I was speaking to a pwMS and they told me that the company Acorda developing fampridine with Biogen has lost its patents in a court case, meaning that from 2018, generic fampridine may become available.
At present it has not got the NICE seal of approval and is not considered cost effective and so in many place you get no access.
Although there are surely a few more court battles to be had.
The price should drop and create greater access, but whilst checking this out, it seems the company has shed 20% of its staff.
So it is a business and a brutal business at that.
So it is about the bottom lin