Sarah J Tabrizi
BSc (Hons) MBChB (Hons) FRCP PhD FMedSci
Professor of Clinical Neurology
This site aims to bring together information about our research projects in Huntington’s disease (HD) for patients, family members and health professionals.
Through the Huntington’s Disease Multidisciplinary Clinic of the National Hospital for Neurology and Neurosurgery, we offer expert care and involvement in cutting-edge research, including clinical trials and work to understand HD and develop new treatments.
Our group is the largest and most productive clinically-focused HD research group in the UK.
We are delighted to accept donations to support our research, to help us understand and treat Huntington’s disease. Please donate via our UCL fundraising page.
Professor Sarah Tabrizi, Director of UCL’s Huntington’s Disease Centre, recently gave a keynote speech at Google’s Zeitgeist event. Zeitgeist events are high-profile gatherings, attended by some of the finest global leaders and thinkers. The theme of this year’s event was ‘The Next Giant Leap’ and Professor Tabrizi’s speech focused on how research on a genetic dementia, like Huntington’s disease, may not only offer hope to those who carry the Huntington’s gene, but also unlock treatments for other more complex dementias such as Alzheimer’s disease. The event, which was attended by approximately 200 people and available to stream online, was an excellent opportunity to bring significant attention to Huntington’s disease and the research being conducted by Professor Tabrizi and the HD Centre. You can watch Sarah’s inspirational speech on Zeitgeist Minds, here – https://www.zeitgeistminds.com/talk/6067962410696704/sarah-tabrizi-the-human-revolution-sarah-tabrizi.
UCL today announced that a team of researchers from UCL and the University of Cambridge led by Professor Sarah Tabrizi, Director of UCL’s Huntington’s Disease Centre, have been granted a prestigious Wellcome Trust Collaborative Award in one of the largest investments in Huntington’s Disease (HD) ever given by a public funding body in the UK (see http://www.ucl.ac.uk/ion/articles/news/20160216 and www.wellcome.ac.uk/Funding/Biomedical-science/Funding-schemes/Science-collaborative-awards/index.htm). The 5-year, £3.4 million investment will support research to help our understanding of disease mechanisms in HD and, importantly, their response to treatment. This valuable work will in turn provide insights into other more common neurodegenerative diseases.
Huntington’s disease is a devastating inherited neurodegenerative condition for which there is currently no effective treatment to slow down the disease process. It is caused by a single faulty gene resulting in the build-up of a toxic protein – mutant huntingtin – which damages brain cells, leading to abnormal involuntary movements, psychiatric symptoms and dementia. In September 2015, a ground-breaking ‘gene silencing’ trial started, with Professor Tabrizi as the Global Chief Clinical Investigator working in partnership with Ionis Pharmaceuticals (http://hdresearch.ucl.ac.uk/2015/10/first-patients-treated-with-gene-silencing-drug-isis-httrx-for-huntingtons-disease-2/). The drug is an antisense oligonucleotide (ASO) and is designed to instruct neurons to make less huntingtin protein.
Many of the harmful processes which are involved in HD are also important in other more common neurodegenerative conditions such as Alzheimer’s disease. For this reason, HD provides an ideal model for general neurodegenerative mechanisms, with the potential to benefit a huge number of patients worldwide. The Wellcome Trust Collaborative Award provides a unique opportunity to link with this first human gene silencing trial in HD to understand neurodegeneration and in particular how it is modified by treatment. It builds on key collaborations with co-applicants Professor Geraint Rees at the Wellcome Trust Centre for Neuroimaging, Dr Gary Zhang (UCL Department of Computer Science and Centre for Medical Image Computing) and Professor Henrik Zetterberg (UCL and University of Gothenberg). ‘This is an exciting opportunity to link cutting edge neuroscience with the novel development of therapies in HD to better understand mechanisms of neural recovery in humans’ said Professor Rees.
Working in parallel, co-applicant Professor Gillian Bates – who will be moving to UCL in 2016 to be the co-director of the UCL HD centre – will explore alternative ASO treatments to provide the next generation of therapies for HD patients. She will use mouse models of HD to develop and test novel compounds targeting the most toxic forms of the protein. These approaches could potentially slow down the disease process.
