Injectable drug competes against oral generic drug, it is not going to be easy. Any new drug competes against effective generic drug without additional benefit will be tough today. In addition, primary care physicians are not used to Prolia type of drug. It is going to take time if it ever gets traction. Xgeva might fare better.
AMGN acquisition of Biovex is quite high risk in my opinion. It is either genius or dumb move. I'd think there are better opportunities than oncolytic virus from BioVex out there.