I would definitely bet on a secondary. All they need to sell is 10M shares and they raise $2B. Keep in mind, Wall Street wants a piece of the action, and Puma needs more funds for the next few years to finance the NDA and the market launch. They'll need more than $195M for that alone if they want any margin of safety. A lot can go wrong from now until FDA approval. They also need more shares outstanding now to make the company more accessible to WS and hedgies. Right now there are too few shares to trade. This keeps people away.
My prediction: the secondary will be priced at $170 to $190/share. It will be announced within a month.