BSR-David,
You're missing the most important point, by far, in Scher's letter: He has drawn a line-in-the-sand demarcating the differences in the regulatory requirements betweed CDER and CBER.
I may not know anyhting about the science, but I know alot about how bureaucracies function in society and how people function withing bureacracies.
Pazdur's hand is all over this letter--Hussain's remarks in the panel meeting about how "This isn't the way we do things at ODAC"--was a harbinger of things to come. Scher's letter sets up a "turf war" within the FDA, a war that Von Eschenbach can ill afford at this point in this particular bureaucracy's history. From a strictly buraucratic/political perspective, Von E. has to come down on the conservative side and push for an "approvable" letter, a decision that can silence the critics both within and outside the FDA to a large extent. If he doesn't, then he risks reading a headline in the Washington Post/N.Y. Times (no doubt, inspired by Pazdur and Co.) that reads "Doctor on FDA panel claims FDA gives cancer patients false hope with approval of cancer vaccine." This is a risk that Von E. can't take right now with the fight in Congress ongoing.
The hope for approval rests, to a large extent, on whether and how Dr. Goodman/CBER is willing to take on Pazdur and friends. I don't know the strength of Dr. Goodman's personality, his relationship with Pazdur, his willingness to go to war with Pazdur over this or the relative strengths of CDER and CBER within the FDA or where Von E. stands in all of this.
But no matter where you stand on the question of "approval" vs. "approvable," the chances of "approval" just went down.
Bladerunner
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