataxia and severe scoliosis.
Combined Cerebellar Proton MR Spectroscopy and DWI Study of Patients with Friedreich’s Ataxia
· Laura Ludovica Gramegna
· David Neil Manners
· Antonella Pini
· Rita Rinaldi
· Stefano Zanigni
· Claudio Bianchini
· Stefania Evangelisti
· Filippo Fortuna
· and 3 more
Friedreich’s ataxia (FRDA) is the commonest autosomal recessive ataxia, caused by GAA triplet expansion in the frataxin gene. Neuropathological studies in FRDA demonstrate that besides the primary neurodegeneration of the dorsal root ganglia, there is a progressive atrophy of the cerebellar dentate nucleus. Diffusion-weighted imaging (DWI) detected microstructural alterations in the cerebellum of FRDA patients. To investigate the biochemical basis of these alterations, we used both DWI and proton MR spectroscopy (1H-MRS) to study the same cerebellar volume of interest (VOI) including the dentate nucleus. DWI and 1H-MRS study of the left cerebellar hemisphere was performed in 28 genetically proven FRDA patients and 35 healthy controls. In FRDA mean diffusivity (MD) values were calculated for the same 1H-MRS VOI. Clinical severity was evaluated using the International Cooperative Ataxia Rating Scale (ICARS). FRDA patients showed a significant reduction of N-acetyl-aspartate (NAA), a neuroaxonal marker, and choline (Cho), a membrane marker, both expressed relatively to creatine (Cr), and increased MD values. In FRDA patients NAA/Cr negatively correlated with MD values (r = −0.396, p = 0.037) and with ICARS score (r = −0.669, p < 0.001). Age-normalized NAA/Cr loss correlated with the GAA expansion (r = −0.492,p = 0.008). The reduced cerebellar NAA/Cr in FRDA suggests that neuroaxonal loss is related to the microstructural changes determining higher MD values. The correlation between NAA/Cr and the severity of disability suggests that this biochemical in vivo MR parameter might be a useful biomarker to evaluate therapeutic interventions.
Recently the intrathecal administration has been proposed as part of a
hopeful therapy for FA (Intrathecal
delivery of frataxin mRNA encapsulated in lipid nanoparticles to dorsal
root ganglia as a potential therapeutic for Friedreich’s ataxia).
This paper shows (in laboratory animals) the feasibility of the use of
intrathecal administration to reach efficiently the dorsal root ganglia.
Long-term effect of epoetin alfa on clinical and biochemical markers in friedreich ataxia
1. Francesco Saccà MD,
2. Giorgia Puorro MBiol,
3. Angela Marsili MBiol,
4. Antonella Antenora MD,
5. Chiara Pane MD,
6. Carlo Casali MD,
7. Christian Marcotulli MD,
8. Giovanni Defazio MD,
9. Daniele Liuzzi MD,
10. Chiara Tatillo MD,
11. Donata Maria Cambriglia MD,
12. Giuseppe Schiano di Cola MD,
13. Luigi Giuliani MD,
14. Vincenzo Guardasole MD, PhD,
15. Andrea Salzano MD,
16. Antonio Ruvolo MD, PhD,
17. Anna De Rosa MD, PhD,
18. Antonio Cittadini MD, PhD,
19. Giuseppe De Michele MDand
20. Alessandro Filla MD
Friedreich ataxia is an autosomal recessive disease with no available therapy. Clinical trials with erythropoietin in Friedreich ataxia patients have yielded conflicting results, and the long-term effect of the drug remains unknown.
We designed a double-blind, placebo-controlled, multicenter trial to test the efficacy of epoetin alfa on 56 patients with Friedreich ataxia. The primary endpoint of the study was the effect of epoetin alfa on peak oxygen uptake (VO max) at the cardiopulmonary exercise test. Secondary endpoints were frataxin levels in peripheral blood mononuclear cells, improvement in echocardiography findings, vascular reactivity, neurological progression, upper limb dexterity, safety, and quality of life. Epoetin alfa or placebo (1:1 ratio) was administered subcutaneously at a dose of 1200 IU/Kg of body weight every 12 weeks for 48 weeks.
