NorthWest Biotherapeutics Inc (NWBO)

[exwannabe]

Re: crossover and AVI11s post.

Though I agree with what he posts, some here are talking at tangents.

The FDA will accept OS from crossover data. This is easily demonstrated by the example of Provenge, approved in 2010 on a design with OS as the endpoint and crossover (to frozen product of unknown quality) allowed.

BTW, that trial was initially designed with PFS as the endpoint, then changed a couple years into the trial to use OS as the primary.

The earlier Provenge submission also had trials with crossover, but in these the primary was PFS. The PFS endpoint failed, and DNDN was trying to get approved on the OS p value being <.05 Close, but no cigar. That is my basis for saying PFS has to be stat sig (unless NWBO actually does get the primary changed to OS).

In evaluating crossover, the FDA never even looked at if it was causing the trial to look worse. All they looked at was the opposite, could the crossover have made the trial look better (by delaying docetaxel).

Anyway, AVI11's point was that they MUST look at the original randomized arms in evaluating OS, despite crossover. You can not say "Look at those who received DCVAX-l".

In that, he is clearly right.