RENEWING THE FIGHT AGAINST MS
Reapproved drug leads the way for new treatments - Newsday.com
Reapproved drug leads the way for new treatments
BY JAMIE TALAN
jamie.talan@newsday.com
Reapproved drug leads the way for new treatments - Newsday.com
April 3, 2007
Elizabeth West, 44, lived nine years with multiple sclerosis, and eventually the medicines she was taking lost their power to preserveher muscle strength.
Finally, in January 2005 the Westbury resident received an infusion of the blockbuster drug Tysabri, which was pulled from the market during the month after her first treatment.
Because of Tysabri, however, West said, "I literally was able to walk out of my doctor's office without my cane."
The day before her second monthly dose, Biogen and Elan Pharmaceuticals voluntarily removed Tysabri from the market after three of the 3,000 patients who had received the novel medicine developed a potentially fatal infection of the brain: progressive multifocal leukoencephalopathy.
"To me, it was a miracle drug," said West, who joined thousands of other patients in fighting for the drug's return.
After a two-year hiatus, Tysabri is back. Seeking to avoid the serious side effect, the company has added a mandatory monitoring and surveillence program. And that's fine with West, who last month picked up where she left off - except that her muscles are much weaker than two years ago.
Tysabri is seen as today's best hope for new research and treatment for multiple sclerosis, an autoimmune disease that damages the protective insulation, called myelin, surrounding fibers of the central nervous system known as axons. When the myelin covering is lost, patients can experience any number of troubling and worsening symptoms - from muscle weakness to cognitive problems and gait disturbances.
Made from an antibody
What is unique and impressive about Tysabri is that it's a monoclonal antibody, a treatment made from the specific antibody involved in the disease process. Scientists can now make targeted antibodies to treat a wide range of diseases.
Tysabri is engineered to target a molecule found on the surface of lymphocytes, immune system cells in the bloodstream. The drug prevents lymphocytes from passing through blood vessels into the brain, which happens abnormally in patients with multiple sclerosis, explained Dr. Patricia K. Coyle, director of the MS care center and acting chair of neurology at Stony Brook University Hospital.
The studies that led to Tysabri's initial federal approval in November 2004 found that patients on the drug had a 68 percent reduction in new attacks, and much less disability than those on a placebo. The U.S. Food and Drug Administration fast-tracked Tysabri for patients with relapsing and remitting multiple sclerosis, a form characterized by symptoms and remission alternating.
What's more, the drug prevented up to 90 percent of new lesions that would have formed in the brains of patients. These lesions, scientists say, are markers for cell damage. In trying to figure out how multiple sclerosis works, scientists need to understand why the lesions are present in all forms of the disease.
Lesions seen during remission
Scientists used to think the lesions disappeared when patients were in remission, but newer scanning technologies revealed only 4 percent of the lesions go away, said Dr. Lauren Krupp, professor of neurolgy and director of the pediatric MS center at Stony Brook. The next question, then, is what are they doing there?
To answer that question, Stony Brook scientists head to the magnetic resonance imaging machine, which provides a picture of the lesions - in both the brain's white matter, containing nerve fibers, and in the gray matter, the cortex. What Coyle and Krupp are showing is that 80 percent of the lesions seen on the MRI are not associated with an MS attack but are contributing to the underlying disease process.
Damage without symptoms
They now believe that the relapsing and remitting of the disease "gives patients a false impression," Coyle said. Damage to the brain continues even when symptoms are not present, she added.
Half a million people in the United States have multiple sclerosis, and scientists think immune-mediated diseases are on the rise. Krupp said she is finding evidence that environmental exposures such as certain viruses, combined with genetic factors, can increase a person's risk for the disease.
While there are many experimental drugs in the pipeline, the National Multiple Sclerosis Society recently convened its scientists to talk about the role of stem cells in repairing the brain and repopulating it with oligodendrocytes, cells essential to forming the axon's protective myelin sheath. In mice, placing the stem cells in the brain seems to repair damage, scientists say.
Breakthrough with MRI
The Stony Brook scientists have in their hands what they think could be one of the greatest discoveries of the day. Dr. Mirjana Savatic, who works at Stony Brook and Cold Spring Harbor Laboratory, has developed a method of observing stem cells in the living human brain using an MRI machine.
In the past decade it's become clear that the adult brain has discrete populations of stem cells. Krupp is collaborating with Savatic to study the MS brain, and they can actually see recruitment of the stem cells after a new lesion - suggesting that the brain is trying to somehow repair itself.
"It's pretty amazing," said Krupp.
They will follow patients over time to understand what the stem cells are doing. They can also use the technology to test the effectiveness of treatments.
MRI spectroscopy is a noninvasive scan of the brain that provides information about its chemistry. Savatic used it to identify a substance present only in stem cells and not in mature cells, including neurons, glial cells or inflammatory cells.
When Krupp asked her to run a few patients through the MRI scan, searching for stem cells, she said she didn't expect to see much. But to her surprise, Krupp said, "where there's a lesion, we saw a peak in these stem cells."
