If they were to make approval conditional on successful data from 9902b, That's Subpart H/accelerated approval. The only way they could do that is approve based upon TTP but I think that's a stretch.
They can do a full approval conditional on the completion of 9902b, then worry about what to do with it if 9902b turns out negative. This is a fine line I know, but it is an important one.
Unless otherwise indicated, this is the personal viewpoint of David Miller and not necessarily that of Biotech Stock Research, LLC