In its recent decision in Baxalta Inc. v. Genentech, Inc., No. 2022-1461, 2023 WL 6135930 (Fed. Cir. Sept. 20, 2023), the Federal Circuit applied the Supreme Court’s decision in Amgen Inc. v. Sanofi to affirm the District of Delaware’s grant of summary judgment of lack of enablement for broad antibody claims that specify what the antibody does rather than what the antibody is.
The claims at issue in Baxalta are directed to a genus of antibodies that perform a specific function – binding to a target and triggering a response. Specifically, claim 1 of U.S. Patent No. 7,033,590 is directed to:
1. An isolated antibody or antibody fragment thereof that binds Factor IX or Factor IXa and increases the procoagulant activity of Factor IXa.
The Federal Circuit found the facts of this case to be “materially indistinguishable from those in Amgen.” Baxalta, 2023 WL 6135930, at *4. According to the Federal Circuit, claim 1 covers “millions of potential candidate antibodies” (id.) that bind to Factor IX/IXa and increase the procoagulant activity of Factor IXa. The court, however, noted that the specification discloses the amino acid sequence of just 11 of those antibodies. And like the roadmap in the patents at issue in Amgen, “the ’590 patent’s roadmap simply directs skilled artisans to engage in the same iterative, trial-and-error process the inventors followed to discover the  antibodies they elected to disclose.” (Id.) Missing from the specification, according to the Federal Circuit, was “‘a quality common to every functional embodiment’ ... that would allow a skilled artisan to predict which antibodies will perform the claimed functions” (id.; quoting Amgen Inc. v. Sanofi, 598 U.S. 594, 614 (2023)), such as a common structural or other feature that would allow the antibodies to perform the claimed functions, or an explanation as to why the 11 antibodies do so and others do not. (Baxalta, 2023 WL 6135930, at *4). And the Federal Circuit was not persuaded by Baxalta’s argument that its disclosed hybridoma-and-screening process “predictably and reliably generates new claimed antibodies every time it is performed” (id.), because “it is undisputed that to practice the full scope of the claimed invention, skilled artisans must make candidate antibodies and screen them to determine which ones perform the claimed functions.” (Id.)
In line with the Amgen decision, the Federal Circuit is looking for “a quality common to every functional embodiment.” In the antibody context, this appears to mean structural features of the antibody or at least an explanation as to why some antibodies satisfy the functional requirements and others do not.