The drug Ibudilast already is used in Japan to treat asthma and patients who have had strokes. And MRIs indicate it slowed the atrophy of the brain in the early stages of MS, known as relapsing or remitting.

So the question the clinic and the National Institutes of Health will be trying to answer is whether the drug could slow the second phase of MS, known as progressive. Dr. Robert Fox says it if works, it would be an important first.

“That affects about half of all MS patients of of those 10 FDA approved therapies," Fox says. "We don’t use any of them in progressive MS, so with no therapies to alter the long-term course of the disease, we really have a very big unmet need."

Fox says the study, which will involve 28 states with 250 patients followed over two years, is possible in part because of advances in MRI that can measure smaller parts of the brain, as well as new studies of the retina.

The national Multiple Sclerosis Society also is involved in the trial, as is the drug maker Medinova. Fox underscored that he has no financial stake in the drugmaker or the trials.