NorthWest Biotherapeutics Inc (NWBO)

[AVII77]

But is Linda Liau privy to such trial details at this point, or is she just assuming that OS is now the sole metric of interest? I realize she was the chief scientist for the early trial(s), but what is her current role?

She is the trials Principal Investigator.

But any physician participating in this trial would be privy to these details. The protocol is not secret. They must agree to it themselves and they must submit it to their hospitals IRB for their approval too. The same goes for any amendment to the protocol.

So yes, if such a change was made, Dr. Liau would know.

So far you have not refuted the possibility that they could currently be looking at PFS for early full-approval if the old bar of 6 months improvement is currently shown, based on a look at data that they may not have requested by NWBO or their DMC.

The current level of enrollment, not recruitment, is sufficient for consideration of full early approval based on the original primary metric of PFS with the original threshold for approval of 6 months improvement.

I suppose you wouldn't believe me if I just said that can't happen. (LOL, I don't blame you for wanting an explanation).

First of all, they can't stop a study for overwhelming efficacy based "on a look at data that they may not have requested by NWBO or their DMC". That would be an "unplanned interim". Now, unplanned interims can be performed (and there are valid reasons to perform them), but then going ahead and stopping (claiming efficacy) based on that unplanned interim is really problematic.

(Did you see my post in response to you about the Sutent in PNet trial that stopped early at an unplanned interim and all the haranguing took 2 years before it was approved - that was a lesson on how NOT to stop a trial).

The other issue is performing a PFS interim w/o reaching full enrollment.

Yet another issue is stopping ANY trial based on an interim. (It is well recognized that trials stopped at interims tend to over-estimate efficacy). So, if you are going to "stop", it better be pretty damn good results (meaning stat sig on OS too).


I'm a little confuse by your second sentence.

You might want to have a look at my post 3887 on the other board where I offer my calculations of what is needed for SS for PFS and OS in this trial (at the final analysis, not an interim).

In short (and see my post there for important assumptions)

To hit stat sig here on OS (after the "enhancements") with a p of 0.05 after 233 OS events would require observing an improvement of 5.3 months (beyond 17 in control).

To hit Stat Sig on the final PFS analysis (after the enhancements) with a p value of 0.02 after 248 progression events would require observing an increase of 2.5 months (beyond 7 months in control).