There has been much in the news lately about how the drug AMPYRA, used to treat MS, has been shown in a phase II trial to improve walking in people with chronic stroke. From the content that I have read, I am not sure exactly how this is happening as there is no clinical data in the news articles and I havent been able to locate the original article yet.
What we do know is what the MS drug is currently used for. It is reported that Ampyra improves walking in people with demyelination, as seen in MS, by blocking the leakage of potassium from the nerve. This helps to improve nerve conduction and ultimately how effective the messages are in getting from the brain to the muscles. How this applies in stroke we can only extrapolate as the damage to nerves that you get from stroke and MS are very different, even the type of stroke that you have (haemorrhagic verses embolitic) will change the type of damage to the nerve.
In the news articles, statements have been made about how the drug improves walking speed and function on a scale called the Functional Independence Measure (FIM) verses those on a placebo medication. It is certainly interesting and we look forward to further clinical trials to see if they can improve quality of life and mobility post stroke.
To read one of the articles, click this link.