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Court Finds Obviousness Based on Adjacent Figures in a Single Prior Art Reference

08-1073
January 15, 2009

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Last Month at the Federal Circuit - February 2009

Judges: Lourie (author), Rader, Prost

[Appealed from: D. Del., Judge Robinson]

In Boston Scientific Scimed, Inc. v. Cordis Corp., No. 08-1073 (Fed. Cir. Jan. 15, 2009), the Federal Circuit affirmed the district court’s construction of claim 8 of U.S. Patent No. 6,120,536 (“the ’536 patent”), but reversed the district court’s denial of Cordis Corporation’s (“Cordis”) motion for JMOL, finding that claim 8 of the ’536 patent would have been obvious in view of a prior art patent showing two adjacent figures that together disclosed all the elements of that claim.

Boston Scientific Scimed, Inc. and Boston Scientific Corporation (collectively “Boston Scientific”) own the ’536 patent, which relates to drug-eluting expandable stents. The stents are coated with an undercoat that incorporates a biologically active material, and a topcoat comprising a nonthrombogenic material that provides “long term non-thrombogenicity . . . during and after release of the biologically active material.” Slip op. at 2. Cordis makes the Cypher drug-eluting expandable stent. Boston Scientific sued Cordis, alleging that the Cypher stent infringed the ’536 patent. At trial, the jury found that claim 8 of the ’536 patent would not have been obvious based on, among other prior art references, U.S. Patent No. 5,545,208 (“Wolff”). The jury also found that the Cypher stent infringed that claim.

After trial, Cordis filed a renewed motion for JMOL or, in the alternative, a new trial on infringement and validity, but the district court upheld the jury’s verdict. Cordis again moved for a new trial based on new FDA evidence of increased risk of thrombosis in patients treated with drug-eluting stents, arguing that the Cypher stent could not provide long term nonthrombogenicity. The district court denied the motion. Cordis timely appealed the district court’s claim construction, the denial of JMOL of obviousness and noninfringement, and the denial of a new trial.

On appeal, the Federal Circuit considered whether the court properly construed the phrase “nonthrombogenic material which provides long term non-thrombogenicity to the device portion during and after release of the biologically active material” to mean “a material that does not promote thrombosis for a period of time that extends both during and after release of the biologically active material.” Id. at 3. The district court had relied on medical dictionary definitions for the meaning of “thrombogenic,” which did not appear in the patent, and “thrombolytic,” which appeared in the specification but not in the claims.

The Federal Circuit agreed that the district court correctly construed the “non-thrombogenic limitation,” and that it properly employed the analysis set forth in Phillips v. AWH Corp., 415 F.3d 1303 (Fed. Cir. 2005) (en banc). Because the Federal Circuit found the meaning of “non-thrombogenic” unclear from the claims themselves, it turned to the specification, which described ways to modify a topcoat or surface to be more nonthrombogenic. Thus, the Court concluded that the thrombogenic activity of the claimed stents is reduced relative to stents whose topcoats have not been so modified. Accordingly, the Court rejected Cordis’s argument that “non-thrombogenic” should be read to require less thrombogenicity than an uncoated metal stent. The Court also found that the prosecution history indicated that if “non-thrombogenic” required reduced thrombogenicity over anything, it would be reduced over a coated stent, not a bare metal stent.

The Federal Circuit also held that the district court did not err by relying on a dictionary because “[c]ourts may of course ‘rely on dictionary definitions when construing claim terms, so long as the dictionary definition does not contradict any definition found in or ascertained by a reading of the patent documents.’” Slip op. at 9 (quoting Phillips, 415 F.3d at 1322-23). Finding that the district court’s definition accorded with the specification, prosecution history, and the dictionary definition of a related term, the Federal Circuit affirmed the district court’s definition of “non-thrombogenic.” The Federal Circuit also affirmed the district court’s construction of the “long term” aspect of the “non-thrombogenic” limitation, and did not address Cordis’s noninfringement argument based on an alternate claim construction.

Turning to validity, the Court considered Cordis’s argument that the district court erred in denying Cordis’s motion for JMOL of invalidity of the ’536 patent on the ground of obviousness over the Wolff patent alone. Figure 3B of Wolff shows a polymer stent made of a drug-eluting polymer with a barrier topcoat. Wolff also refers to the stent and topcoat as separate layers. Figure 4 of Wolff shows a metallic stent with a drug-eluting polymer coating, and the drug-eluting polymer coating is identified with the same numeral as the drug-eluting polymer stent of figure 3B. Cordis argued that it would have been obvious to combine Wolff’s figure 3B and figure 4.

Boston Scientific replied that claim 8 was not obvious because Wolff failed to recognize the additional nonthrombogenic benefits of a substantially drug-free topcoat over a topcoat that contains drugs, that Wolff only disclosed a single coating, and that nonthrombogenicity is not inherent in Wolff’s topcoats. As secondary considerations of nonobviousness, Boston Scientific pointed to the apparent failure of others to design a drug-eluting stent before the ’536 patent’s priority date. Boston Scientific also argued that Cordis’s expert admitted a long-felt need for such stents and that Cordis’s witness stated Cypher’s success was due to the claimed polymer coating system.

The Federal Circuit agreed with Cordis that Wolff alone rendered claim 8 of the ’536 patent obvious and therefore invalid. Pointing to figure 3B and the specification of the ’536 patent, the Court noted that figure 3B shows a layer made of polymer covered by a second layer of polymer. The Court further noted that the specification teaches that the stent in figure 3B may be made from one or several layers of polymer. The Court also pointed to passages of the ’536 patent showing Wolff’s contemplation of using stent design to reduce thrombogenesis, in addition to using the elution of a thrombolytic drug to reduce thrombogenesis. Finally, the Court rejected Boston Scientific’s argument that Wolff failed to recognize the additional nonthrombogenic benefits of the topcoat, explaining that Wolff need not have recognized the additional benefit of one embodiment to have rendered the claim obvious.

For these reasons, the Court concluded that Wolff teaches all of the limitations of claim 8 of the ’536 patent, and the record did not contain substantial evidence for the jury to conclude otherwise. The Court qualified this statement of fact in that all of the limitations were found in two separate embodiments pictured side by side in Wolff, not in one embodiment. However, “[c]ombining two embodiments disclosed adjacent to each other in a prior art patent does not require a leap of inventiveness.” Id. at 17. The Court concluded that one of ordinary skill would have been motivated to coat the metal stent of figure 4, including its layer of drug-containing polymer, with a second layer of polymer, like the layer depicted in figure 3B, and that the combination constitutes claim 8. The Court found the weak secondary considerations of nonobviousness did not overcome the strong prima facie case showing that Wolff renders claim 8 of the ’536 patent obvious. Therefore, the Federal Circuit concluded that the district court incorrectly upheld the jury’s nonobviousness verdict, and held as a matter of law that claim 8 would have been obvious in view of Wolff.