the company has stated for a long time now that they think FOBs will require some clinical trials at first - nothing new there
with better characterization what mnta hopes to bring to the table is the need for smaller trials and therefore faster time to approval, higher likelihood of approval, higher probability for a label across indications, and higher probability for substitutability. Presumably once there is more experience with FOBs down the road the possibility for eliminating efficacy trial exists, and the law leaves this open to the FDA's discretion, but mnta has always stated that in the early going this is not likely