Hope on several fronts
"It's extremely exciting to see so many new things coming," said Dr. Mark Gudesblatt, a neurologist with offices in Bay Shore and Patchogue who specializes in multiple sclerosis. In addition to Tysabri, which is given by monthly intravenous infusions, Gudesblatt suspects that the first oral MS medicine will be available in a few years.
"It gives patients tremendous hope," he added.
So far, about 100 of his 2,500 MS patients have opted for Tysabri. Other medicines are injectables that have to be taken daily or weekly. "And Tysabri is incredibly effective and well tolerated," Gudesblatt said.
West said that the gap in her treatment definitely set her back. She's hoping that within a few months her nightly dreams of running will become a reality. "I'm staying positive," she said. "I look forward to the day that I may say, 'Hey, guess what? It worked.'"
THE DIFFERENT ATTACKS ON NERVE FIBERS
Multiple sclerosis affects an estimated 2.5 million people worldwide. It attacks the central nervous system - the brain, spinal cord and optic nerves. Surrounding the nerve fibers is a fatty tissue called myelin, which helps nerve fibers conduct electrical impulses. In MS, myelin is lost in multiple areas, leaving scar tissue called sclerosis. The damaged areas also are known as plaques or lesions. People with MS may have one of four clinical courses of disease, each of which may be mild, moderate or severe.
Relapsing-remitting
Flare-ups (relapses or attacks) are episodes of acute worsening of neurologic function. They are followed by partial or complete recovery periods (remissions). This form is present in 85 percent of patients when first diagnosed.
Primary-progressive
Here, the disease worsens slowly but almost continuously, without distinct relapses or remissions. There may be some periods of minor improvement, and the rate of deterioration varies. Relatively rare, it's diagnosed in about 10 percent of patients.
Secondary-progressive
An initial period of relapsing-remitting MS is followed by steady worsening, with or without occasional flare-ups, minor recoveries (remissions) or plateaus. Before drugs were introduced to combat symptoms, 50 percent of people with relapsing-remitting MS developed this form of the disease within 10 years of their initial diagnosis. Long-term data are not yet available to demonstrate if this form is significantly delayed by treatment.
Progressive-relapsing
Steadily worsening disease from the onset, with acute relapses (attacks or exacerbations), with or without recovery. In contrast with relapsing-remitting MS, the periods between relapses are characterized by continuing disease progression. Relatively rare: about 5 percent of patients.
SOURCE: National Multiple Sclerosis Society
Copyright 2007 Newsday Inc.
http://www.newsday.com/features/printedition/ny-hscov5155526apr03,0,7835806.story?coll=ny-football-headlines&track=mostemailedlink
Reapproved drug leads the way for new treatments - Newsday.com
Reapproved drug leads the way for new treatments
BY JAMIE TALAN
jamie.talan@newsday.com
Reapproved drug leads the way for new treatments - Newsday.com
April 3, 2007
Elizabeth West, 44, lived nine years with multiple sclerosis, and eventually the medicines she was taking lost their power to preserveher muscle strength.
Finally, in January 2005 the Westbury resident received an infusion of the blockbuster drug Tysabri, which was pulled from the market during the month after her first treatment.
Because of Tysabri, however, West said, "I literally was able to walk out of my doctor's office without my cane."
The day before her second monthly dose, Biogen and Elan Pharmaceuticals voluntarily removed Tysabri from the market after three of the 3,000 patients who had received the novel medicine developed a potentially fatal infection of the brain: progressive multifocal leukoencephalopathy.
"To me, it was a miracle drug," said West, who joined thousands of other patients in fighting for the drug's return.
After a two-year hiatus, Tysabri is back. Seeking to avoid the serious side effect, the company has added a mandatory monitoring and surveillence program. And that's fine with West, who last month picked up where she left off - except that her muscles are much weaker than two years ago.
Tysabri is seen as today's best hope for new research and treatment for multiple sclerosis, an autoimmune disease that damages the protective insulation, called myelin, surrounding fibers of the central nervous system known as axons. When the myelin covering is lost, patients can experience any number of troubling and worsening symptoms - from muscle weakness to cognitive problems and gait disturbances.
Made from an antibody
What is unique and impressive about Tysabri is that it's a monoclonal antibody, a treatment made from the specific antibody involved in the disease process. Scientists can now make targeted antibodies to treat a wide range of diseases.
Tysabri is engineered to target a molecule found on the surface of lymphocytes, immune system cells in the bloodstream. The drug prevents lymphocytes from passing through blood vessels into the brain, which happens abnormally in patients with multiple sclerosis, explained Dr. Patricia K. Coyle, director of the MS care center and acting chair of neurology at Stony Brook University Hospital.
The studies that led to Tysabri's initial federal approval in November 2004 found that patients on the drug had a 68 percent reduction in new attacks, and much less disability than those on a placebo. The U.S. Food and Drug Administration fast-tracked Tysabri for patients with relapsing and remitting multiple sclerosis, a form characterized by symptoms and remission alternating.
What's more, the drug prevented up to 90 percent of new lesions that would have formed in the brains of patients. These lesions, scientists say, are markers for cell damage. In trying to figure out how multiple sclerosis works, scientists need to understand why the lesions are present in all forms of the disease.