The ultimate aim of HD research is to prevent the disease developing by treating gene carriers from the very earliest stage. The third strand of the WT award will examine young adult gene carriers, decades before expected disease onset, in order to identify the best time to intervene with therapy. The collaborative team will use brain imaging and novel cognitive tests (CANTAB and EMOTICOM), developed by co-applicants Professors Trevor Robbins and Barbara Sahakian at the University of Cambridge, to determine when the first signs of the disease can be detected.
‘For the first time we have a realistic chance of finding treatments which actually slow down the disease process. Ideally we aim to administer the most successful therapies to gene carriers years before widespread damage has occurred, with the hope that we can prevent or at least significantly delay disease onset,’ said Prof Tabrizi.
This ambitious project will be one of the first to be conducted in the newly-established Huntington’s Disease Centre, led by Professor Tabrizi and Professor Bates. This facility is well-placed at the UCL Institute of Neurology to benefit from links within UCL to the Leonard Wolfson Experimental Neurology Centre, the Wellcome Trust Centre for Neuroimaging and the Centre for Medical Imaging Computing, collaborations with the Universities of Cambridge and Iowa and support from industrial partners Ionis Pharmaceuticals, Evotec, Cambridge Cognition and IXICO plc as well as the charitable organisation, CHDI Foundation Inc.
Professor Tabrizi has strong links with the HD community and is passionate about the critical role they play in research. ‘It is an extremely exciting time to be involved in HD research and an important factor in getting to this point has been the tireless devotion of our fantastic HD families’ she said. Cath Stanley, Chief Executive of the Huntington’s Disease Association, welcomed the news saying ‘I am delighted that Professor Tabrizi has received this important award. This study will deliver much-needed insights into the mechanisms underlying Huntington’s disease. The opportunity to link with the hugely important gene silencing trial will also help our understanding of how treatment may slow disease progression which will be of great benefit to the HD community worldwide.’
We are pleased to announce recruitment is now open for HD-CSF, a major new study of cerebrospinal fluid to help understand and treat Huntington’s disease. For full details click here.
Trial of innovative drug, developed by Ionis Pharmaceuticals, aims to reduce production of the toxic protein that causes devastating brain disease
As of 21 December 2015, Isis Pharmaceuticals changed their name to Ionis Pharmaceuticals. This article has been updated reflect this name change [March 2016].
The first few patients have received doses of an experimental drug for Huntington’s disease, it was announced today.
The trial aims to test the safety of an experimental drug known as IONIS-HTTRx, discovered and developed by Ionis Pharmaceuticals. Administered by injection into spinal fluid to improve its delivery to the brain, the drug is the first tested in patients that targets the known cause of the disease: a toxic protein called mutant huntingtin which slowly damages and kills neurons, leading to the progressive and ultimately fatal decline in mental and physical abilities that is the devastating hallmark of Huntington’s disease.
The huntingtin gene and its lethal protein product have been the focus of intense research across the world since their discovery in 1993. ‘Gene silencing’ drugs, also known as ‘antisense’ drugs, are designed to reduce production of a chosen protein by attaching to the mRNA ‘message molecule’ that’s made whenever a gene is activated. IONIS-HTTRx targets the huntingtin message molecule, telling the cell to dispose of it, thereby reducing production of the mutant huntingtin protein.
There are no treatments to prevent, slow or cure Huntington’s. RNA-targeting antisense drugs, like IONIS-HTTRx, that lower huntingtin production are widely considered the most promising therapeutic strategy currently under investigation. Ionis’s Huntington’s disease therapeutics underwent over a decade of refinement and preclinical testing before human trials could begin. The first Phase 1/2a trial is focused principally on safety, using slowly increasing doses of IONIS-HTTRx with careful monitoring of patient wellbeing, scans and laboratory parameters. In addition, the researchers will be looking for chemical signs that the drug is having the desired effect – by measuring the level of mutant huntingtin protein in the cerebrospinal fluid using a newly developed assay.
The trial is set to recruit patients with very early symptoms of Huntington’s from six centres in Europe and Canada. Prof Sarah Tabrizi, director of the Huntington’s Disease Centre at University College London’s Institute of Neurology, is the global chief clinical investigator of the trial. “I’m thrilled that this antisense drug has now been safely administered to the first patients. Families ravaged by Huntington’s disease have been waiting for this milestone for decades. I look forward to ensuring the smooth running of this first trial and hopefully seeing IONIS-HTTRx through to efficacy testing and licensing,” said Prof Tabrizi.
