9th June 2013

Major breakthrough in multiple sclerosis treatment

A phase 1 clinical trial for the first treatment to "reset" the immune system of multiple sclerosis (MS) patients has shown that the therapy is safe. It dramatically reduced patients' immune systems' reactivity to myelin by 50 to 75 percent, according to new research.

In MS, the immune system attacks and destroys myelin, the insulating layer that forms around nerves in the spinal cord, brain and optic nerve. When the insulation is destroyed, electrical signals can’t be effectively conducted, resulting in symptoms that range from mild limb numbness to paralysis or blindness.

“The therapy stops autoimmune responses that are already activated and prevents activation of new autoimmune cells,” said Stephen Miller, Professor of Microbiology-Immunology at Northwestern University. “Our approach leaves the function of the normal immune system intact. That’s the holy grail.”

Miller is co-author of a paper on the study, published this week in Science Translational Medicine. The study is a collaboration between Northwestern’s Feinberg School, University Hospital Zurich in Switzerland and University Medical Centre Hamburg-Eppendorf in Germany.

The human trial is the result of more than 30 years of preclinical research in Miller's lab. In the trial, the MS patients’ own specially processed white blood cells were used to stealthily deliver billions of myelin antigens into their bodies so their immune systems would recognise them as harmless and develop tolerance to them. Current therapies for MS suppress the entire immune system – making patients more susceptible to everyday infections and higher rates of cancer.

Although the trial’s nine patients were too few to statistically determine the treatment’s ability to prevent the progression of MS, the study did show patients who received the highest dose of white blood cells had the greatest reduction in myelin reactivity. The primary aim of this study was to demonstrate the treatment’s safety and tolerability. It confirmed that injection of 3 billion white blood cells with myelin antigens caused no adverse affects. Most importantly, it did not reactivate the patients’ disease and did not affect their healthy immunity to everyday infections.

As part of the study, researchers tested the patients’ immunity to tetanus, because all had received tetanus shots during their lifetime. One month after the treatment, their immune responses to tetanus remained strong, showing that the treatment’s immune effect was specific only to myelin.

This safety study sets the stage for a phase 2 trial, to see if the new treatment can prevent the progression of MS. Scientists are currently trying to raise $1.5 million to launch the trial, which has already been approved in Switzerland. Using a biodegradable nanoparticle filled with myelin antigen, Miller’s pre-clinical research has already shown the treatment can stop progression of MS in mice, as reported last November.

Using a patient’s white blood cells is a costly and labour-intensive procedure. Miller’s study showed the nanoparticles, which are potentially cheaper and more accessible to a general population, could be as effective as the white blood cells as delivery vehicles. Furthermore, this therapy – with further testing – may be useful in treating not only MS, but also a host of other autoimmune and allergic diseases, simply by switching the antigens.

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