trials. Regarding the legal restrictions on marketing, there is talk in Congress about removing them. The question is this: what evidentiary standards are required for secondary indications, not drug approval? Dr. Woodcock felt that the FDA would be hard-pressed to accept observational studies. They simply do not provide the level of evidence needed to change the medication label. However, clearly more discussion is required about the amount of data needed and ways to increase the size of large, simple trials to support follow-on indications for a cancer drug. Dr. Cohen said that this calls for a sustained commitment to investment in the methodological infrastructure for such trials.

Dr. Martin Murphy of the CEO Roundtable on Cancer asked the panelists about opportunities to retrospectively mine previous clinical trial data to look for signals that might be useful to identify new therapeutics. Dr. Woodcock agreed that the idea was promising and said this would be important for many diseases, especially cancer.


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