Last Month at the Federal Circuit
Last Month at the Federal Circuit

July 2011

State of the Art Could Not Fill the Gaps in Disclosure for Written Description Support Where the Specifications Indicated Unpredictability and a Lack of Knowledge in the Art


Judges:  Bryson, Gajarsa (concurring-in-part), Moore (author)
[Appealed from D. Del., Judge Robinson]

In Boston Scientific Corp. v. Johnson & Johnson, Inc., Nos. 10-1230, -1231, -1233, -1234 (Fed. Cir. June 7, 2011), the Federal Circuit affirmed the district court’s grant of SJ that the asserted claims were invalid for lack of written description under 35 U.S.C. § 112, ¶ 1.

Johnson & Johnson, Inc. (“J&J”), and Cordis Corp. (“Cordis”) own U.S. Patent Nos. 7,217,286; 7,223,286; and 7,229,473 (collectively “the 1997 patents”) and, along with Wyeth, own U.S. Patent No. 7,300,662 (“the ’662 patent”) (collectively “the patents-in-suit”).  The patents-in-suit relate to drug-eluting stents for use in treating coronary artery disease (“CAD”).  Bare metal stents, traditionally inserted in an artery to prevent collapse following angioplasty, did not adequately address restenosis (narrowing of the artery) caused by neointimal proliferation (an increase in smooth muscle cells of the artery over time in response to injury caused by angioplasty).  Attempts to prevent restenosis led researchers to test numerous oral drugs and drug-eluting stents.  Prior to 1997, orally administered rapamycin was known to inhibit restenosis in rats.  Several analogs of rapamycin were also known in the art, including everolimus, which is both a macrocyclic lactone and triene analog of rapamycin.  Cordis’s Cypher® stent, which uses rapamycin as a therapeutic agent, was the first drug-eluting stent approved by the FDA and sold in the United States.

The 1997 patents, which share a common specification, claim drug-eluting stents using either rapamycin or a macrocyclic lactone analog of rapamycin as the therapeutic agent.  The 1997 patents contain only a single reference to macrocyclic lactones under the heading “Experiments,” but the experiments disclosed therein do not use or provide a single example of a macrocyclic lactone analog.  Cordis added the phrase “macrocyclic lactone analog” in a 2006 claim amendment shortly after a competitor, Guidant, received European approval to sell a drug-eluting stent containing everolimus.

The ’662 patent was filed in 2004, but J&J, Cordis, and Wyeth (collectively “Appellants”) asserted that the claims were entitled to an effective filing date of 2001.  The ’662 patent claims drug-eluting stents using either rapamycin or a macrocyclic triene analog of rapamycin, but does not provide an example of a macrocyclic triene analog of rapamycin; rather, the only mention of a similar term in the specification is that “[r]apamycin is a macroyclic [sic] triene antibiotic.”  Slip op. at 8 (alterations in original).  The ’662 patent does not include any data on studies performed with any rapamycin analog coated stents.  And, as with the 1997 patents, Cordis added the claim language “macrocyclic triene analogs” after Guidant received its European marketing approval.

Appellees Boston Scientific Corporation and Boston Scientific Scimed, Inc. (collectively “BSC”), filed four complaints (later consolidated) against Appellants seeking DJs that the claims of the patents-in-suit are invalid.  BSC sells an everolimus-eluting stent system.  Appellants counterclaimed for infringement.  The parties filed several SJ motions in the district court, including BSC’s SJ motion of invalidity based on nonenablement, lack of adequate written description, and indefiniteness.  The district court granted SJ, finding the 1997 patents invalid for nonenablement and lack of adequate written description, and the ’662 patent invalid for lack of adequate written description without addressing enablement.

On appeal, the Federal Circuit agreed that the 1997 patents lacked an adequate written description of the claimed genus of macrocyclic lactone analogs of rapamycin.  First, the shared specification contained virtually no information regarding the macrocyclic lactone analogs of rapamycin except that the term was mentioned under the heading “Experiments.”  Not one example, however, included a use of a macrocyclic lactone analog.  And, the patents gave no guidance on how to properly determine whether a compound was a macrocyclic lactone analog, given the potentially limitless number of compounds that are structurally similar to the complex rapamycin compound.  Thus, the Federal Circuit held that “[a]n ipsis verbis disclosure of a claimed genus (under the heading Experiments) is not per se sufficient to meet the written description requirement.”  Id. at 18.


“[W]hen the four corners of the specification directly contradict information that the patentee alleges is ‘well-known’ to a person of skill at the effective filing date, no reasonable jury could conclude that the patentee possessed the invention.”  Slip op. at 23.