A total of 56 patients were randomized; 27 completed the study in the active treatment group, and 26 completed the study in the placebo group[KG1]. VO max was not modified after treatment (0.01 [−0.04 to 0.05]; P = .749), as well as most of the secondary endpoint measures, including frataxin. The 9-hole peg test showed a significant amelioration in the treatment group (−17.24 sec. [−31.5 to −3.0]; P = .018). The treatment was safe and well tolerated.
Intrathecal delivery of frataxin mRNA encapsulated in lipid nanoparticles to dorsal root ganglia as a potential therapeutic for Friedreich’s ataxia
Understanding the Role of Mitochondrial Pathophysiology in Friedreich's Ataxia
Agilis Biotherapeutics and Waisman Biomanufacturing Enter Into Exclusive Manufacturing Agreement for Friedreich’s Ataxia Gene Therapy
Waisman to provide global supply of Agilis’ novel AGIL-FA gene therapy
February 18, 2016 07:30 AM Eastern Standard Time
CAMBRIDGE, Mass. & MADISON, Wis.--(BUSINESS WIRE)--Agilis Biotherapeutics, LLC (Agilis), a biotechnology company advancing innovative gene therapies for rare genetic diseases that affect the central nervous system (CNS), and Waisman Biomanufacturing, a non-profit gene and cell therapy development and manufacturing group located at the UW-Madison Waisman Center, (Waisman) announced today that the companies have entered into an exclusive partnership agreement for the production of Agilis’ novel gene therapy product, AGIL-FA, for the treatment of Friedreich’s ataxia (FA). FA is a debilitating multi-system disease arising from mutation of the FXN gene. It is the most common inherited ataxia, with 1 in every 100 people being carriers of a mutated FXN gene. FA typically arises between the ages of 5 and 15 and manifests as difficulty with balance and coordination. Over time, the disease progresses to an array of neurological symptoms and life-altering changes in mobility, energy, speech, hearing, and other body systems including the cardiovascular system, which collectively reduce longevity in many cases.
“Our partnership with Waisman is an important step in advancing our AGIL-FA gene therapy for the potential treatment of the neurological symptoms in Friedreich’s ataxia patients”
Following the completed evaluation and selection of the lead therapeutic candidate for FA, AGIL-FA, Agilis has completed molecular characterization and initial proof-of-concept and biodistribution studies of AGLIL-FA in advance of submission of an Investigational New Drug (IND) application to the U.S. Food and Drug Administration. The FXN gene construct used in AGIL-FA was optimized and developed in partnership with Intrexon Corporation (NYSE: XON).
Under the terms of the agreement, Waisman will utilize its personnel, facilities and proprietary processes to manufacture GLP material for non-clinical studies, cGMP material for non-clinical and clinical studies, and potential future commercial supply should AGIL-FA be successfully developed and approved. Agilis and Waisman will each provide team experts to contribute to the overall execution of the full range of manufacturing, quality and regulatory activities.
“Our partnership with Waisman is an important step in advancing our AGIL-FA gene therapy for the potential treatment of the neurological symptoms in Friedreich’s ataxia patients,” said Dr. Mark Pykett, Agilis President and CEO. “Waisman is a leading manufacturer of biological products, with extensive experience and a strong track record in the production of innovative medical products. In partnering with Waisman to leverage their proprietary systems, organizational expertise, and extensive infrastructure, Agilis has solidified a key strategic component in the near-term and long-term development and commercialization of AGIL-FA. We are pleased to partner with such a reputable organization as Waisman to ensure high quality, scalable manufacturing of the product.”
Founded in 2001, Waisman Biomanufacturing, a non-profit entity of the Waisman Center and the University of Wisconsin, currently operates a 15,000 square foot biologics manufacturing facility with eight cGMP compliant cleanroom areas to accommodate clinical production of mammalian and microbial therapies and aseptic filling of final products. The Waisman Quality System and cleanroom facility are designed to maximize regulatory compliance and environmental quality.
Dr. Derek Hei, Director of Waisman, commented, “Our partnership with Agilis is reflective of Waisman’s mission to provide high quality cGMP biologic products to our partners and to assist with the advancement of innovative medicines to enhance the treatment of human diseases. We are pleased to collaborate with Agilis on its exciting gene therapy product for Friedreich’s ataxia and to facilitate supply of the product for the sequence of development stages required for its approval and ultimate commercialization.”
