Replies to post #476255 on NorthWest Biotherapeutics Inc (NWBO)

[meirluc]

I stand corrected on the Ltfu

Maybe I am not understanding this correctly but are you and Ex in agreement that all of the 5 LTFU in the group of 232 Treatment patients were estimated by last Tuesday's presentation, to become 5 year survivors?

[GermanCol]

What Ex is saying:

No, it shows 25 actually lived 5 years. That is only 10.8%. To get to 13% they estimated the survival of the LTFU's, many who had been on study only a year or so before being lost.

Is not correct, so don't stand corrected.

You can't just divide the 25 by the 232. Survival at 5 years is really 13% and is calculated by small steps down in the survival curve each time a patient dies (event), according to the number of patients at risk (alive and in the trial) at each time. When there is a censor, what happens is that there is one less at risk from that moment on and that actually makes taller (worse for the survival curve) the next steps down each time a new patient dies. This is because you have a smaller number of patients at risk in the denominator to calculate it.

So specially this is absolutely false:

they estimated the survival of the LTFU's

Nobody did that to get the 13%.