Ionis Pharmaceuticals has partnered with Roche to develop IONIS-HTTRx to treat Huntington’s disease. C. Frank Bennett, Ph.D., senior vice president of research at Ionis Pharmaceuticals, said, “Antisense drugs have great potential for many neurodegenerative diseases because they can be tailored to modify the production of any target protein. Huntington’s is ideally suited to this innovative therapeutic technology because it comes with genetic certainty: everyone with the mutant gene will get the disease at some point. We designed IONIS-HTTRx to target the huntingtin gene and reduce the production of huntingtin protein, which is the known cause of the disease. This approach has the potential to prevent or slow the progression of this disease. If this first-in-human trial proves the drug is safe, we look forward to continuing our successful partnership with Roche to bring the drug to market.”
At UCL, the trial is hosted in the new Leonard Wolfson Experimental Neurology Centre, a custom-built centre designed to accelerate innovative treatments for neurodegenerative diseases, headed by Prof Vincenzo Libri. The administration of the first doses of IONIS-HTT-Rx marks the Centre’s first use as a phase 1 ‘first into human’ trial facility, as well as the first time that an experimental drug has been given by spinal injection in the 156-year history of the National Hospital for Neurology and Neurosurgery, part of University College London Hospitals (UCLH) NHS Foundation Trust. Crucial support for this important achievement came from a groundbreaking partnership with the Clinical Trials Pharmacy at nearby Great Ormond Street Hospital (GOSH) where the IONIS-HTT-Rx is prepared for administration. The trial also demonstrates the value of successful collaboration between NHS and academic infrastructures in the form of the National Institute for Health Research (NIHR) UCL/UCLH Biomedical Research Centre.
Cath Stanley, Chief Executive of the Huntington’s Disease Association of England and Wales, welcomed the news that the first doses of IONIS-HTTRx had been given to Huntington’s patients. “As well as being desperate for good news, the Huntington’s community is uniquely well-informed and engaged with progress in research across the world,” she said. “RNA-targeting approaches are especially exciting because they tackle the problem at its source – the production of the mutant huntingtin protein. The IONIS-HTTRx trial has been eagerly awaited for many years and we hope that the news from the trial continues to be positive.”
A new measure has been developed which can explicitly characterise compensation in Huntington’s disease (HD) gene-carriers prior to clinical diagnosis. Publishing in EBioMedicine, the research team working on the study hope that identifying patterns of compensation in preclinical HD will not only improve understanding of neural mechanisms underlying HD pathology, but also provide potential targets that can be used in the testing of HD therapeutics.
HD is a neurodegenerative disease and despite considerable neuronal loss, preclinical HD gene-carriers are able to maintain normal behavior during many motor and cognitive tasks. This suggests that some form of compensation is taking place which enables those in the early stages of the disease to function normally. However, until now, there has been no experimentally-testable model of compensation to investigate this.
The international team of scientists from the Department of Neurodegenerative Disease and the Wellcome Trust Centre for Neuroimaging, UCL Institute of Neurology, UCL Institute of Cognitive Neuroscience, Albert Ludwigs University of Freiburg, University Hospital Salpêtrière Paris, University of Leiden, University of British Columbia, University of Ulm, University of Iowa, and Monash University Melbourne and the CHDI Foundation have developed a new model which uses functional and structural Magnetic Resonance Imaging (MRI) to investigate potential compensatory associations between behaviour and brain activity in preclinical HD patients. Using variability in levels of brain atrophy to mark disease severity, the research team have shown that in those HD gene-carriers with the most significant neuronal loss there is localised compensation in the right hemisphere during cognitive processing, while comparable function in the left hemisphere appears to deteriorate.
“In demonstrating hemisphere-specific compensation in preclinical HD gene-carriers, we have provided potential targets for the future planned testing of disease modifying agents in the preclinical phases of HD where it may be important to monitor for preservation of compensatory activity.” said Prof Sarah Tabrizi of UCL Institute of Neurology.
Furthermore, as HD is caused by a single gene mutation and fully heritable, it is an ideal model for studying not only the earliest stages of HD, but neurodegeneration generally, as it possible to predict who will develop the disease many years before symptom onset.
“By using this model we can gain insight into the more common protein-misfolding neurodegenerative diseases, such as Alzheimer’s and Parkinson’s disease, which are largely sporadic and are therefore much more challenging to study in the preclinical phases.”