About Friedreich’s Ataxia
Friedreich’s ataxia (FA) is an inherited neuromuscular disorder most commonly caused by a single genetic defect in the FXN gene that leads to reduced production of frataxin, a mitochondrial protein that is important for iron metabolism. FA results in a physically debilitating, life-shortening condition and is the most common hereditary ataxia, with an estimated 5,000 to 10,000 patients in the U.S. (i.e., one in every 50,000 people). Both male and female children can inherit the disorder. Symptoms of FA include progressive loss of coordination and muscle strength, which lead to the full-time use of a wheelchair; scoliosis (which often requires surgical intervention); diabetes mellitus; hearing and vision impairment; serious heart conditions; and premature death. Current FA therapies are primarily focused on symptomatic relief, and there are no FDA-approved drugs to treat the cause of FA.
About Agilis Biotherapeutics
Agilis is advancing innovative gene therapies designed to provide long-term efficacy for patients with debilitating, often fatal, rare genetic diseases that affect the central nervous system. Agilis' therapies are engineered to impart sustainable clinical benefits, and potentially a functional cure, by inducing persistent expression of a therapeutic gene. The Company’s technology is aimed at the precise targeting and restoration of a lost gene function, while avoiding unintended off-target effects. Agilis' integrated strategy increases the efficiency of developing DNA therapeutics into safe, targeted gene therapies that achieve long-term efficacy and enable patients to remain asymptomatic without continuous invasive treatment. Agilis’ rare disease programs are focused on gene therapy for AADC Deficiency, Friedreich’s ataxia, Angelman syndrome, and Fragile X syndrome, rare genetic diseases that include severe neurological deficits and result in physically debilitating conditions.
UNC gene therapy spinout Bamboo Therapeutics raises $49.5M Series A
/ Feb 11, 2016 at 12:28 PM
North Carolina gene therapy startupBamboo Therapeutics has raised a stunning $49.5 million, according to an SEC filing. The startup is focused on advancing the work of Dr. Richard Jude Samulski, director of the gene therapy center at the University of North Carolina, into the clinic to treat rare neurologic diseases like Duchenne’s muscular dystrophy.
Bamboo says that Samulski was the first person to use adeno-associated viruses to replace defective genes with healthy ones; as a result, the company holds more than 20 patents in using AAV for therapeutic applications.
This looks to be a Series A, as it’s Bamboo’s only fundraise on the regulatory books. Six investors participated in the round. We’re waiting to hear back from CEO Sheila Mikhailto confirm, and learn more about the company’s use for this funding round. Bamboo did raise an undisclosed amount of funding from CureDuchenne Ventures on January 10.
The startup’s developing gene therapies for rare neurologic diseases, which include Giant axonal neuropathy (GAN), Canavan disease, Friedreich’s ataxia as well as Duchenne muscular dystrophy. Bamboo’s most advanced program is its therapeutic for GAN, which is currently in Phase 1/2 trials. CBS News ran a piece on Bamboo’s approach to GAN in October.
Just last month, Bamboo acquired a UNC’s viral vector core gene therapy manufacturing facility, Friedrich’s Ataxia News reports.
“We believe that having a leading manufacturing facility fully integrated into our business provides flexibility and a competitive advantage,” Samulski said in a release. “We anticipate rapidly moving our programs forward, including our DMD program, which is expected to enter the clinic in early 2017.”
