This is a very low volume traded issue so anyone person that unloads more then a few thousand shares can effectively cause the price of this stock to drop by a considerable amount, but that being said you don't want to micro manage a bio tech. Only invest enough so you can afford to maintain your position long-term and hold on. Don't make the same mistake that I did with ACAD last year when I sold out 2200 shares at 1.80 after purchasing them for $1.25 only a few months prior. ACAD now trades over $27.00 per share. The same thing can happen here.
LPTN has been trading since late July with no visible means of support (almost nothing showing on the bid on a typical day), yet staying around 6, looking like arranged transactions between institutions. That apparently has stopped, and might explain the drop. Also, dilution is more likely than buy out at this point, so there's an understandable caution to accumulate. However, lots of us out here with a core position and ready to add, if and when that happens! GLTA