NorthWest Biotherapeutics Inc (NWBO)

[bbking2003]

I like this so much going to go ahead and post it again just for some people that just missed it! http://www.virtualtrials.com/news.cfm. 04/03/14 Northwest Bio Warns FDA May Throw Out Phase III Brain Cancer Study
The source of this article isn't reliable and obviously (from prior articles on the subject) knows little about brain tumors and FDA policy, but he does bring up an important point:

Is the endpoint of progression free survival acceptable to get approval for a brain cancer drug?

As a member of the "Jumpstarting Brain Tumor Drug Development Coalition" which is based on the National Brain Tumor Society’s Clinical Trial Endpoints Initiative, I recently had the honor of speaking with the FDA about this issue. The FDA is on our side - we all want to get effective drugs to the people who need them as quickly as possible, while maintaining safety. The bottom line is that the FDA said that although they prefer the overall survival endpoint, they would accept progression free survival as an endpoint for approval of a treatment - IF there was a significant benefit to the treatment.

This particular trial is special. You need a brain tumor surgery to get a tumor sample which is used to make a custom made vaccine to your tumor. Everyone in the trial gets the vaccine made as well as gets the standard of care. 2/3 of the patients get the vaccine and 1/3 get a placebo. When the patients in the placebo group have progression of the tumor, they are allowed to cross over into the treatment group and get the vaccine. This is the most humane way to design a randomized trial; however, it also makes it impossible to judge the treatment on the basis of overall survival. If the treatment actually works, the overall survivals of both groups would be the same - because both groups get the same treatment so you are comparing the treatment against itself- and the better it works the less chance it would get approved based on overall survival. The progression free survival endpoint is ideal in this case and is really the only endpoint possible. If they were forced to use overall survival, they couldn’t let the patients cross over, and the custom made vaccine would go to waste – sentencing the patient to an unnecessary death just to make the statistics look better.

The question became how much of an improvement is needed in progression free survival to justify approval. The FDA wouldn't give us a specific answer, but said that if it works, they will approve it. Historically, the FDA will approve a new treatment for incurable diseases if it is just a little better than existing treatments, or the same results as existing treatments with less side effects. The bar is not that high.