When is Evidence of Written Description Too Late?
| October 24, 2017
Amgen v. Sanofi
October 5, 2017
Before Prost, Taranto and Hughes. Opinion by Judge Prost.
Procedural History:
The two patents-in-suit disclose and claim a set of antibodies. The following claim is representative:
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 LDL[-]R.
The technical background of the invention involves statins that are administered to patients to reduce high levels of LDL-C in the blood. When these statins do not work, doctors sometimes administer PCSF9 inhibitor as well – PCSK9 being a naturally occurring protein that binds to and destroys liver cell LDL-receptors that take LDL-C from the blood.
The claim recites a genus of antibodies that bind to PCSK9 at the recited residue sites, thereby preventing PCSK9 from interfering with LDL-C removal from the blood.
The specification, common to both patents, discloses “85 antibodies that blocked interaction between the PCSK9 . . . and the LDLR [at] greater than 90%,” It also discloses the three-dimensional structures, obtained via x-ray crystallography, of two antibodies known to bind to residues recited in the claims—21B12 (Repatha) and 31H4.
Appellant/Defendant Sanofi markets an antibody named Praluent® alirocumab. Appellee/Patentee sued Sanofi for patent infringement. Sanofi replied, inter alia, that the claims did not comply with the written description and enablement requirements.
In a jury trial, the judge excluded from the evidentiary record all post-priority-date information that Sanofi proffered to show that the written description and enablement requirements were not met. Specifically, Sanofi’s proffered evidence that included its own later-developed Praluent product that was developed after the priority date of Amgen’s patents.
Ultimately, the jury issued a verdict that the patents were valid and infringed.
The CAFC reversed the trial judge’s exclusionary ruling and vacated the jury’s verdict. It first set forth the legal background, specifically, that a patentee must convey in its disclosure that it “had possession of the claimed subject matter as of the filing date” and that to provide this “precise definition” for a claim to a genus, a patentee must disclose “a representative number of species falling within the scope of the genus or structural features common to the members of the genus so that one of skill in the art can ‘visualize or recognize’ the members of the genus.” (Emphasis added).
Here, Sanofi’s evidence regarding Praluent was relevant to the material issue of whether the two patents disclosed a representative number of species within the claimed genus. The CAFC therefore held that the trial judge erred in excluding Sanofi’s evidence and ordered a new trial on written description. It also ordered a new trial on enablement for the same reasons.
The CAFC summarized the legal basis for its holding: evidence that explains the state of the art after the priority date is not relevant to written description. On the other hand, where a patent claims a genus, it must disclose “a representative number of species falling within the scope of the genus or structural features common to the members of the genus so that one of skill in the art can ‘visualize or recognize’ the members of the genus.” Accordingly, evidence showing that a claimed genus does not disclose a representative number of species may include evidence of species that fall within the claimed genus but are not disclosed by the patent, and evidence of such species is likely to postdate the priority date.
Take Away
The lesson is that the purpose for which post-priority date evidence is proffered determines whether it is admissible.
