WASHINGTON — Lawyers for Sanofi-Regeneron, Amgen, and the federal government took the stage at the Supreme Court on Monday, arguing a complicated patent case over the two sides’ competing, blockbuster PCSK9 inhibitors with justices’ questions hinting at a decision that will likely be a win for Sanofi and Regeneron.
The morning opened with about 45 minutes for Amgen’s lawyer, Jeffrey Lamken, who was peppered with straightforward questions from Associate Justices Clarence Thomas and Sonia Sotomayor, with Thomas at one point asking, “I’m confused as to what your invention is?”
And that was a tall task for Lamken, who had to explain to the court why Amgen’s so-called “genus” patent, which ostensibly covers 26 amino acid sequences related to antibodies targeting PCSK9, but which Amgen says should be extended to all of the potentially millions of antibodies that might fit that bill.
Thomas at one point quipped, “You don’t know how many there are,” referring to the number of antibodies that fall under the patent.
But Lamken made the point that “antibody scientists aren’t going to consider those near-identical twins to be distinct antibodies,” as the vast majority of those millions are “99.99 percent similar, and nobody is going to consider them distinct,” adding:
But even if you were to say, well, gee, there’s a large number out there, the difficulty of making any next antibody is straightforward. The — the record is clear and the — and the patents points out that this is sort of a routine process. It’s very easy to go and say, I’m going to swap out this amino acid another.
Part of the Supreme Court’s task is to address what’s referred to as the “enablement” requirement, which essentially spells out how a patent should enable skilled artisans “to make and use” the invention.
Amgen argued that its roadmap in the patent allows for such work to be done without undue experimentation, or expensive and time-consuming trial and error, whereas Sanofi-Regeneron argued the opposite, and made clear that if Pfizer, which was one of the first companies to invest in PCSK9 inhibitors, had filed the same genus patent as Amgen, then all of the corresponding antibodies like Amgen’s Repatha (evolocumab) and Sanofi-Regeneron’s Praluent (alirocumab) would technically be owned by Pfizer.
Jake Holdreith, a partner at Robins Kaplan who was unaffiliated with the court proceedings, explained to Endpoints News that the justices “sounded like they are affirming the full scope of embodiments test,” which would be a win for Sanofi and Regeneron and that “Amgen has an uphill battle.” That decision would mean that companies would have to clearly explain how to make and develop all of the relevant antibodies that fall under the patent.
Holdreith noted that the arguments sounded like they turned on a factual disagreement (which wouldn’t likely be addressed by SCOTUS) on whether the discovery of the binding site and function “is the whole ballgame,” which was Amgen’s take, or that finding the specific antibodies is what’s key and that companies should be motivated to find other functional antibodies to that site.
Amgen’s lawyer tried to suggest to the court that finding some outlier examples (among the millions of potential ones) is not enough and merely the time it would take to identify all antibodies isn’t the test, but that the test should be up to what a person of skill knows, and what they say matters.
“There was not a lot of enthusiasm for that suggestion from SCOTUS,” Holdreith noted. Justices also questioned several times (from Associate Justices Neil Gorsuch and Elena Kagan) what the disagreement is with the law, specifically, and how they should respond.
Sanofi-Regeneron’s lawyer Paul Clement described Amgen’s patent as “over-claimed” and “under-enabled,” telling the court, “Functional genus claims are terrible” and Amgen’s “patent is invalid.” He noted that there needs to be some structure to unify the genus. Clement added:
Thomas Edison discovered the key to incandescent light, but we’d all be fumbling around in the dark if this Court had not invalidated the broad unenabled claims in Sawyer and Man’s patent in the Lamp case. The stakes here are comparable.
Colleen Sinzdak, assistant to the solicitor general, also answered questions from justices in the final 15 minutes and explained that it will be useful for SCOTUS to clarify that companies have to enable each of their inventions. The federal government, Pfizer, Viatris and others have sided with Sanofi-Regeneron via amici briefs.

So what to expect when SCOTUS issues its decision? Holdreith predicts there will be more nuance, and some additional gloss on how to decide if and which examples matter in a patent, and what a reasonable person of skill would find important. He said any decision may provide an opportunity for good lawyers to have another issue to dispute in court, and he’s not sure it’ll provide the clarity that both sides are looking for in this case.
Regeneron CEO Len Schleifer was in attendance at the oral arguments today and told Endpoints afterwards, “I was very impressed with the process, but not Amgen’s arguments.”
2023-03-27 19:55:00