Replies to post #544896 on NorthWest Biotherapeutics Inc (NWBO)

[hoffmann6383]

Funny, no link is provided. Please read the Final Guidance on ECAs from the FDA. Thanks LS!

[SkyLimit2022]

Full-context dated source links are helpful. Your citation includes a tiny excerpt from 2018 guidance. In isolation, it is misleading and reflects an out-dated stance. Furthermore, there have been FDA developments since on this point. Further still, we are talking about GBM and rGBM as opposed to a less lethal disease which respond to multiple other treatment options. Crossover was for advancing/recurrent disease for which there is no treatment to extend survival.

Here is a more recent document (2022) authored by current FDA leaders:

https://www.annalsofoncology.org/article/S0923-7534(22)00006-0/fulltext

Here is the full-context link for the 2018 document that you cited:

https://www.fda.gov/media/71195/download





https://jamanetwork.com/journals/jamaoncology/fullarticle/2798847

[muee88]

WRONG!

https://www.fda.gov/media/133660/download

From page 6 to 7:

Despite the limitations of externally controlled trials compared with concurrently controlled trials, strong support for effectiveness can emerge from externally controlled trials, especially when (1) the natural history of a disease is well defined, (2) the external control population is very similar to that of the treatment group, (3) concomitant treatments that affect the primary endpoint are not substantially different between the external control population and the trial population, and (4) the results provide compelling evidence of a change in the established progression of disease. Such results could include partial or complete response in a disease where spontaneous regression is not observed, or stabilization or improvement in function in a disease where progressive functional decline is well documented to occur over the duration of the treatment period in the trial. Another example of where there is strong evidence of drug effectiveness is reversal of clinical signs and symptoms following a toxic exposure or overdose after administration of a drug antidote. In all such circumstances, a detailed understanding of the full range of possible clinical outcomes, with a well-documented natural history of the disease in the absence of treatment, is essential to interpreting trial results and, therefore, drawing a conclusion about the effectiveness of the drug.