Today's NEJM article on Provenge refutes that short-attack letter you linked to that claimed that the "placebo" arm in the Provenge trial was actually harmful:
The 21.7-month median survival of patients in the placebo group compares favorably with that in control groups in other randomized trials involving similar patient populations (range, 15.5 to 21.7 months),3,5 indicating that the treatment effect cannot be attributed to a poor outcome in the placebo group.
The other striking thing about the data shown in the article was how Provenge beat placebo not just overall, but in virtually every subgroup they looked at (maybe 20 in all). Obviously not stat. sig. in the individual subgroups, but it's the sort of forest plot that reassures me that the effect is real
Peter