You mention drugs and ODAC so this doesn't apply but I remember a case with a medical device for depression (Medtronics) that received a positive recommendation and then was given a non-approvable (I believe). One of the most entertaining conference calls followed where the then CEO berated the FDA (he has since been forced to resign). I believe the device was later approved despite the non-approvable.
Yep - I believe that was under Witten as well. But I haven't researched it because I thought it would be easier to find some drug (for which I understand the regulatory landscape better) which had the same thing happen. So far it has been a tough row to hoe - I haven't found one.