It’s not an entity created by law. They are advisors. They give their advice to the officers of the company. Period.
However, I doubt very much that the company is ignoring their advice. Moreover they would have no basis to know that the trial is futile or advise beyond their personal expertise and the same knowledge that the executives have today.
I believe LP mentioned them at ASCO and that they were, as a body, advising her with regard to waiting. I am not surprised. I personally would not take bulletin board advice as seriously as the SAB’s advice given their knowledge, expertise and supportive institutional connections. They were selected for very particular reasons.