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Federal Circuit Upholds a Silent Written Description

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By David G. Barker

In a precedential opinion this week, the Federal Circuit affirmed a district court judgment in favor of Novartis Pharmaceuticals, in an appeal brought by HEC Pharm challenging the written description in Novartis’s 9,187,405 patent.

Novartis markets a 0.5 mg daily-dose drug to treat a form of multiple sclerosis, and the patent at issue claims a related treatment method. The claimed method does not require a “loading dose”—a higher initial dose than the daily doses. Before the patent was filed, a loading dose was known to “get therapeutic levels up quickly.” Novartis’s patent explicitly excludes “an immediately preceding loading dose regimen.”

HEC challenged the patent’s validity arguing it lacked an adequate written description, because the patent was silent about whether a loading dose was necessary. Because the patent was silent, the inventors did not possess the invention as of the 2006 priority date of the patent.

The district court relied on expert testimony to find that the specifications of the patent and its 2006 priority application both disclosed a 0.5 mg daily dose. Despite the specifications’ silence, the district court also relied on expert testimony to find sufficient written description for excluding a loading dose: “if a loading dose were directed, the Patent would say that a loading dose should be administered initially.” The court concluded the written description was adequate because it indicated to a person of ordinary skill that “the claimed invention did not include the administration of a loading dose.”

The Federal Circuit affirmed the district court’s judgment, even though the specifications were silent about a loading dose. “To accept HEC’s argument would require us to . . . require literal description of every limitation in violation of our precedent.” The Court also held that there is no “new and heightened standard for negative claim limitations” like the excluded “loading dose regimen,” and that HEC identified no case that supports the argument that “silence alone cannot serve as a basis for a negative limitation.”

Though it apparently did not affect the outcome, the Court underscored a failure in the parties’ briefing. The parties knew, based on HEC’s argument, that the patent’s 2006 priority application was relevant to the written description analysis. Yet the parties failed “to fully explain the contents of [the 2006] application . . . leaving it to this court to independently search the 2006 priority application.” The Court analyzed the application anyway, noting the two applications “are, in all aspects relevant to this appeal, substantively similar.”

The dissent argued that “mere absence of a positive recitation” is not enough, and that “silence alone is insufficient.” Responding, the Court reiterated the expert testimony: “the dissent, like HEC, ignores that it is how a skilled artisan reads a disclosure that matters. Written description may take any form, so long as a skilled artisan would read the disclosure as describing the claimed invention.”

It is interesting that, as HEC argued, as of 2006 “no one, including the inventors, knew that a 0.5 mg/day dose would be effective.” The Court did not mention whether that argument was disputed. But the Court noted that “efficacy is not a requirement of the claims,” which distinguishes other cases dealing with “effective” limitations in the claims. Section 101’s requirement of a new and useful process was not involved in the analysis.