Amgen bid to revive cholesterol drug patents comes to U.S. Supreme Court

[March 27, 2023]  By John Kruzel and Andrew Chung

WASHINGTON (Reuters) - The U.S. Supreme Court on Monday is set to hear a bid by Amgen Inc to revive patents on its cholesterol-lowering drug Repatha in a legal effort that rival Sanofi SA called a "blatant attempt" to squeeze competitors out of the market.

Amgen is appealing a lower court's ruling that invalidated two of its patents on Repatha, a drug that can reduce risk of heart attack and stroke in people with heart disease, after a legal fight with French drugmaker Sanofi and its partner Regeneron Pharmaceuticals Inc.

Thousand Oaks, California-based Amgen has sought to patent a group of antibodies that help reduce so-called "bad" cholesterol. At issue is whether a valid patent can cover all the members of an identified group, or if it is limited to only those members of the group specified by the patent owner.

In 2014, Amgen sued Sanofi and Regeneron for patent infringement over their rival drug Praluent, which works by a similar mechanism as Repatha. Both drugs use laboratory-made antibodies to block a protein called PCSK9 that inhibits the removal of bad cholesterol from the blood, but they achieve this result through different chemical combinations.

Bad cholesterol, known LDL, can cause a buildup of plaque in blood vessels and increase the risk of heart disease and stroke.

Amgen sold nearly $1.3 billion worth of Repatha worldwide in 2022. Regeneron sold $130 million worth of Praluent in the United States last year, and Sanofi sold more than $400 million worth in the rest of the world.

The Washington-based U.S. Court of Appeals for the Federal Circuit, which hears all patent appeals nationwide, invalidated Amgen's patents that covered PCSK9-blocking drugs as a group. The Federal Circuit in 2021 ruled that Amgen's patents granted by the government lacked the kind of detailed guidelines needed to replicate the full scope of its claims without "undue experimentation."

An Amgen sign is seen at the company's office in South San Francisco, California in this October 21, 2013 photo. REUTERS/Robert Galbraith/

Under U.S. law, a drug patent must allow a skilled scientist to replicate an invention without excessive trial and error.

Amgen told the justices the Federal Circuit wrongly applied too high a legal bar by demanding that a patent explain how to make virtually every possible version of the invention that could perform the claimed functions. It argued that a patent need only to "enable skilled artisans to 'make and use' the invention," not account for the full range of possible forms the invention might take.

Sanofi urged the justices to affirm the Federal Circuit's ruling, characterizing Amgen's bid as "a blatant attempt to corner the market."

"Amgen asserted these broad, functionally defined genus claims to literally try to take Praluent off the market and away from patients," lawyers for Sanofi wrote in a brief.

Genus claims refer to patents that cover not just one specific thing but a group of related things.

President Joe Biden's administration is supporting Sanofi in the dispute.

A ruling in the case is expected by the end of June.

(Reporting by John Kruzel and Andrew Chung; Editing by Will Dunham)

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