NorthWest Biotherapeutics Inc (NWBO)

[DJNatan]

Hi Sent
I'm probably misreading your thoughts but PFS and OS are independent measures. Each has a hypothesis that is considered separately. Each has their own pvalue, or confidence level.

The hypothesis (PFS Exceeds or not) is written to be either is a significant change or there is not a significant change. Each is assigned the classic .05 confidence level.

"The primary objective of this study is to compare progression free survival from time of randomization between patients treated with DCVax-L and control patients."

This was not true apparently - that is to say it was not measurable in a sufficient number of people. So now the fate of the trial hangs on one primary metric, OS.

Interestingly, some researchers believe that extending PFS without bothering about extending OS is a worthy goal, which has caused some kerfuffle.
https://ascopubs.org/doi/10.1200/JCO.2011.38.7571

On the other hand, compatibility may replace confidence testing. Liau is a champ of this position, apparently, as she has voiced her interest in developing more diagnostics - the roadway to compatibility testing.

https://www.nature.com/articles/d41586-019-00857-9

Cheers