re "Still curious as to whether a single corporation/person/group/ institution was responsible for last week's volume spike up, since there was no published clinical or transactional news, and there were some fairly large blocks."
Just from looking at daily charts at the time it seemed there were about 200K shares blocks purchased after the opening on Fri and Mon a week ago ago at about $2 and $2.50 per share respectively. Besides that apparent $1 Million purchase by some entity the rest seemed to be a lot of daytrader noise. With daytrader distortion of volume in every hot moving stock I think total volume gets exaggerated in terms of meaning. Now who made those apparent two big buys at around $2 and $2.50 is a matter of speculation