Inter­national Linked Clinical Trials Initiative

The International Linked Clinical Trials (iLCT) initiative identifies potential new therapies for Parkinson’s disease from drugs approved to treat other conditions and that have demonstrated neuroprotective effects in preclinical experiments. By using drugs that already have passed rigorous safety and toxicology trials, iLCT aims to significantly cut the amount of time it takes for a potential treatment to move from the laboratory to clinical trials and, ultimately, to the patient. This approach also can reduce the cost of bringing new Parkinson’s disease treatments to fruition.

The expense of clinical trials seriously hampers translation from the lab to the clinic. More than 90 percent of drugs fail during development (Brundin et al 2013). Those that do pass early trials face a long road before they can be used to treat patients — it can take more than a decade and more than $1 billion to move a drug from development to the market.

This is where iLCT comes in. A program spearheaded by Parkinson’s research charity Cure Parkinson’s in collaboration with Van Andel Institute (VAI), iLCT is made up of leading Parkinson’s disease experts from around the world. Members form a committee that prioritizes promising new therapies for clinical trials in hopes of shortening the time it takes to get new treatments to patients.

Clinical Trials

The International Linked Clinical Trials committee meets in person annually to examine dozens of potential therapeutics and selects those that have the highest likelihood of successfully treating Parkinson’s disease. The drugs listed below are currently in clinical trials and have been chosen by the committee based on drug safety, the drug’s ability to pass through the blood-brain barrier, mode of action, ability to measure the drug’s effectiveness, and demonstrated success in preclinical models (Brundin et al 2013).

Ambroxol is currently approved in Europe to treat respiratory ailments. Lab studies have shown that it improves the function of a protein that plays a key role in cellular “trash removal.” Breakdowns in these processes are thought to be associated with neurodegenerative disease onset and progression.

Read more about the recently announced Phase 3 clinical trial of ambroxol here.

Simvastatin treats high cholesterol but could have applications in Parkinson’s disease due to its anti-inflammatory properties. Simvastatin’s effects in Parkinson’s are the subject of a clinical trial that is underway across 21 centers in the United Kingdom and is led by University of Plymouth.

To learn more, please visit the Cure Parkinson’s website here.

Exenatide is a type 2 diabetes drug that has shown great promise as a potential disease-modifying therapy for Parkinson’s in laboratory experiments and in clinical trials.

The most recent results come from a clinical trial conducted at University College London in the United Kingdom. It involved 60 people with Parkinson’s, half of whom received an injection of exenatide once a week and half who received a placebo for 48 weeks, in addition to their usual medications. The trial was double blind, meaning that neither the investigators nor the patients knew which group received the drug and which received the placebo. At the end of this period, the drug and placebo were stopped and the patients were monitored for 12 weeks. Throughout the trial, investigators evaluated the participants’ symptoms, particularly those that were related to movement.

People with Parkinson’s who received exenatide showed a slight improvement in their motor function, although it is not clear whether this is due to the drug affecting the disease’s underlying mechanisms or if it is temporarily alleviating symptoms.

A larger study is needed to evaluate whether exenatide actually slows disease progression. Given this, the research team urges people with Parkinson’s not to add exenatide to their treatment plans at this time.

Exenatide also appeared to be safe based on results from the trial. Some people experienced slight weight loss as well as injection site irritation, nausea and loss of appetite. However, more research is needed to definitively prove that it is safe and effective as a disease-modifying therapy in Parkinson’s. The results were in line with an earlier, smaller clinical trial in which participants also showed slight improvements in motor symptoms.

The study was led by Prof. Thomas Foltynie at University College London and was funded by The Michael J. Fox Foundation for Parkinson’s Research. It is part of the Linked Clinical Trials initiative, a program spearheaded by Cure Parkinson’s and supported in part by Van Andel Institute.

Read our blog post and FAQ here.

Liraglutide is a type 2 diabetes medication. It belongs to a class of drugs called GLP-1 agonists and prompts the release of insulin, thereby lowering glucose levels in the blood when bound to its receptor. Recent laboratory findings suggest that when liraglutide activates these receptors in the brain, the drug provides protection against degenerative damage to key brain cells, specifically those affected in Parkinson’s disease.

Trial details

Trial name: Safety and efficacy of liraglutide in Parkinson’s disease
ClinicalTrials.gov number: NCT02953665
Status: Complete
Trial location: Cedars-Sinai Medical Center (Los Angeles, California)

To read about results of this trial, please click here.

International Linked Clinical Trials Committee

International Linked Clinical Trial committee members hail from some of the leading research organizations in the world and bring with them a vast range of experience studying all facets of Parkinson’s disease. Committee members meet annually to evaluate potential treatments that may be repositioned to treat Parkinson’s disease.

Roger Barker, MBBS, MRCP, Ph.D.

