The wild card is that the same CTGT section of CBER that handles Provenge also handles the GVAX prostate cancer Vital 1 600 patient trial vs. Taxotere, the standard of care. They may want to compare results. Vital 1 is due to report interim results almost 6 months prior to 9902b, and comparitive results could add confusion. Personally, IMO, both should be encouraged to file/refile a BLA if they reach stat significance on the interim, since it makes stat significance on the final a virtual certainty. A bureacratic FDA, however, could hold both to the requirement to better their allocated lower alpha. Both are helped immensely by subsequent docetaxel, but both seem to have a fear that by acknowledging that fact, they undercut the idealized benefits of immunotherapy. The reality is that CD4CD25FoxP3 and CD8CD28(minus) regulatory T cells can, and have, stopped cancer vaccines cold, but that Taxotere appears to use the proclivity of Tregs for rapid proliferation in response to an immune attack as their weakness to eliminate them.Vital 2 GVAX + Taxotere vs. Taxotere, which will not be fully enrolled until early 2009, though reporting interim results at the same time due to the expected 15 month interim survival in symptomataic AIPC, might have significant results in spite of a greater patient tumor volume since the combination therapy is a requirement of the ITT arm. IMO, both Provenge and GVAX should, and will, receive FDA marketing approval eventually, but the system may be rough on them at their interim survival looks. IMO, they both should be stringently analyzed and compared, but unless some real undisclosed problems surface, should be allowed conditional approval at interim unblinding until final results are in,(once each proves that it can safely and reliably produce it in commercial quantities in accordance with cGMP) if stat significance at the final look is "reasonably likely" (a statutory requirement for conditional approval). There should also be some recognition of the need for subsequent docetaxel to optimize results, if only in the labeling of each. Unfortunately, comfortable and powerful FDA bureaucrats and lofty salaries and options for corporate execs, regardless of performance, seem to make urgency politically incorrect. Unfortunately, the reality may be that the next eighteen months may be relatively uneventful in the approval process for both Provenge and GVAX. JMHO.
AI
