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Israeli scientists identify: Genes that affect responses of multiple sclerosis patients to copaxone

Contact: Yivsam Azgad
news@weizmann.ac.il
972-893-43856
Weizmann Institute of Science

A group of Israeli scientists from the Technion – Israel Institute of Technology, the Weizmann Institute of Science and Teva Pharmaceutical Industries have recently identified genes responsible for the positive response of many multiple sclerosis patients to the drug Copaxone®. These findings may contribute to the development of personalized medicine for multiple sclerosis sufferers.

Copaxone® was the first original Israeli drug to be approved by the U.S. Food and Drug Administration (FDA), and is today marketed in over 40 countries worldwide, including the U.S.A., Europe, Australia, Latin America and Israel.

The drug molecule was the fruit of research by Prof. Michael Sela, Prof. Ruth Arnon and Dr. Dvora Teitelbaum of the Weizmann Institute’s Immunology Department. It was developed for the treatment of multiple sclerosis (MS) by Teva, which produces and markets Copaxone® today.

‘Until now, medical treatments for all kinds of diseases have relied on trial and error methods to determine dosage and treatment protocols,’ says Prof. Ariel Miller of the Ruth and Bruce Rappaport Faculty of Medicine at the Technion, and Head of the Multiple Sclerosis and Brain Research Center, Carmel Medical Center, Haifa. ‘But the process of fixing the correct dosage affects the efficacy of the treatment and can lead to complications in some cases.’ In the past few years, it has been shown that many drugs are not equally effective for every patient, and this variability is due, at least in part, to genetic differences. Finding medications and doses to suit the genetic make-up of each individual patient is likely to be more successful and to cause fewer side effects.

The new research, which deals with the genetic components of the response to Copaxone®, was recently published in the journal Pharmacogenetics and Genomics. It represents a significant step toward realizing this medical vision. In the collaborative study, Teva supplied DNA samples from drug-treated patients, and the genetic tests were performed at the Crown Human Genome Center of the Weizmann Institute, headed by Prof. Doron Lancet of the Institute’s Department of Molecular Genetics. The scientists used state-of-the-art equipment – the first of its kind in Israel –which allows for the rapid and accurate scanning of variations in the human genome. The scientists then examined the links between the genetic markers they found and the response of MS patients to Copaxone®. They identified several genes that are tied to a positive response to the drug. ‘We analyzed the DNA sequences in 27 candidate genes from each patient participating in the trial,’ said Lancet, ‘and we identified two genes with a high potential for determining the response to Copaxone®. In the future, it may be possible to use this method to scan the genome of MS sufferers, to predict the response levels in advance, and to optimize the dosage and treatment protocol to suit each patient personally.’

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Also participating in the research were Prof. Jacques Beckmann (formerly at the Weizmann Institute); Drs. Liat Hayardeny and Dan Goldstaub of Teva; and Iris Grossman, a joint research student at the Technion and the Weizmann Institute.

Copaxone® – Interface between Past and Future

In the 1950’s, Prof. Efraim Katzir of the Weizmann Institute of Science, later fourth president of the State of Israel, commenced research on the properties of proteins – the building blocks of all biological systems. This research led to the design of simple synthetic models of proteins, called ‘polyamino acids.’ His research student at the time, Prof. Michael Sela (who later became President of the Weizmann Institute and was the recipient of, among many honors, the Israel Prize), decided to test the influence of these synthetic molecules on the immune system. This research led him to the conclusion that it might be possible to use these synthetic substances to curb symptoms of multiple sclerosis – an autoimmune disease in which the body’s immune system attacks proteins in the fatty layer surrounding nerve fibers, preventing the conductance of electrical signals through them. Sela, together with his student at the time, Prof. Ruth Arnon (recipient of the Israel Prize and past Vice President of the Weizmann Institute and Vice President of the Association of Academies of Sciences in Asia), and Dr. Dvora Teitelbaum, conducted a long series of experiments. These experiments eventually led to the development of Copaxone®, and clinical trials carried out by Teva showed its efficacy in treating MS. At the end of the process, in 1996, Copaxone® became the first original Israeli drug to be approved by the FDA. Today, following ten years of active sales in the U.S. and 40 countries around the world, Copaxone® has made a significant contribution to the Israeli economy.

Prof. Doron Lancet’s research is supported by the Nella and Leon Benoziyo Center for Neurological Diseases; the Crown Human Genome Center; and the Laub Fund for Oncogene Research. Prof. Lancet is the incumbent of the Ralph and Lois Silver Professorial Chair in Human Genomics.

