Is an isolated gene a product of human ingenuity or a natural occurrence? That distinction will decide whether Myriad Genetics' patents on isolated breast cancer genes are upheld or bounced as ineligible when the Federal Circuit Court of Appeals reconsiders the IP next month, in light of the U.S. Supreme Court's ruling in Mayo v. Prometheus Laboratories.

In March, the Supreme Court vacated the Federal Circuit's endorsement of Myriad's patents and instructed the same three-judge appellate panel that first considered the case to hear it again, this time with the direction the Supreme Court offered in Mayo, in which it raised the bar for patent eligibility for naturally occurring phenomena. On Friday Myriad and the parties challenging its IP, the American Civil Liberties Union and the Public Patent Foundation, filed new briefs at the Federal Court, outlining how they believe Mayo should alter the panel's analysis of the breast cancer genes. A raft of amici, led by the Justice Department, also registered their positions on the question, which will have a potentially enormous impact on the pharmaceutical and biotech industries.

For Myriad and its lawyers at Jones Day, there's an easy answer: Hold the Mayo. (Sorry, couldn't resist.) Myriad's supplemental brief asserts that the Supreme Court ruling addressed a method patent -- specifically, a patent on a diagnostic test based on a metabolic process. Myriad's IP is, by contrast, compositional. It protects a physical thing, an isolated strand of DNA, not a process. According to Myriad's brief, that's a crucial distinction, since the tests of eligibility for the two kinds of patents are not the same.

Compositional patents, in Myriad's view, must have a name, character and use that's distinct from anything found in nature. They must also be the product of human invention. Myriad argued that the Federal Circuit has already weighed whether its breast cancer patents meet those criteria and has found that they do. "Mayo sheds no new light on the patent eligibility of the isolated DNA claims, and thus should not alter the court's prior judgment that those claims are the patent-eligible work of human inventors," the brief said. To drive home the potency of composition patents to the Federal Circuit, Myriad noted that no product patent has been ruled ineligible by an appeals court since 1952.

"This is not a patent on organic genes," said Gregory Castanias of Jones Day, who will argue for Myriad at the Federal Circuit on July 20. "We're talking about an entirely different molecule." Myriad isolated a gene that would otherwise not be found on its own in nature and brought new diagnostic utility to its invention, Castanias said. "The panel has already ruled that isolated DNA molecule claims are the product of human invention" and thus eligible for patents, he told me.

You will not be surprised to hear that Christopher Hansen of the ACLU disagrees. "I don't think anyone can seriously argue that Mayo didn't strengthen our position," he said. In their brief, the ACLU and PubPat outlined three Mayo-based arguments against the patent eligibility of isolated human genes. First, patents on genes pre-empt the use of unpatentable products of nature. According to the ACLU's interpretation, Mayo holds that a patented invention may not preclude more future invention than it reasonably justifies, and "it is clear that patents on 'isolated' DNA ... impermissibly foreclose future scientific work and innovation."

The brief also asserts that, under Mayo, Myriad's isolated human gene is not sufficiently different from naturally occurring DNA to be patent-eligible and that the Federal Circuit should not defer to the policies of the U.S. Patent and Trademark Office, which has been granting patents on genes for many years. "Isolation of DNA was a well-known technique at the time these patents were sought, and continues to be a routine, conventional preparatory step for using human genes in research and clinical practice," the ACLU brief said. "Isolating DNA merely makes visible a person's inherited genetic makeup." (For good measure, the brief mentions that isolated breast cancer genes are actually found in the human body during the process of cell division.)

Hansen pointed out that the Federal Circuit panel that reinstated Myriad's patents after they were ruled invalid by a U.S. district judge in Manhattan was sharply divided. One appellate judge said the patents were invalid, and the two who sided with Myriad offered different explanations. To prevail in the reconsideration, the ACLU and PubPat only have to change the mind of one of them.

More than a dozen amicus briefs have already been logged, but both sides told me they haven't done a final survey of who's supporting whom. Of particular note is the Justice Department's brief, which purports to be in support of neither side but actually agrees with the ACLU and PubPat that isolated genes should not be patentable.

"Patent protection is not available to those who simply discover existing aspects of nature, even if the discovery requires arduous work, represents keen scientific insight, and is of great value to society," the brief said. "Mayo underscores this fundamental limitation on patent protection." As in the earlier round at the Federal Circuit, both sides asked for the Justice Department's support, and the DOJ sided with Myriad's foes. Once again, the PTO did not sign the brief.

(Reporting by Alison Frankel)

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