Pfizer (NYSE: PFE) obviously likes what it sees in the RNA targeted therapies offered by Denmark's Santaris Pharma. The two companies, which were already in a pact, announced yesterday that Pfizer is signing up for an additional10 drug candidates from Santaris.

Pfizer didn't make the original pact -- it was inherited when it bought Wyeth -- but the drugs from the first pact are far enough along that Pfizer seems to feel Wyeth made a good choice. Pfizer remains in good company; Santaris also has pacts with miRagen Therapeutics, Shire (Nasdaq: SHPGY), GlaxoSmithKline (NYSE: GSK) and Enzon Pharmaceuticals (Nasdaq: ENZN). The drugs won't necessarily compete with each other, since Santaris' Locked Nucleic Acid (LNA) technology can be used to treat a variety of diseases.

The LNA technology lowers protein levels by inhibiting the mRNA molecules that are a precursor to proteins. Since proteins do nearly everything in a cell, the technology can treat many diseases. A drug could inhibit proteins involved in inflammation to treat rheumatoid arthritis or the proteins involved in the synthesis of cholesterol in order to lower cholesterol levels. The possibilities are nearly endless.

LNA technology is similar to Isis Pharmaceuticals' (Nasdaq: ISIS) antisense technology, but LNA uses special ends on the inhibiting molecule to try and decrease breaking down the drug in the body and increase binding the drug to the target mRNA.

The LNA technology can also be used to target miRNAs, which themselves inhibit mRNAs. By inhibiting the inhibitor, the drug can actually cause a cell to make more protein. Of course, Isis has a joint venture with Alnylam Pharmaceuticals (Nasdaq: ALNY) studying miRNAs, so it's going head to head with Santaris there, too.

For Pfizer, it's a relatively cheap pact. The company is putting up just $14 million for expanded access to Santaris' LNA technology. If the drugs work, Pfizer's on the hook for up to $600 million in milestone payments as well as royalties.

But really, who's going to complain about paying for dessert if the drugs actually work?

Two health-care companies made the Fool's top picks for 2011 list.

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Fool contributor Brian Orelli, Ph.D., doesn't own shares of any company mentioned in this article. The Fool has a disclosure policy.