Second, the Court rejected Appellants’ argument that the knowledge in the art was so well known as to excuse a more detailed disclosure in the specification.  Although some species were known, Appellants’ own declarations detailed the failure of others to develop drug-eluting stents to inhibit restenosis and the unpredictability of the art.  Further, statements in the common specification indicated that the mechanism of action of rapamycin was not fully understood.  The Court stated that while a patentee may rely on information that is “well-known in the art” for purposes of meeting the written description requirement, “when the four corners of the specification directly contradict information that the patentee alleges is ‘well-known’ to a person of skill at the effective filing date, no reasonable jury could conclude that the patentee possessed the invention.”  Id. at 23.  Thus, the Court rejected Appellants’ argument that there was a known correlation between the function and structure of rapamycin and its analogs that provided additional written description support for the entire genus of macrocyclic lactone analogs.

Given the absence of information regarding the structural characteristics of macrocyclic lactone analogs or examples of macrocyclic lactone analogs in the specification, and the nascent state of using drug-eluting stents to inhibit restenosis, the Court refused to “reward an inventor’s invitation to other researchers to discover which of the thousands of macrocyclic lactone analogs of rapamycin could conceivably work in a drug-eluting stent.”  Id.  Accordingly, the Court did not separately address whether the 1997 patents were enabled.

Addressing the ’662 patent, the Federal Circuit similarly found that the claimed subgenus of “macrocyclic triene analogs” of rapamycin was not adequately described.  First, the Court noted that the specification never disclosed the subgenus itself, i.e., the specification never mentioned “macrocyclic triene analogs” of rapamycin; rather, the only disclosure was that “[r]apamycin is a macroyclic [sic] triene antibiotic.”  Id. at 24 (alterations in original).  As in Fujikawa v. Wattanasin, 93 F.3d 1559, 1570 (Fed. Cir. 1996), where a claimed subgenus was not disclosed ipsis verbis in the specification, the ’662 patent failed to indicate that the claimed triene analogs might be of special interest.  Thus, the Court found that given the nascent state of using drug-eluting stents at the time of filing, the lack of any “blaze marks” pointing to triene analogs precluded the conclusion that the analogs were adequately described.

Second, the Federal Circuit found that the functional disclosures in the ’662 patent failed to sufficiently describe the claimed subgenus of macrocyclic triene analogs or provide sufficient blaze marks as to which analogs might successfully work in drug-eluting stents.  Even as of the 2001 effective filing date of the ’662 patent, the relationship between the function of rapamycin and its structure was not so well known that it excused the patentee’s failure to explicitly disclose the claimed subgenus or any species within the subgenus.  Further, as with the 1997 patents, the ’662 patent specification confirmed that the mechanism of action of rapamycin was not well known in the art at the effective filing date, thus directly contradicting Appellants’ assertion that there was a well-known correlation between the structure of rapamycin and its function.

Finally, the Court noted that the ’662 patent contains insufficient support for the highly specific functional requirements claimed.  For example, claim 1 required “from about 64 μg to about 197 μg of rapamycin or a macrocyclic triene analog thereof . . . wherein said device provides an in-stent late loss in diameter at 12 months following implantation in a human of less than about 0.5 mm.”  Id. at 27 (alteration in original).  The ’662 patent, however, failed to include any information suggesting how a person of skill in the art would select macrocyclic triene analogs with such highly specific performance requirements or which structural features of the analogs are necessary to achieve those results.

Accordingly, the Federal Circuit affirmed the district court’s grant of SJ that the patents-in-suit were invalid for lack of an adequate written description pursuant to 35 U.S.C. § 112, ¶ 1.

Judge Gajarsa concurred-in-part because, while he agreed that the patents-in-suit were invalid, he would have based that finding for the 1997 patents on nonenablement.  According to Judge Gajarsa, the majority’s opinion “further extends the written description requirement into the realm of enablement.”  Gajarsa Concurrence at 2.  Specifically, in his view, the 1997 patents did not have to “explain how to synthesize, identify, or determine the biological activity of a suitable macrocyclic lactone analog” because scientists could hypothesize that useful analogs could be created by changing parts of the rapamycin molecule.  Id. at 3-4.  “The patents did, however, need to disclose where the rapamycin molecule should be modified to obtain a suitable analog with the desired efficacy in stents.”  Id. at 4.  Thus, “[b]ecause no one knew of any rapamycin analogs with the desired efficacy when delivered by stents as of the filing date of the 1997 patents, Appellants’ claims are not enabled.”  Id.