Thanks walldiver. I already referred the person that asked me these question to your post.
"<<What are Provenge's TTP results? Where were they published?>>
9901 = 0.052 published in JCO July 2006
9902A ~ 0.70 from FDA briefing docs"
As I recall, at the panel meeting the reviewer put the p value for TTP of 9901 at about 0.8 and did not make any mention of the 0.052 obtained by DNDN after adjusting appropriately for the various factors. To me, and as I recall to you, that was a travesty especially that the DNDN team did not seem to object!
"<<Provenge's effect on PSA doubling time?>>
Delays it, I believe significantly, but PSADT was not the primary endpoint of P-11 trial."
I looked it up and it seems that the increase in PSADT was about 35% at 90 days with a p value of 0.046. Also, when adjusting for testosterone recovery followingh hormone therapy, this number got better and showed a 49% increase in PSADT with a p value of 0.038.
"<<Which trial showed the Provenge 300% three year survival advantage?>>
9901, but the survival advantage vs control was only a triple, therefore it was only a 200% advantage (34% alive vs 11% alive)"
I seem to recall that 9902a also showed this 3 fold advantage in survival at 3 years but I do not recall the exact figures here.
"Provenge approval is not a slam dunk, and you know it. We had a 13-4 efficacy vote go in our favor, and it was still turned down. CBER is probably the weakest division politically inside the FDA. Who's to say it won't cave again, even if DNDN files on 9902B interim results with a p value between 0.01 and 0.05? Pressure needs to be applied on the FDA by the advocacy groups prior to the decision, even if the p value is better than 0.01."
We are mostly in agreement you and I on this issue. I was simply transferring the question that was posed to me in a PM on the IV board. None of us are sure what the politics at the FDA is really like and how powerful are the ennemies of Provenge, so anything could happen if 9902b missess its stringent interim endpoint. Even if it does not, the FDA could always find some side reason to delay approval (manufacturing and what have you...) if they really wanted to, so I think the pressure of the advocacy groups is definitely a must if Provenge is to have a fair hearing at the FDA...
