Opinion ID: 208729
Heading Depth: 1
Heading Rank: 5

Heading: Identification of a Lead Compound

Text: An obviousness argument based on structural similarity between claimed and prior art compounds clearly depends on a preliminary finding that one of ordinary skill in the art would have selected [the prior art compound] as a lead compound. Takeda, 492 F.3d at 1359; see also Eisai Co. Ltd. v. Dr. Reddy's Labs., Ltd., 533 F.3d 1353, 1359 (Fed.Cir.2008) (stating that post- KSR, a prima facie case of obviousness for a chemical compound still, in general, begins with the reasoned identification of a lead compound in the prior art). Teva argues that the '406 patent identifies 2-pyr EHDP as the most promising molecule for the inhibition of bone resorption. The trial court disagreed and concluded from the evidence that a person of ordinary skill in the art would not have identified 2-pyr EHDP as a lead compound for the treatment of osteoporosis. We need not reach this question because we conclude that even if 2-pyr EHDP was a lead compound, the evidence does not establish that it would have been obvious to a person of ordinary skill at the time of the invention to modify 2-pyr EHDP to create risedronate.