I suspect, as flagged in an earlier post this week, that the...

I suspect, as flagged in an earlier post this week, that the spike was due to the announcement made re last year's trial results, the rise in volume attributable to people who aren't familiar with the significance (or otherwise) of post hoc data..
Post hoc analysis, or data trawling, is common in the clinical trials industry. I should emphasisise that i make the following comment NOT because of my views on Prana's trial results (because the amyloid data seems to have been judged as unambiguosly positive) but I remember being told once that "post hoc analysis is the last refuge of a negative trial result."
If the result they've now publicised was hoped for, it would have been included in the initial trial results release. If you analyse at least 20 variables, the odds are you'll come up with one result that meets statistical significance (p=0.05).
I think if something else were going on, the rise would have been sustained.
IMO only, and I remain hopeful....