When the talking heads suggested that the Pfizer (NYSE:PFE)-Wyeth (NYSE:WYE) deal would spawn a myriad of mergers and acquisitions in the drug world, I bet you did not hear any of them mentioning Astellas and CV Therapeutics (NASDAQ:CVTX) as a possible hook-up. After all, that's a Japanese company not available on the U.S. exchanges and a drug developer with a market cap well under $1 billion.

Besides, it looks like Astellas had the idea of acquiring CV Therapeutics while Wyeth was just a twinkle in Pfizer's eye. Astellas says it offered $16 per share for CV Therapeutics last November, which the American drugmaker's board turned down. Astellas markets CV Therapeutics' heart-imaging diagnostic aid Lexiscan, but the Japanese drugmaker is more likely after its angina treatment, Ranexa.

I guess Astellas made its offer public to get shareholders to pressure the board into selling. Yeah, good luck with that. The company seems really excited that it got Ranexa approved as a front-line treatment for angina and I doubt a couple of months have caused management to change its mind.

CV Theraputics isn't in the best bargaining position, since it's still losing money. But there are plenty of companies still in the red that have drugs on the market -- Amylin Pharmaceuticals (NASDAQ:AMLN) and fellow Rule Breakers pick Elan (NYSE:ELN) come to mind -- and CV Theraputics is clearly worth more than $1 billion, given the recent expanded approval of Ranexa.

What happens from here is anyone's guess. Astellas could up its bid, or maybe it'll get in a bidding war -- perhaps with Menarini Group, CV Therapeutics' European marketing partner for Ranexa. But betting on that is just gambling, not investing. Just ask Biogen Idec (NASDAQ:BIIB) investors who bought after Carl Icahn said he was interested in buying the company.

What's clear is that CV Therapeutics is worth a lot more than the $9 and change that it started the year at -- something Rule Breakers subscribers already knew, since the drugmaker was recommended to subscribers in 2005. Increases in the stock price from here will be determined by whether Ranexa sales increase now that it's approved as a first-line treatment. Investors will get a little indication of how that's going when CV Therapeutics releases fourth-quarter earnings and guidance for 2009 in the next month or so.

Heart this extended Foolishness:

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Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. The Fool owns share in Pfizer, which is an Income Investor and Inside Value pick. Biogen is a Stock Advisor recommendation. The Fool has a disclosure policy.