Report: Determined Amgen sweetens its bid for Onyx Pharma

Onyx's campaign to spark a bidding war for the company may be working--at least a little bit. Bloomberg, which has been tracking the blow-by-blow through its sources, says that Amgen ($AMGN) has bumped its offer to $130 a share, up from the original $120 bid that prompted Onyx ($ONXX) to put itself on the auction block.

If accurate, Amgen's not far off the current share price for Onyx, hovering around $132 on Tuesday afternoon. But the news is likely to still be a disappointment for the bulls, who want to see the biotech--valued at around $10 billion--go for a much higher price. Bloomberg adds that the $130 offer is currently the highest bid.

In the weeks since Onyx acknowledged Amgen's bid, reporters at Bloomberg as well as Reuters have identified a few interested bidders. At one point in late July, Novartis ($NVS), Pfizer ($PFE) and AstraZeneca ($AZN)--anxious to grow a weakening sales number--were reportedly interested in a buyout, though Amgen is the only company publicly linked to an Onyx offer.

Onyx CEO Tony Coles

Onyx CEO Tony Coles has been given high marks for making the company look like a great acquisition target. Kyprolis sales have proved strong, indicating its potential as a blockbuster earner. Onyx demanded, and got, a big slice of Bayer's Stivarga sales after contending that its partner had developed a look-alike drug to Nexavar, which also continues to do well.

Don't look for any more public comments from Onyx, though. The company has hunkered down as it hopes to lure higher bids. And Amgen was staying mum today as well. 

- here's the story from Bloomberg

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