Lesions seen during remission
Scientists used to think the lesions disappeared when patients were in remission, but newer scanning technologies revealed only 4 percent of the lesions go away, said Dr. Lauren Krupp, professor of neurolgy and director of the pediatric MS center at Stony Brook. The next question, then, is what are they doing there?
To answer that question, Stony Brook scientists head to the magnetic resonance imaging machine, which provides a picture of the lesions - in both the brain's white matter, containing nerve fibers, and in the gray matter, the cortex. What Coyle and Krupp are showing is that 80 percent of the lesions seen on the MRI are not associated with an MS attack but are contributing to the underlying disease process.
Damage without symptoms
They now believe that the relapsing and remitting of the disease "gives patients a false impression," Coyle said. Damage to the brain continues even when symptoms are not present, she added.
Half a million people in the United States have multiple sclerosis, and scientists think immune-mediated diseases are on the rise. Krupp said she is finding evidence that environmental exposures such as certain viruses, combined with genetic factors, can increase a person's risk for the disease.
While there are many experimental drugs in the pipeline, the National Multiple Sclerosis Society recently convened its scientists to talk about the role of stem cells in repairing the brain and repopulating it with oligodendrocytes, cells essential to forming the axon's protective myelin sheath. In mice, placing the stem cells in the brain seems to repair damage, scientists say.
Breakthrough with MRI
The Stony Brook scientists have in their hands what they think could be one of the greatest discoveries of the day. Dr. Mirjana Savatic, who works at Stony Brook and Cold Spring Harbor Laboratory, has developed a method of observing stem cells in the living human brain using an MRI machine.
In the past decade it's become clear that the adult brain has discrete populations of stem cells. Krupp is collaborating with Savatic to study the MS brain, and they can actually see recruitment of the stem cells after a new lesion - suggesting that the brain is trying to somehow repair itself.
"It's pretty amazing," said Krupp.
They will follow patients over time to understand what the stem cells are doing. They can also use the technology to test the effectiveness of treatments.
MRI spectroscopy is a noninvasive scan of the brain that provides information about its chemistry. Savatic used it to identify a substance present only in stem cells and not in mature cells, including neurons, glial cells or inflammatory cells.
When Krupp asked her to run a few patients through the MRI scan, searching for stem cells, she said she didn't expect to see much. But to her surprise, Krupp said, "where there's a lesion, we saw a peak in these stem cells."
Hope on several fronts
"It's extremely exciting to see so many new things coming," said Dr. Mark Gudesblatt, a neurologist with offices in Bay Shore and Patchogue who specializes in multiple sclerosis. In addition to Tysabri, which is given by monthly intravenous infusions, Gudesblatt suspects that the first oral MS medicine will be available in a few years.
"It gives patients tremendous hope," he added.
So far, about 100 of his 2,500 MS patients have opted for Tysabri. Other medicines are injectables that have to be taken daily or weekly. "And Tysabri is incredibly effective and well tolerated," Gudesblatt said.
West said that the gap in her treatment definitely set her back. She's hoping that within a few months her nightly dreams of running will become a reality. "I'm staying positive," she said. "I look forward to the day that I may say, 'Hey, guess what? It worked.'"
THE DIFFERENT ATTACKS ON NERVE FIBERS
Multiple sclerosis affects an estimated 2.5 million people worldwide. It attacks the central nervous system - the brain, spinal cord and optic nerves. Surrounding the nerve fibers is a fatty tissue called myelin, which helps nerve fibers conduct electrical impulses. In MS, myelin is lost in multiple areas, leaving scar tissue called sclerosis. The damaged areas also are known as plaques or lesions. People with MS may have one of four clinical courses of disease, each of which may be mild, moderate or severe.
Relapsing-remitting
Flare-ups (relapses or attacks) are episodes of acute worsening of neurologic function. They are followed by partial or complete recovery periods (remissions). This form is present in 85 percent of patients when first diagnosed.
Primary-progressive
Here, the disease worsens slowly but almost continuously, without distinct relapses or remissions. There may be some periods of minor improvement, and the rate of deterioration varies. Relatively rare, it's diagnosed in about 10 percent of patients.
Secondary-progressive
An initial period of relapsing-remitting MS is followed by steady worsening, with or without occasional flare-ups, minor recoveries (remissions) or plateaus. Before drugs were introduced to combat symptoms, 50 percent of people with relapsing-remitting MS developed this form of the disease within 10 years of their initial diagnosis. Long-term data are not yet available to demonstrate if this form is significantly delayed by treatment.
Progressive-relapsing
Steadily worsening disease from the onset, with acute relapses (attacks or exacerbations), with or without recovery. In contrast with relapsing-remitting MS, the periods between relapses are characterized by continuing disease progression. Relatively rare: about 5 percent of patients.
SOURCE: National Multiple Sclerosis Society
Copyright 2007 Newsday Inc.
http://www.newsday.com/features/printedition/ny-hscov5155526apr03,0,7835806.story?coll=ny-football-headlines&track=mostemailedlink
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