Dendreon Corp fka DNDNQ

[iwfal]

The concern for the interim look is the large percentage (20%) of patients who enrolled in the final 18 months of the enrollment period. These patients, if still alive, will have to be censored at the time of the interim trigger in Sep/Oct 2008. If IMPACT goes like the other Phase III trials, there won't be much separation between the two arms for the first 18 months. The censored patients cloud up the p value.


Add to this that this final 20% is sicker (because of the change in protocol) than the longest enrolled group and I'd guess >30% of the deaths in the interim will be in people who are not benefitting much from the treatment.