Supreme Court Affirms Federal Circuit Ruling Regarding Satisfaction Of Enablement Requirement

• Jurisdiction: United States,Federal
• Law Firm: Duane Morris LLP
• Subject Matter: Intellectual Property, Patent
• Author: Mr Thomas J. Kowalski, Deborah L. Lu, Ph.D. and Brandon A. Chan, Ph.D.
• Published date: 30 May 2023

On May 18, 2023, the Supreme Court of the United States issued its opinion in Amgen, Inc. v. Sanofi, which clarified the standard of satisfying the enablement requirement, in particular, for broad functional genus claims.

Conceptual Background

LDL, or low-density lipoprotein, cholesterol is often termed "bad" cholesterol. Excessive amounts can lead to buildup of plaque in the arteries and increase the risk of developing cardiovascular disease, heart attack and stroke. The body produces LDL receptors to facilitate the removal of LDL from the bloodstream. One particular protein of interest, PCSK9, is known to bind to LDL receptors and inhibit removal of LDL. It is beneficial to target PCSK9 and inhibit its ability to interfere with LDL receptors, thereby lowering LDL levels in the body and reducing the risk of developing further disease. There are numerous drugs that target PCSK9, for example, Repatha, marketed by Amgen, and Praluent, marketed by Sanofi. Each manufacturer has a patent directed to the specific amino acid sequence of the antibody that accomplishes the PCSK9 inhibition.

Patents at Issue

Amgen owns U.S. Patent Nos. 8,829,165 ('165 patent) and 8,859,741 ('741 patent), which are directed to an entire genus of antibodies that 1) bind to specific amino acid residues on PCSK9 and 2) block PCSK9 from binding to LDL receptors. The claims thus recite a function of the antibody, rather than the specific antibody sequences that are capable of accomplishing these functions. Amgen identified the sequence of 26 antibodies that performed the claimed functions and showed the 3D structures of two of these antibodies in its patent application. In teaching how to make other antibodies, Amgen offered a "road map" method in which scientists develop a range of antibodies, investigate their binding to the specific amino acid residues of PCSK9, and determine whether any of these antibodies block PCSK9 from binding to LDL receptors. Amgen also taught a "conservative substitution" method to make other antibodies, in which an antibody performing the claimed functions has select amino acids substituted with other amino acids having similar activity. Then the binding of the modified antibody is evaluated for its performance of the claimed functions.

Case History

Amgen sued Sanofi alleging infringement of the '165 and '741 patents. Sanofi alleged that the patents at issue were invalid because Amgen, while identifying the 26 antibodies that perform the claimed functions...