I'm with you Barb, on the failure thingy..I tried Avonex and Copaxone and didn't want to try another.
I have been taking LDN for many years, now and have been pretty stable since. It's not a miracle drug but has improved my quality of life immensely.
It seems to be helping my DD, who also has MS (early stages), to stay in remission, for the last 4 years. She never would take any of the DMDs.
In the meantime, I hope they come up with your magic bullet, soon.