Sanofi-Synthelabo v. Apotex, Inc. clopidogrel bisulfate

Analysis This case presents an example where superior and unexpected results associated with a molecule (one enantiomer) conveyed patentability to the enantiomer over its previously disclosed (prior art) racemate. The case also introduces another mechanism through which patents can be defeated by demonstrating that the claimed subject matter is obvious. 

One of the requirements for obtaining a patent is that the claimed subject matter in the patent not be obvious in view of prior art (previously disclosed patents and publications). Obviousness [16] and prior art [17] are legally codified in Title 35 of the United States Code. 

A basic, or prima facie, case of obviousness, which would otherwise defeat patentability, may in turn be defeated by one or more secondary considerations [18]. One of the most commonly employed secondary considerations is a superior and unexpected result [18]. At trial, Apotex 

Apotex, in establishing its prima facie case of obviousness, first asserted the following facts  

A prior art Sanofi patent disclosed the racemate that the dextrorotatory enantiomer found in Plavix was separated from. 

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