You're so right - there is no cause for concern. Most are holding from the $2 - $3 range, and are sitting on fabulous returns.
A re-rating in the $4 - $5 range is a 100% return. That's fair-value for a compound entering Phase III trials.
Anything over $5 is clearly overvalued at this point. The potential revenue of this drug - given that it is even approved - is being overstated.