If you already found a medication that is working for you I don't see why to participate in this research.

I would appreciate more a research examining possible causes to SFN and treatments to the causes, than researching familiar available symptomatic treatments.
And I wonder how many of those hundreds of participants in this trial could get better treatment if instead of trying these symptomatic drugs they would get a thorough investigation for the cause of their SFN, or participate in a research with more expensive drugs as IVIG.