United States: Industry Impact: Supreme Court Equates Broad Repatha® Antibody Patents To A "Hunting License" In Amgen v. Sanofi

The Supreme Court last week unanimously affirmed a Federal Circuit decision finding that patent claims for Amgen's Repatha® that cover "the entire genus" of antagonist antibodies involved in regulating LDL cholesterol are invalid. The Court held that the patents at issue do not sufficiently enable a person of ordinary skill in the art to make and use the claimed invention as required by 35 U.S.C. § 112(a). This lawsuit, brought by Amgen against Sanofi and Regeneron, has captivated the life sciences industry for the past nine years. The decision is expected to have widespread impact on patent and investment strategies.

The dispute stemmed from two patents obtained by Amgen in 2014 claiming the entire genus of antibodies that—as defined by their function—bind to certain amino acid residues (the "sweet spot") on PCSK9 and block PCSK9 from binding to LDL receptors. Despite the claim scope, potentially encompassing millions of antibodies as argued by Sanofi and Regeneron, the Amgen patents disclose the primary structures (amino acid sequences) of only 26 antibodies.

To identify all other antibodies falling within the claimed genus, the patents describe two alternative methods: (1) a "roadmap" for finding additional antibodies, or (2) "conservative substitution" of select amino acids on the antibodies already known to work. Under both methods, scientists would need to test whether the candidate antibodies bind to the "sweet spot" and block PCSK9 from binding to LDL receptors. Amgen argued that these two methods sufficiently disclosed to the public how to make and use the entire claimed genus of anti-PCSK9 antibodies without undue experimentation.

The Supreme Court disagreed. It equated Amgen's disclosed methods to a "hunting license," "research assignments," and "little more than advice to engage in 'trial and error.'" Justice Gorsuch hearkened back to centuries of precedent—including cases involving Samuel Morse's telegraph and Thomas Edison's bamboo light bulb filament—to strike a balance between what a patentee must disclose to the public when claiming a broad genus and what a patentee is entitled to monopolize under the great "patent bargain" enshrined in Article I, Section 8, Clause 8 of the Constitution. The Court concluded that "the more one claims, the more one must enable."

While agreeing that there is only one enablement standard for all types of claims, the Court disposed of Amgen's arguments that the Federal Circuit erroneously "raised the bar" for enablement of genus claims. Relying solely on its own precedents, the Court did not discuss, however, the Federal Circuit's longstanding Wands factors for determining what constitutes undue experimentation.

R&D and Investment Impact

Numerous industry players weighed in by submitting amicus briefs for the Supreme Court's certiorari. GlaxoSmithKline and AbbVie, in support of Amgen, insisted that broad genus claims incentivize investment in R&D and that affirmance of the Federal Circuit's decision to invalidate Amgen's patents would stifle breakthrough inventions. Industry amici in support of Sanofi and Regeneron's position—Genentech, AstraZeneca, Bayer, Gilead, Pfizer, Johnson & Johnson, and Eli Lilly—argued that unjustly broad patent claims hamper innovation.

The Court stated that striking the proper balance is a policy judgment belonging to Congress and the Court's duty is to apply the statutory requirement for enablement "faithfully." Justice Gorsuch also pondered that without the balance struck by Congress' enablement mandate in the Patent Act of 1790, Edison may never have commercialized his light bulb filament, and the Court, too, may have been left sitting in the dark.

This decision continues the legal trend of increased scrutiny for broad patent claims. Broad functional patents are now potentially more vulnerable under the Supreme Court's decision, which may implicate how biopharma companies and investors interpret freedom-to-operate hurdles posed by those patents.

Retrospective Enforcement Strategy

Patent holders seeking to protect their investments by enforcing existing broad genus patents will have to expect non-enablement arguments. Patent holders may consider focusing on the robustness of the specification and asserting the narrowest possible claims that will capture a potential infringer literally or under the doctrine of equivalents.

This may also force patent holders to seek reissued patents with narrower claims and also to adjust future patent prosecution strategies. For example, patent holders may want to procure narrower claims, if the patent family is still pending, in a continuing application.

On the other hand, accused infringers will undoubtedly rely on the Supreme Court's decision to assert invalidity of patent claims covering broad biotherapeutic classes.

Prospective Patent Procurement Trends

Under the enablement standard reaffirmed by the decision, patent applicants seeking broad functional claims, such as for a class of antibodies, should consider providing data and guidance in their disclosures to the Patent Office commensurate with the breadth of claims sought. As the Supreme Court noted, claiming broadly does permit a "reasonable amount" of experimentation and providing "an example (or a few examples)" from a genus may suffice so long as the specification "also discloses some general quality...running through the class that gives it a peculiar fitness for the particular purpose."

The specific interpretation of this language will be argued by litigants and patent prosecutors in the future. Given that the Supreme Court found that the PCSK9 epitope disclosed in Amgen's patents was insufficient, applicants should consider common features or qualities that can be disclosed to mitigate undue experimentation.

R&D, investment, patent litigation, and patent prosecution strategies in the life sciences industry all should account for this recent decision, and it remains to be seen how future enablement jurisprudence will continue to evolve and affect the industry in the long term.

The case is Amgen Inc., et al. v. Sanofi, et al., No. 21?757. Here is a link to the opinion.

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