Reversal of epigenetic promoter silencing in Friedreich ataxia by a class I histone deacetylase inhibitor
Friedreich ataxia, the most prevalent inherited ataxia, is caused by an expanded GAA triplet-repeat sequence in intron 1 of the FXN gene. Repressive chromatin spreads from the expanded GAA triplet-repeat sequence to cause epigenetic silencing of the FXN promoter via altered nucleosomal positioning and reduced chromatin accessibility. Indeed, deficient transcriptional initiation is the predominant cause of transcriptional deficiency in Friedreich ataxia. Treatment with 109, a class I histone deacetylase (HDAC) inhibitor, resulted in increased level of FXNtranscript both upstream and downstream of the expanded GAA triplet-repeat sequence, without any change in transcript stability, suggesting that it acts via improvement of transcriptional initiation. Quantitative analysis of transcriptional initiation via metabolic labeling of nascent transcripts in patient-derived cells revealed a >3-fold increase (P < 0.05) in FXN promoter function. A concomitant 3-fold improvement (P < 0.001) in FXN promoter structure and chromatin accessibility was observed via Nucleosome Occupancy and Methylome Sequencing, a high-resolution in vivo footprint assay for detecting nucleosome occupancy in individual chromatin fibers. No such improvement in FXN promoter function or structure was observed upon treatment with a chemically-related inactive compound (966). Thus epigenetic promoter silencing in Friedreich ataxia is reversible, and the results implicate class I HDACs in repeat-mediated promoter silencing.
Moving beyond DNA: A brief history of epigenetics
Like many principles in science, epigenetics started with the recognition of an inexplicable phenomenon – that is, how are traits propagated between generations? The first seeds of epigenetics were arguably planted by Charles Darwin, the 19th century biologist and father of evolutionary theory. Darwin argued for a mechanism of heredity termed . In this model, indeterminate molecules referred to as “gemmules” were released from cells and transported via the bloodstream to one’s germ cells. These proposed hereditary units were thought to possess plasticity in the sense that different kinds of gemmules would be produced depending on environmental conditions. Darwin’s idea formalized a notion, often misattributed to Jean-Baptiste Lamarck, that organism’s can pass on traits that develop as a product of their lifestyle. (The origin of this concept – “” – is beyond the scope of this review). A commonly cited example is that of the humble giraffe. Since giraffes extend their necks up to high trees in search for food, Lamarck proposed that successive generations which reached for higher and higher trees would pass on increasingly elaborate necks.
A Lamarckian idea that the act of stretching one’s neck could lead to change in phenotype across generations.
Until the mid-twentieth century, it remained unclear how the fertilized egg develops into a fully functional human with processes compartmentalized into distinct organs. However, it was known that, in general, all cells in the body contained the same genome. That is to say, the sequence of A’s, T’s, C’s, and G’s were no different in one’s neurons than in one’s muscles. The question was: A shed light on this mystery.
Although cells throughout the human body have identical DNA, they may have very different form and function between types. This is due to differences in epigenetics.
By transplanting nuclei from xenopus (frog) somatic cells into empty egg cells, Nobel Laureate paved the way for our understanding of how cell types are determined. This work definitively demonstrated the plasticity of cell identity. The embryos developed into adult frogs that were fertile and able to reproduce. Thus, the full set of processes necessary for embryogenesis were recapitulated in the egg cell that received the transplanted nucleus. Given the supposed genetic homogeneity of these cells, it was clear that some other factor within the nucleus was at play.
The term epigenetics is literally translated as being above or upon genetics, which is befitting given that it is an extra layer of biological information overlaid on the genome. In practice, epigenetics is defined as changes to DNA excluding those which alter the actual nucleotide sequence. However, a great irony arose in 1953 when the double-helical structure of DNA was elucidated by ; The composition of DNA was characterized well after its chemical modifications (epigenetics) were. Indeed, and as outlined by Edgar Stedman preceded the DNA structure by 3 years. Histones were documented as far back as 1884 by .
coined the term, “epigenetic lasndscape” and is thought of by many to be the father of epigenetics. Waddington’s landscape concept was a pivotal concept in developmental biology as it attempted to explain how a static set of DNA sequences could dynamically give rise to a complex organism. Pioneering work by Waddington also demonstrated compelling evidence for inheritance of a seemingly .
Modern day epigenetics is comprised of methylation, histones and their modifications, and non-coding RNAs. Acting in concert, these features coordinate intricate regulatory mechanisms that tightly control the expression of the genome. The propensity of the environment for perturbing these epigenetic pathways has become increasingly evident. Contemporary scientists are therefore taking a fresh look at Lamarckian inheritance with the idea that epigenetics may be a .
