steveporsche, The FDA quote you refer to was in response to ALTH's primary basis for approval using a non-specified cox regression model to retro-fit a non-stat sig log rank breast cancer subgroup. DNDN is NOT looking at subgroups in 9901 since the entire ITT population showed a stat sig survival of 4.5 months, with nearly 12 months stat sig survival advantage in Prostate Cancer specific cause of death. The question of whether 9902a is supportive will not not rely on sub-groups, and their stat sig survival of 3 months using pre-specified cox covariates may convince the FDA - remember all they have to do is convince the FDA that this trial is supportive.
As you recall, the FDA did NOT like ALTH's use of the sub-group analysis. I have posted a more complete section of FDA text than what was shown in your post.
<<When these [breast cancer subgroup] results were analyzed using the log-rank test, no statistically significant difference in overall survival was observed between treatment arms. After study completion, a statistically significant difference was observed in the subgroup of breast cancer patients. However, this was a subgroup established for stratification purposes, not as a prespecified endpoint to test survival as a hypothesis in this specific subgroup. The finding in the breast subpopulation can only be considered exploratory at this time. Table 24 reveals the exploratory survival analysis in the subgroup of patients with primary breast cancer. The International Conference on Harmonisation – Guideline for Industry, section 11.4.2.8 (Examination of Subgroups), states that subgroup analyses “are not intended to ‘salvage’ an otherwise nonsupportive study but may suggest hypotheses worth examining in other studies or be helpful in refining labeling information, patient selection, or dose escalation.>>
Good Luck to all DNDN Longs,
BTB
