In an update on the Amgen v. Coherus appeal regarding Coherus’s biosimilar application for pegfilgrastim, Amgen filed its opening brief on August 20. Amgen’s statement of the issues are:

1. Whether the district court erred in dismissing Amgen’s Complaint, with prejudice, based on prosecution history estoppel where the single filewrapper statement relied upon by the district court—that the pending claims recite a “particular combination of salts”—is at best ambiguous as to whether it was meant to limit the claims to three salt-pairs or whether it referred to the discovery that the salt combinations useful to obtain the benefits of the invention (i.e., increasing the dynamic capacity of the HIC column) are particularly selected for any specific protein to be purified, and in view of this ambiguity the statement is not a clear and unmistakable disclaimer of claim scope; and
2. Whether the district court erred in dismissing Amgen’s Complaint, with prejudice, based on the dedication-disclosure doctrine where the specification does not explicitly disclose the subject matter—use of the [REDACTED] practiced by Coherus—that was found to be dedicated to the public.

We have been reporting on the Genentech v. Amgen trastuzumab litigation. Amgen had answered Genentech’s amended complaint with affirmative defenses and counterclaims of, among other things, non-infringement, invalidity and, with respect to one patent, unenforceability due to unclean hands and inequitable conduct. On August 23, Genentech filed a motion to dismiss Amgen’s counterclaims of unenforceability and its affirmative defense of unclean hands. Genentech alleges that Amgen’s counterclaims for unenforceability are “baseless and boilerplate assertions [that] do not meet the pleading requirements of Federal Rule of Civil Procedure 12(b)(6), much less the heightened pleading burden of Federal Rule of Civil Procedure 9(b) that is required for claims of inequitable conduct.” Genentech further alleges that Amgen’s unclean hands defense is “legally inadequate” because “Amgen does not allege that Genentech deliberately concealed references in its possession from the Patent Office.”

We had recent coverage of Immunex’s patent infringement suit regarding Sanofi and Regeneron’s Dupixent® (dupilumab) biologic and Immunex’s renewed motion to stay the district court proceeding pending the outcome of Sanofi’s IPR on the ’487 patent. On August 31, the district court denied that motion.