Yesterday, MGI Pharma (NASDAQ:MOGN) became the latest in a growing list of drugmakers looking for someone to acquire them.

MGI may be a relatively more attractive takeover target than some other drugmakers that have put themselves on the block lately, because its two lead drugs are unpartnered in the United States. Its lead pipeline candidate, a sedative agent named Aquavan, is also unpartnered.

MGI's top drug, Aloxi, competes with genericized drugs in the market to treat chemotherapy-related side effects. It also has Dacogen, which the FDA approved in 2006 to treat patients with myelodysplastic syndromes -- a failure of blood cells to develop correctly.

Now that MGI's biggest Dacogen competitor has been acquired by a deep-pocketed rival, one drugmaker we can rule out of any potential bidding is Celgene (NASDAQ:CELG), following its acquisition of Pharmion (NASDAQ:PHRM) last week.

Interestingly enough, with a $2.8 billion market capitalization, MGI is trading at barely less than the $2.9 billion that Celgene paid for Pharmion. So is MGI with Aloxi and Dacogen a better deal than Pharmion, with its Vidaza and European rights to Thalomid? It's hard to say, but the price Pharmion sold for probably did play a part in MGI's decision to look for an acquirer.

It's always amusing to watch shares of a drug developer soar after it declares that it's exploring "strategic alternatives." At least as often -- actually, probably more often -- the company making the announcement doesn't find an acquirer, and no deal gets consummated.

In just the past four months, it seems that half of the companies in the specialty pharma and biotech sectors have put themselves up for sale. Drugmakers such as Biogen Idec (NASDAQ:BIIB), PDL Biopharma (NASDAQ:PDLI), and QLT (NASDAQ:QLTI) are just a few of the companies in the sector publicly looking for a buyer.

The above list doesn't even include the number of drugmakers that have kept their search for an acquirer private, as is usually the case. The takeaway from this acquisition fever is that buying shares of drugmakers based on the possibility of a buyout offer can be a losing game, so it's better to invest in drug developers based on fundamentals, not the hope of a buyout that may never happen.

More Foolishness on drug company acquisitions:

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. Biogen IDEC is an active Stock Advisor pick. The Fool has an A+ disclosure policy.