I was curious about Breakthrough Therapy Designation (BTD) requirements at FDA and found 2014 Guidance to Industry on FDA's website. One section related to BTD indicates "To support a breakthrough therapy designation, the preliminary clinical evidence must show that the drug may demonstrate substantial improvement over available therapy on one or more clinically significant endpoints" That is followed by a list of what can be used to demonstrate "Substantial Improvement" and one of the criteria on this list is as follows:

"The new drug reverses or inhibits disease progression, in contrast to available therapies that only provide symptomatic improvement."

Sure sounds tailor made for B-OM to me!