Amgen Sues Coherus over Neulasta with a Single Protein Purification Patent

On May 10, 2017, Amgen sued Coherus over Neulasta with a single patent that covers a method for purifying proteins.  After exchanging list of patents, Amgen and Coherus negotiated under 42 U.S.C. § 262(l)(4) as to “which, if any, patents listed under paragraph (3) by the subsection (k) applicant or the reference product sponsor shall be the subject of an action for patent infringement under paragraph (6).” Amgen and Coherus then agreed that U.S. Patent No. 8,273,707 “would be included in the action for patent infringement under 42 U.S.C. § 262(l)(6).”  Coherus has denied infringement of the ’707 Patent in its detailed statement under 42 U.S.C. § 262(l)(3)(B).

Claim 1 of the ’707 Patent recites:

A process for purifying a protein on a hydrophobic interaction chromatography column such that the dynamic capacity of the column is increased for the protein comprising

mixing a preparation containing the protein with a combination of a first salt and a second salt,

loading the mixture onto a hydrophobic interaction chromatography column, and

eluting the protein,

wherein the first and second salts are selected from the group consisting of citrate and sulfate, citrate and acetate, and sulfate and acetate, respectively, and wherein the concentration of each of the first salt and the second salt in the mixture is between about 0.1 M and about 1.0.

The ‘707 Patent does not cover dosing or a formulation of Neulasta, but is directed to a method for purifying proteins.  Is it possible that Amgen has no other Neulasta patents that Coherus infringes?  We do not know what patents were on the list that Amgen gave to Coherus, but the inclusion of a single protein purification patent in this suit does not bode well for Amgen.

AMGEN V. COHERUS (D. DEL.)