Lots of money on the sidelines waiting for an entry point.
People aren't stupid, they saw the move the past couple months, the institutional buying, and most recently Baker Bros loading up. And wondered whether they'd missed the ride. Rest assured, those folks are sitting on the sidelines with lots of cash waiting to get onboard. Everyone is looking for that last penny of margin, but by the time that happens, the direction will have reversed. In the case of IDRA, it'll be a slingshot higher breaking through the 52 week high, and well you'll have missed it again.
It's funny how everyone wants the best possible price, no one wants to overpay. I get that. I'm the same way with investments. And as such, I often miss out on gains. Everyone does. In the case of IDRA the writing is on the wall though, we'll be breaking through that 52 week high this month, so why quibble about a few pennies here or there on an entry point. When we're at $100 in December it won't matter if you paid $5 or $4 a share now.