RBlatch, Unfortunately, great efficacy at all 3 dose levels is one possibility I'm not realistically entertaining, as nice as that situation would be.
No matter how you slice it, an interim analysis, followed by the addition of more subjects based on that analysis, raises some red flags. It would be nice if Dr. Stoll could find a subtle way to clarify things somewhat in the weeks ahead.
A few questions I'd like answered -
1) Was an interim analysis planned for RD-2 ahead of time? If so, was it to happen automatically, or only if needed in the case of perceived ambiguity?
2) Was an interim analysis done in RD-1?
3) Was the reason for adding subjects in RD-2 to increase 'N', or to replace dropouts?