In the article you cited, MedImmune (AZN) is talking about developing new drugs using the traditional BLA pathway:
After sizing up all the hurdles, MedImmune apparently came up with a sound economic rationale for taking the higher risk, higher reward route promised by value-added biobetters. And the risk will most definitely be higher… “In order to support any claim of superiority, FDA is almost certain to require Phase 3 trials”…
This is the polar opposite of what MNTA is trying to do, and hence I stand by the assertion that AZN is an unlikely FoB partner for MNTA.