THE MORE YOU CLAIM, THE MORE YOU MUST ENABLE
| July 12, 2023
Amgen Inc. v. Sanofi
Decided: May 18, 2023
Supreme Court of the United States. Opinion by Justice Gorsuch
Summary:
Amgen owns patents covering antibodies that help reduce levels of low-density lipoprotein (LDL) cholesterol. Amgen sued Sanofi for infringement of its patents in district court. Sanofi raised the defense of invalidity for lack of enablement because while Amgen provided amino acid sequences for 26 antibodies, the claims cover potentially millions more undisclosed antibodies. The district court granted a motion for JMOL for invalidity due to lack of enablement, the CAFC affirmed, and the Supreme Court affirmed.
Details:
Amgen’s patents are to PCSK9 inhibitors. PCSK9 is a naturally occurring protein that binds to and degrades LDL receptors. PCSK9 causes problems due to degradation of LDL receptors because LDL receptors extract LDL cholesterol from the bloodstream. A method used to inhibit PCSK9 is to create antibodies that bind to a particular region of PCSK9 referred to as the “sweet spot” which is a sequence of 15 amino acids out of PCSK9’s 692 total amino acids. An antibody that binds to the sweet spot can prevent PCSK9 from binding to and degrading LDL receptors. Amgen developed a drug named REPATHA and Sanofi developed a drug named PRALUENT, both of which provide a distinct antibody with its own unique amino acid sequence. In 2011, Amgen and Sanofi received patents covering the antibody used in their respective drugs.
The patents at issue are U.S. Patent Nos. 8,829,165 and 8,859,741 issued in 2014 which relate back to Amgen’s 2011 patent. These patents are different from the 2011 patents in that they claim the entire genus of antibodies that (1) “bind to specific amino acid residues on PCSK9,” and (2) “block PCSK9 from binding to LDL receptors.” The relevant claims are provided:
Claims of the ‘165 patent:
1. An isolated monoclonal antibody, wherein, when bound to PCSK9, the monoclonal antibody binds to at least one of the following residues: S153, I154, P155, R194, D238, A239, I369, S372, D374, C375, T377, C378, F379, V380, or S381 of SEQ ID NO:3, and wherein the monoclonal antibody blocks binding of PCSK9 to LDLR.
19. The isolated monoclonal antibody of claim 1 wherein the isolated monoclonal antibody binds to at least two of the following residues S153, I154, P155, R194, D238, A239, I369, S372, D374, C375, T377, C378, F379, V380, or S381 of PCSK9 listed in SEQ ID NO:3.
29. A pharmaceutical composition comprising an isolated monoclonal antibody, wherein the isolated monoclonal antibody binds to at least two of the following residues S153, I154, P155, R194, D238, A239, I369, S372, D374, C375, T377, C378, F379, V380, or S381 of PCSK9 listed in SEQ ID NO: 3 and blocks the binding of PCSK9 to LDLR by at least 80%.
Claims of the ‘741 patent:
1. An isolated monoclonal antibody that binds to PCSK9, wherein the isolated monoclonal antibody binds an epitope on PCSK9 comprising at least one of residues 237 or 238 of SEQ ID NO: 3, and wherein the monoclonal antibody blocks binding of PCSK9 to LDLR.
2. The isolated monoclonal antibody of claim 1, wherein the isolated monoclonal antibody is a neutralizing antibody.
7. The isolated monoclonal antibody of claim 2, wherein the epitope is a functional epitope.
In its application, Amgen identified the amino acid sequences of 26 antibodies that perform these two functions. Amgen provided two methods to make other antibodies that perform the described binding and blocking functions. Amgen refers to the first method as the “roadmap,” which provides instructions to:
(1) generate a range of antibodies in the lab; (2) test those antibodies to determine whether any bind to PCSK9; (3) test those antibodies that bind to PCSK9 to determine whether any bind to the sweet spot as described in the claims; and (4) test those antibodies that bind to the sweet spot as described in the claims to determine whether any block PCSK9 from binding to LDL receptors.
Amgen refers to the second method as “conservative substitution” which provides instructions to:
(1) start with an antibody known to perform the described functions; (2) replace select amino acids in the antibody with other amino acids known to have similar properties; and (3) test the resulting antibody to see if it also performs the described functions.
Amgen sued Sanofi for infringement of claims 19 and 29 of the ‘165 patent and claim 7 of the ‘741 patent. Sanofi raised the defense of invalidity because Amgen had not enabled a person skilled in the art to make and use all of the antibodies that perform the two functions Amgen described in the claims. Sanofi argued that Amgen’s claims cover potentially millions more undisclosed antibodies that perform the same two functions than the 26 antibodies identified in the patent.
The court provided an explanation of the law and policy regarding the enablement requirement. 35 U.S.C. § 112 requires that a specification include “a written description of the invention, and of the manner and process of making and using it, in such full, clear, concise, and exact terms as to enable any person skilled in the art … to make and use the same.” The court stated:
the law secures for the public its benefit of the patent bargain by ensuring that, upon the expiration of [the patent], the knowledge of the invention [i]nures to the people, who are thus enabled without restriction to practice it.
The court stated that “the specification must enable the full scope of the invention as defined by its claims.” Specifically, the court stated:
If a patent claims an entire class of processes, machines, manufactures, or compositions of matter, the patent’s specification must enable a person skilled in the art to make and use the entire class.
The court emphasized that the enablement requirement does not always require a description of how to make and use every single embodiment within a claimed class. A few examples may suffice if the specification also provides “some general quality … running through” the class. A specification may also not be inadequate just because it leaves a skilled artisan to engage in some measure of adaptation or testing, i.e., a specification may call for a reasonable amount of experimentation to make and use a patented invention. “What is reasonable in any case will depend on the nature of the invention and the underlying art.”
Regarding this case, the court stated that while the 26 exemplary antibodies provided by Amgen are enabled by the specification, the claims are much broader than the specific 26 antibodies. And even allowing for a reasonable degree of experimentation, Amgen has failed to enable the full scope of the claims.
The court stated that Amgen seeks to monopolize an entire class of things defined by their function and that this class includes a vast number of antibodies in addition to the 26 that Amgen has described by their amino acid sequences. “[T]he more a party claims, the broader the monopoly it demands, the more it must enable.”
Amgen argued that the claims are enabled because scientists can make and use every undisclosed but functional antibody if they simply follow Amgen’s “roadmap” or its proposal for “conservative substitution.” The court stated that these instructions amount to two research assignments and that they leave scientists “forced to engage in painstaking experimentation to see what works.” The court referred to Amgent’s two methods as “a hunting license.”
Comments
The key takeaway from this case is that the broader your claims are, the more your specification must enable. If it is difficult to show enablement for every embodiment claimed, then make sure your specification describes some general quality throughout the class or genus. A reasonable amount of experimentation is permissible for enablement, but reasonableness will depend on the nature of the invention and the underlying art.
