Hypothetical reason for Endo's disengagement Since BCG only got the fast track from FDA as a refractory drug because there is no available non-chemo drug on the market for the specific purpose, they have to go for the approval as a refractory drug. And yet all trials require a comparator. It has already been proven that they can't get any acceptable approved drug as a comparator. They have to abandon the refractory approach.
If they try to get the approval as a 1st line drug in the U.S. Endo and BNC will have to go through the whole application process again and still might not get the fast track designation because there is BCG that is available now. Even if they can get the fast track, it still means a long time.
Thus, it is a calculated attempt to go it alone by BNC via the Health Canada venue. It might not have as stringent a requirement to get the Notice of Compliance with condition. It also might be easier since BNC as a Canadian company might be looked at with more favorable eyes by Health Cnada. I think HC would be itching to see one of its own Canadian Biothech come up with a cancer drug that has the potential to be the drug of choice for a major cancer.
JMHO.