Buysiders say a takeout of Onyx Pharmaceuticals Inc. is inevitable even after the company rejected an unsolicited bid from Amgen Inc. late last month. They believe the final price could come at a hefty premium relative to recent mega-deals as there are likely to be multiple bidders interested in Onyx's profit-generating oncology portfolio.

With last week's reports that Roche is now targeting Alexion Pharmaceuticals Inc., some buysiders also think the M&A chatter can only provide more legs for biotech's bull run on Wall Street (see BioCentury This Week television, July 14).