NorthWest Biotherapeutics Inc (NWBO)

[sentiment_stocks]

Just to clarify Sentiment Stocks as you always seem well informed. The company would then have up to date PFS data for the entire study and know relatively where the whole study is at with regard to OS?

In my opinion yes. That essentially means that they can look at the OS numbers somewhat like one would a single arm study. Since almost all of the patients end up on DCVax (90% I think?) at cross over, if these patients as a whole have reached a higher median OS month than what historical comparisons in GBM survival have shown, the higher that number grows, the more and more likely it becomes evident that it is all due to DCVax-L.

But ultimately, the endpoints were designed to compare treatment to control. And who is in what arm is probably hard to guess at.

Had the control patients never received DCVax, it might have been easier to guess at. However, given they are all on DCVax-L, how can one really know if the patient that has lived say 36 months started out as control or treatment?

The company can look at both the information arm data, as well as (and people often forget about this group) the open label Expanded Access Protocol trial patients (which numbers about 90 or so patients) - but these were all patients that had received DCVax-L closer to their diagnosis. So determining how a recurrent GBM patient might perform when receiving DCVax-L for the first time is probably more difficult.

Of course, they could look back at the P1 trials they ran with UCLA - but I think those patients numbered only 8. And unfortunately, that's a pretty low sampling.

And so for the PFS section of this P3 trial - until they unblind, they can only know the blended data on these patients. And if there was initially a diagnosis of progression based on old criteria that might have been found to not be designed to adequately read progression accurately for an immunotherapy treatment, one might consider not unblinding the trial for PFS so that changes could be made to that criteria. If they'd unblinded, they couldn't do that.

And if by that time, reaching the OS end was within just months, the primary purpose of adjudicating PFS readings might have been to rescue the portion of alpha that might otherwise have been lost if by not doing so, PFS were found to not be statistically significant.