Last week, the Federal Circuit heard oral argument in a patent case we have been following because it attracted three amicus briefs. The case, REGENXBIO Inc. v. Sarepta Therapeutics, Inc., raises questions relating to eligibility of a genetically engineered cultured host cell that contains nucleic acid sequences from at least two different organisms spliced together into a single molecule. This case asks whether a district court erred in holding patent claims ineligible because the inventors merely “combined natural products and put them in a host cell.” Judges Dyk, Hughes, and Stoll heard the oral argument. This is our argument recap.
Susan Morrison argued for REGENXBIO. She opened by urging the court to reverse the district court’s decision based on Supreme Court precedent. She emphasized that “neither the cultured host cell nor the recombinant nucleic acid molecule previously existed in nature,” a point, she said, that Sarepta’s own experts conceded.
A judge expressed concern that REGENXBIO’s claims were “incredibly broad,” suggesting they covered “all sorts of possible uses of the rh.10 vector.” This judge, noting that “the main purpose of [35 U.S.C. §] 101 is to prevent preemption and to confine the inventors to what was invented,” questioned why the claims were not limited to the rh.10 vector’s use in gene therapy. Morrison responded that all the uses listed in REGENXBIO’s briefing were “related in some way to gene therapy.”
The judge pressed further, stating that the allegation that “any rh.10 attached to anything that isn’t an [adeno-associated virus] is patentable is an incredibly broad claim that reaches things that are unknown at this point.” Morrison disagreed with that characterization, reframing the issue as whether the claimed host cell is “a new composition of matter that is different than what was in nature.”
The judge remained skeptical, suggesting this argument seemed like an attempt to overcome the relevant precedent merely by asserting that attaching the isolated rh 10 vector, which is unpatentable on its own, to anything else suddenly made it patentable. Morrison countered that the claim at issue in the Supreme Court’s decision in Association for Molecular Pathology v. Myriad Genetics, Inc. was much less patentable—taking two different pieces from the same gene and joining them together—yet the Supreme Court still found it patentable.
Morrison, when responding to a judge’s question, reemphasized that REGENXBIO’s claims are broader than gene therapy because the claimed capsid proteins, as well as bacterial cells used in their production, each have their own uses. A judge followed up by asking whether case law required those functions to be explicitly recited in the claim. Morrison answered that the case law did not, citing Myriad, where patent eligibility was based on a markedly different structure rather than a recited function.
The judge, however, noted that REGENXBIO appeared to rely on unclaimed functions and suggested instead that the company would need to demonstrate a “markedly different structure” to satisfy § 101. Morrison maintained that she was not relying on unclaimed functions to establish eligibility. Nevertheless, she argued, combining the isolated capsid protein sequence with other elements and putting it into a host cell created a markedly different composition of matter, consistent with the Supreme Court’s precedent.
Robert Wilson argued for Sarepta Therapeutics. He began by arguing the claims cover an isolated, naturally occurring rh.10 sequence without any patentable additions. Although the claims include other elements, Wilson said, “all of those are admittedly conventional or well-known.”
At this point a judge suggested that combining an rh.10 vector with another genetic sequence is not conventional. In response, Wilson maintained that combining a non-AAV sequence with a naturally occurring sequence is conventional, which, he said, was admitted by the named inventors and REGENXBIO’s experts.
A judge asked why the real issue here was not one of obviousness. In response, Wilson asserted the issue is one of conventionality, given that the claims do note recite “a practical application” but instead “generic, conventional elements.” While acknowledging the claims do recite compositions of matter, Wilson said the problem is still eligibility because “the question is whether these additional elements add anything that’s markedly different structurally or functionally from the naturally occurring sequence itself.”
Wilson agreed with a judge that a method claim applying rh.10 in gene therapy might be patentable, as it would recite a practical application. He said, however, the present claims “don’t have a markedly different function.” When a judge called it “an over-claiming situation,” he agreed, saying it was “an attempt to monopolize the sequence” itself with “broad high-level elements that are just added onto the naturally occurring sequence.”
Although Wilson agreed with a judge that cultured host cells and recombinant DNA molecules do not exist in nature, he argued that non-naturality alone is insufficient to confer eligibility on the claims because of the requirement to prove “markedly different characteristics.” When this judge asked why a markedly different structure is not sufficient, Wilson responded by arguing that, under Myriad, “breaking of chemical bonds and removing something from its environment is not enough” without any meaningful structural or functional change.
In response to a question about why the dispute should not be analyzed under the enablement, non-obviousness, or novelty requirements, Wilson maintained that the relevant inquiry is whether the characteristics as well as the structure of the claimed invention are markedly different.
In her rebuttal, Morrison argued “the markedly different test is not about whether each piece of the claim is markedly different from what’s in nature.” Rather, she said, the test asks “whether the composition as a whole is markedly different than what is natural.” She further contended that because there are uses outside the claims, there is no preemption.
We will continue monitoring this case and report on developments.