The Weizmann Institute of Science in Rehovot, Israel, is one of the world’s top-ranking multidisciplinary research institutions. Noted for its wide-ranging exploration of the natural and exact sciences, the Institute is home to 2,600 scientists, students, technicians and supporting staff. Institute research efforts include the search for new ways of fighting disease and hunger, examining leading questions in mathematics and computer science, probing the physics of matter and the universe, creating novel materials and developing new strategies for protecting the environment.

Weizmann Institute news releases are posted on the World Wide Web at http://wis-wander.weizmann.ac.il.

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October 10, 2007 Posted by | FMS Global News, Global Health Vision, Global News, MS, Multiple Sclerosis, News, News Israel | 5 Comments

Antibody leads to repair of myelin sheath in lab study of multiple sclerosis and related disorders

Contact: Amelyn Reyes
newsbureau@mayo.edu
507-284-5005
Mayo Clinic

ROCHESTER, Minn. — Mayo Clinic researchers have found that a human antibody administered in a single low dose in laboratory mouse models can repair myelin, the insulating covering of nerves that when damaged can lead to multiple sclerosis and other disorders of the central nervous system.

The study will be presented on Oct. 9 at the American Neurological Association meeting in Washington, D.C.

“The repair of chronic spinal cord injury is seldom modeled in laboratory studies, but it is an important reality for the treatment of humans. The concept of using natural human antibodies to treat disease of this kind has not yet been tested in humans, but these research findings are very promising,” says Moses Rodriguez, M.D., a Mayo Clinic neurologist and the study’s corresponding author. “The findings could eventually lead to new treatments that could limit permanent disability,” states Arthur Warrington, Ph.D., a Mayo Clinic scientist and study author.

Myelin repair normally occurs spontaneously, but in multiple sclerosis and other disorders of the central nervous system, the myelin repair process occurs very slowly or fails altogether. Researchers are trying to determine how to speed up the myelin healing process, which they hope will eventually lead to new treatments for patients.

The antibody, which was genetically engineered from a single cell, binds to myelin and the surface of cells in the brain and spinal cord, then it triggers the cells to begin the repair process called remyelination. This antibody is the first known reagent designed to induce repair by acting within the central nervous system at the damage sites on cells responsible for myelin synthesis.

The study uses laboratory mouse models of chronic progressive multiple sclerosis in humans. The severity of the disease and also success of the treatment were largely defined by how naturally active the mice were, particularly during the night because mice are nocturnal and are especially active at this time. They received a single dose of the antibody. A minimum of 25 mcg/kg was needed to trigger remyelination, which is equivalent to about 2 mg in the average adult, considered a very low dose. The myelin repair plateaued after five weeks in the mice models.

In addition, when combined with daily methylprednisolone, (an immune modulating steroid) the antibody still promotes remyelination in mouse models. This is an important fact because the first multiple sclerosis patients treated with the antibody will have been treated first with methylprednisolone.

As a naturally occurring protein of the immune system, antibodies do not appear to carry any side effects, nor are they toxic — even when administered at 4,000 times the minimal effective dose — though the concept has not yet been tested in humans, the researchers say.

In summary, this antibody:

Promotes remyelination with a single dose as low as 25 mcg/kg in mice models

The remyelination plateaus at five weeks after a single dose

Converts a model of chronic immune mediated demyelination to one that repairs with the speed of a toxin induced model of demyelination

In terms of replicating the findings in humans, the researchers have already produced the antibody through genetic engineering and conducted preliminary toxicology experiments in mice showing that 1,000 times the therapeutic dose is not toxic. The study continues to be explored in animal models and eventually, in clinical trials.

In short, the critical finding is that when combined with methylprednisolone, the antibody still effectively promotes remyelination and does not make the mice worse, Dr. Warrington states.

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About Multiple Sclerosis:

Multiple sclerosis (MS) is a chronic, potentially debilitating disease that affects the central nervous system, which is made up of the brain and spinal cord. Multiple sclerosis is widely believed to be an autoimmune disease, a condition in which the immune system attacks components of the body as if they’re foreign.

Multiple sclerosis affects an estimated 300,000 people in the United States and probably more than 1 million people around the world — including twice as many women as men. Most people experience their first signs or symptoms between ages 20 and 40.

Collaboration and Support

The study was funded by the National Institutes of Health, the National Multiple Sclerosis Society, Multiple Sclerosis Society of Canada, the Hilton Foundation and Mr. and Mrs. Eugene Applebaum.

To obtain the latest news releases from Mayo Clinic, go to http://www.mayoclinic.org/news. MayoClinic.com (www.mayoclinic.com) is available as a resource for your health stories. For more on Mayo Clinic research, go to http://www.mayo.edu.

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October 9, 2007 Posted by | Global Health Vision, Global News, Mayo Clinic, MS, Multiple Sclerosis, News, News USA, Ottawa, RSS Feed, Toronto, UK, Washington DC City Feed | 3 Comments