Ann: Path Forward For Resubmission of MOXDUO NDA , page-12

re: Ann: Path Forward For Resubmission of MOX... Fortunately for QRX, morphine has been around in medicine for over 100 years and oxycodone for about 50 years.

It is conceivable that during the overlap of 50 years of time there would have been (many?) times when a patient, reacting badly to morphine, (or oxycodone), was hurriedly given the stated alternative drug.
And surely it would already have been reported if a serious and unexpected side-effect occurred by administering the two drugs within a very close time frame.

I think this time, time is on the side of MoxDuo.