I’ve been researching since you posted about it, took a while to find information from more than one source. But it seems they likely aren’t using it due to the extreme hazards it posts to pregnant women along with a few other health hazards from the medication but the worst is unborn children. Now if you’re past child bearing age, it may be worth it to try, but also keep in mind it has a strong sedative reaction as well.

From all I was able to find (and sorry for not saving links), it seems it’s only being used currently as an extreme measure in PPMS which has reached pretty much its peak of disabling severity, or for Non-child bearers with PPMS who aren’t capable of taking other dmd medications due to side effects or allergies.

This medication is the primary reason behind the formation of the FDA. And is certainly not a safer alternative medication by any means, your doctor probably hasn’t mentioned it because the risk to benefit is far too skewed towards risk over benefit from taking it.