Professor of Clinical Neuroscience
University of Cambridge, Cambridge, U.K.

Jerry Callahan, Ph.D., MBA

Chief Innovation Officer
Van Andel Institute, Grand Rapids, USA

Camille Carroll, M.D.

Honorary Consultant Neurologist
Plymouth Hospitals NHS Trust, U.K.

Mark R. Cookson, Ph.D.

Senior Investigator
National Institute on Aging, National Institutes of Health, Bethesda, MD

Ted Dawson, M.D., Ph.D.

Leonard and Madlyn Abramson Professor of Neurodegenerative Diseases
Johns Hopkins University, Baltimore, USA

David Devos, Ph.D.

Professor of Medical Pharmacology
University of Lille Nord de France, Lille, France

Howard Federoff, M.D., Ph.D.

Executive Vice President for Health Sciences
Executive Dean, School of Medicine
Georgetown University, Washington, D.C., USA

Brian Fiske, Ph.D.

Vice President, Research Programs
The Michael J. Fox Foundation for Parkinson’s Research
New York, New York

Tim Greenamyre, M.D., Ph.D.

Professor & Vice-Chair of Neurology, Movement Disorders Division Director
Pittsburgh Institute for Neurodegenerative Diseases, Pittsburgh, USA

Karl Kieburtz, M.D., MPH

Robert J. Joynt Professor in Neurology
Director of Clinical and Translational Science Institute, University of Rochester Medical Center
University of Rochester, Rochester, USA

Dimitri Krainc, M.D.

Chair, Department of Neurology
Director, Center for Rare Neurological Diseases
Aaron Montgomery Ward Professor
Northwestern University Feinberg School of Medicine, Chicago, USA

Andrew Lees, M.D., F.R.C.P., FMedSci

Professor of Neurology, The National Hospital for Neurology and Neurosurgery, Queen’s Square
Emeritus Director, Reta Lila Weston Institute of Neurological Sciences, University College London Institute of Neurology
University College London, U.K.

Mark Mattson, Ph.D.

Senior Investigator
Chief, Laboratory of Neurosciences
Chief, Cellular and Molecular Sciences Section
Director of the Molecular Neurobiology Lab, Massachusetts General Institute for Neurodegenerative Disease
National Institute on Aging, Balitmore, USA

Darren Moore, Ph.D.

Professor and Chair, Department of Neurodegenerative Science
Van Andel Institute, Grand Rapids, USA

Michael Schwarzschild, M.D., Ph.D.

Professor of Neurology, Harvard Medical School
Director of the Molecular Neurobiology Lab, Massachusetts General Institute for Neurodegenerative Disease
Massachusetts General Hospital and Harvard University, Boston, USA

David Simon, M.D., Ph.D.

Director, Parkinson’s Disease and Movement Disorders and the National Parkinson Foundation Center for Excellence, Beth Israel Deaconess Medical Center
Associate Professor of Neurology, Harvard Medical School, Boston, USA

Simon Stott, Ph.D.

Deputy Director of Research
Cure Parkinson’s, UK

David Sulzer, Ph.D.

Departments of Psychiatry, Pharmacology, and Neurology
Columbia University Medical Center, New York, USA

Caroline Tanner, M.D., Ph.D., F.A.A.N.

Director, Parkinson’s Disease Research Education and Clinical Center, San Francisco Veterans Affairs Medical Center
Professor of Neurology, University of California, San Francisco, USA

John Trojanowski, M.D.

William Maul Measey-Truman G. Schnabel Professor of Geriatric Medicine and Gerontology
University of Pennsylvania, Philadelphia, USA

Richard Wyse, M.D.

Director of Research and Development
Cure Parkinson’s, UK

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Aviles-Olmos I, Dickson J, Kefalopoulou Z, Djamshidian A, Kahan J, Ell P, Whitton P, Wyse R, Isaacs T, Lees A, Limousin P, Foltynie T. 2014. Motor and cognitive advantages persist 12 months after exendatide exposure in Parkinson’s diseaseJ Parkinson’s Dis 4(3):337–344.   

McNeill A, Magalhaes J, Shen C, Chau KY, Hughes D, Mehta A, Foltynie T, Cooper MJ, Abramov AY, Gegg M, Schapira AHV. 2014. Ambroxol improves lysosomal biochemistry in glucocerebrosidase mutation-linked Parkinson disease cellsBrain 137(5):1481–1495.

Brundin P, Barker R, Conn PJ, Dawson TM, Kieburtz K, Lees AJ, Schwarzschild M, Tanner CM, Isaacs T, Duffen J, Matthews H, Wyse RKH. 2013. Linked Clinical Trials—The development of new clinical learning studies in Parkinson’s disease using screening of multiple prospective new treatmentsJ Parkinson’s Dis 3:231-239.

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