I agree that $4-5 sound more like it, but I think we may see higher on a BO. It depends on the company acquiring - if someone like Amgen, I would bet higher than $4-5.
Roche paid 46.8 Billion or $95 PPS for Genentech to own full rights to Avastin, Herceptin & Rituxan - all oncology drugs. Now it is true that Genentech had a high PPS prior to the deal with an existing portfolio of ONC drugs...but for big pharma - it is cheaper to acquire a compound than develop your own. This is the way pharma is moving today...
Time will tell on this one. But a synergistic effect with an Amgen drug would mean big money. Pure speculation.