DrRocker, PPHM will NOT get eventing per ARM but as a TOTAL. if they would not get it then they cannot estimate 1st/2nd look-ins and unblinding.
they actually also do NOT get patient enrolment PER arm but because randomizing is 1:1 you put one patient in CTRL, the next in Bavi, the Next in CTRL again, and so on. But far more important, they have the exact date of enrolment.
Also remember that the IDMC has TWO hats on. One as the party that monitors the trial for the FDA and in whcih capacity they can ORDER a STOP of trial for SAFETY reasons or for ETHICAL reasons (and ctrl arm must get Bavi).
The other as IDMC that advises the SPONSOR (PPHM) who can then decide if they follow the advise or not. That one includes a 'stop futility', 'continue' and 'stop efficacy' advice. They can ALSO force unblinding of a single patients when the treating Doctor would need information that is part of the blinding to treat the patients due to some evolution.
Finally it is also good to remember that the IDMC does NOT automatically provide unblinded data to PPHM when they give an advice. PPHM will have, or will have to, contract a party that will do the unblinding. This can be, but not necessarily is, the CRO. If PPHM would follow an advice and STOP then they can call for unblinding. This allows them to continue the trial if they decide not to follow the IDMC advice.