A tangible example of methylation is the inactivation of the second X chromosome in females which is systematically “shut down” during development. It wasn’t until 1975 that a mechanistic understanding of methylation began to take shape. In that year, using the X chromosome as an extreme example of epigenetic repression, proposed a silencing role for methylation which functioned to prevent the binding of proteins involved in gene regulation. This paradigm has since been refined, and already ten years later made it known that methyl groups tend to preferentially inhabit CpG islands.
Histones and Histone Modification
Chromatin are the complex coiled structures formed through the interaction of DNA with associated histone proteins. These histones can undergo modification via acetylation, citrullination, methylation and phosphorylation of their amino residues. It is commonly accepted that loosening or tightening of the chromatin into euchromatin and heterochromatin respectively serves to modulate gene expression. This became clear with a landmark paper in 1964 by that tied chromatin modifications to transcriptional regulation.
The term non-coding RNA and all of its subclasses refers to RNA that does not encode proteins. Unlike methylation, non-coding RNA is not a direct modification of DNA however, it merits falling under the category of epigenetics because it can regulate gene expression in the absence of a changing DNA sequence. RNA interference, a prominent subgroup of RNA interaction, was discovered by in 1998. They reasoned that these interfering RNAs could bind to messenger RNAs and neutralize them, thereby preventing translation into protein. To this day continue to be discovered with (lincRNA) having only been discovered at the turn of the century.
The ability of the environment to establish epigenetic annotations has been extensively documented in recent years. In parallel, Lamarckian ideas have undergone a revival with a greater focus on . As an illustrative example from 2014, and predispose children to full-blown diabetes. This represents a clear link between lifestyle-induced non-genetic changes that end up reaching the offspring and dictating their health in a measurable way.
Epigenetics has been implicated in the pathogenesis of diseases as diverse as cancer, neurodevelopmental disorders, autism, and fragile X. Once the role of epigenetics in normal biological processes became established, groups around the world began exploring its contribution to the etiology of disease. , for example, has exploded with the recognition that methylation of promoter regions has a silencing effect on tumor suppressor genes which normally function to protect cells from turning cancerous. In 1983, set the field ablaze when they began comparing the methylation profiles of known cancer genes between normal and malignant human tissue. In the case of cancer, these epigenetic changes are thought to arise within the lifespan of an organism. However, in other diseases, like Angelman syndrome, the abnormal epigenetic pattern is established before the child is born. Such a disorder is referred to as an imprinting disorder because the methylation occurs in the parents’ gametes and are passed on to their offspring. Angelman syndrome and the related Prader-Willi syndrome were the first disorders discovered to have an imprinting defect. It wasn’t until decades after the syndromes were first observed clinically that the associated chromosome 15 abnormalities were uncovered. Today, is an active area of research which has yielded surprising results. Thus far one thing is clear:
Epigenetics has had a storied past in the scientific community, but its utility in the clinical realm is becoming ever more apparent. One disease application that looks particularly promising is that of male infertility diagnosis. Current male fertility tests are limited in the scope of parameters they can test leaving many cases of sub-fertility unexplained. There also exists an imbalance between the number of tests available for females versus males despite the fact that male factors comprise up to 50% of the couples infertility.Interestingly, a recent paper has suggested that there are. Therefore, male infertility testing represents an important unmet clinical need.
Targeted RNA or BDNF gene transfer protects against frataxin deficiency
Gene transfer of brain derived neurotrophic factor (BDNF) prevents neurodegeneration triggered by frataxin deficiency
1. 1.Centro de Biología Molecular Severo Ochoa (UAM-CSIC) and Departamento de Biología Molecular. Universidad Autónoma de Madrid (UAM), 28049, Madrid, Spain.
2. 2.Instituto de Investigaciones Sanitarias Hospital Puerta de Hierro-Majadahonda (IDIPHIM), 28222, Madrid, Spain
Correspondence: Javier Díaz-Nido, Centro de Biología Molecular Severo Ochoa. Universidad Autónoma de Madrid (UAM). Spain Telephone: +34 91 196 4562 E-mail: firstname.lastname@example.org
Present address: Hospital Infantil de México “Federico Gómez”, 06720, México, D.F., México.
The work was done: Madrid, Spain.
Received 11 September 2015; Accepted 21 January 2016