On Friday, Motley Fool Inside Value pick Pfizer (NYSE:PFE) announced its purchase of partner Coley Pharmaceutical (NASDAQ:COLY). It's no Biogen Idec-sized (NASDAQ:BIIB) blockbuster deal, but Pfizer's $164 million in net cash secures Coley's novel technology for targeting toll-like receptors (TLR).

Pfizer and Coley have been partners since 2005, after Pfizer paid $50 million in up-front cash for rights to a TLR cancer-fighting compound. Earlier in the year, the drugmakers hit a setback with the drug, after a data monitoring board shut down a phase 3 lung cancer study because of a lack of efficacy. Other phase 2 studies with the compound, memorably named PF-3512676, remain ongoing.

Coley has been one of the leaders on the bumpy road toward developing new TLR compounds. Several drugmakers have focused on this class of therapies, with mixed clinical trial results to date.

Coley has focused its TLR research on drugs targeting cancer and asthma, and on improving vaccines. Other drugmakers, such as Dynavax Technologies (NASDAQ:DVAX), have been working on developing compounds to target toll-like receptors for a wide range of indications, from infectious diseases to allergy treatments.

This deal for Coley will consume only a fraction of the $27 billion in cash and investments on Pfizer's balance sheet. With $9.6 billion of operating cash flow in the first nine months of the year, this deal won't have any material effect on Pfizer's ability to make any of the other, potentially much larger deals the company's reportedly considering.

Getting Coley won't do anything to solve Pfizer's near-term revenue issues, as patents for many of its top drugs expire. Coley's latest-stage asset is a vaccine adjuvant in phase 3 testing, but it's already partnered with GlaxoSmithKline (NYSE:GSK). As a result, this deal will take a long time to pay off for Pfizer, if at all.

Other drugmakers have turned similarly small acquisitions into lucrative payoffs; witness Johnson and Johnson's (NYSE:JNJ) $320 million buyout of Tibotec in 2002. Fools should watch Pfizer's R&D showcases in the years ahead, to see how much use it gets from its Coley TLR assets.

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Fool contributor Brian Lawler does not own shares of any company mentioned in this article. The Fool's disclosure policy is your friend.