In the video link below, the guest doctor starts talking about the status of treatments at about 6:45 and mentions that big data has been used to screen treatments to see which would likely be the most effective....then he says most of those treatments are in the preclinical or very early phases of clinical trials. Very interesting considering B is on the down slope of the curve to completion.

https://www.youtube.com/watch?v=dHyWELtn8Ac