cone said:
I'm gonna make a completely speculative guess that it's not specifically about coronavirus. Remdesivir might be broadly effective across RNA viruses, not just coronavirus. I don't know if orphan status can be removed after being granted, so the time to apply for this would be now while it has the attention and currently fits the requirements of an orphan disease. This opens the door to a variety of developmental advantages, including the extended exclusivity.
If I were involved in their program, I might be thinking that this is a good opportunity to gain some R&D advantages for a drug that we are going to push development on regardless. In seeing some of the movement with hydroxychloroquine, it's entirely possible that their lunch could get ate by a decades old drug that has no competitive protection. If that happens, they at least can still take advantage of a fast track designation to get the drug on the market. That can make future development in other areas a bit easier and fight off generics for longer.
I'm not involved in this program and it's just a blind speculation. Seems like a prudent corporate action for a number of reasons though.