Amgen v. Sanofi: Implications for ANDA and aBLA Parties

Pharmaceutical innovators typically seek broad patent protection for their discoveries in order to prevent others from exploiting not only the specific embodiments the innovator wishes to pursue commercially, but also functional equivalents. But what happens when the additional functional equivalents that the innovator seeks to protect are not expressly disclosed in the patent? The Supreme Court recently addressed this issue in Amgen v. Sanofi.

In Amgen v. Sanofi, the Court considered two patents collectively claiming an entire genus of antibodies performing two functions associated with reducing low-density lipoprotein (LDL) cholesterol in the body: (1) they “bind to specific amino acid residues on PCSK9” – a naturally occurring protein associated with LDL cholesterol; and (2) they “block PCSK9 from binding to [LDL receptors].” The patents described twenty-six exemplary antibody amino acid sequences that perform the claimed binding and blocking functions, along with two proposed methods for making and using other antibodies performing these functions. The claims, on the other hand, covered potentially millions of antibodies that performed the claimed functions. In a unanimous decision, the Supreme Court affirmed the lower courts’ judgment that the claims were invalid for lack of enablement under 35 U.S.C. § 112(a).^[1]The Court applied a “simple statutory command” gleaned from its prior enablement decisions: “the specification must enable the full scope of the invention as defined by its claims. The more one claims, the more one must enable.” While the Court recognized that the enablement requirement does not necessarily require a description of “how to make and use every single embodiment within a claimed class,” it found that the guidance provided in Amgen’s patents for making and using potentially millions of undisclosed antibodies “offers persons skilled in the art little more than advice to engage in ‘trial and error.’”

The Supreme Court’s decision in Amgen v. Sanofi will no doubt have an impact on the pharmaceutical industry, creating questions for innovators who wish to obtain and enforce broad genus patents. The Court’s “[t]he more one claims, the more one must enable” test, while simple, begs the question “how much disclosure is enough?” While the Supreme Court made clear that patentees need not disclose each and every embodiment in a claimed genus, the line between “a reasonable degree of experimentation” required to obtain undisclosed species (acceptable) and an invitation for “trial and error” (not acceptable) will not always be clear. Amgen v. Sanofi reinforces the need for patentees to consider disclosure and claiming strategies early on during product discovery and development, rather than waiting for the patent application process. In addition to balancing disclosing more examples, and claiming smaller genuses, patentees should focus on identifying and disclosing structural qualities “common to every other functional embodiment” that the patentee seeks to claim, rather than relying solely on functional attributes.

The Supreme Court’s decision in Amgen v. Sanofi also will impact ANDA and 351(k) filers developing their pre-litigation strategies for challenging innovator patents.^[2]Applicants using the abbreviated pathways for reference pharmaceuticals and biologics often must contend with vast patent portfolios covering a multitude of aspects of the reference products, including their compositions, formulations, and processes. Historically, patents directed towards molecules for pharmaceuticals and antibodies or other proteins for biologics have been considered relatively high patent barriers for ANDA and biosimilar applicants to overcome. The Supreme Court’s decision lends support to ANDA and 351(k) filers who seek to challenge existing portfolios, particularly those dependent on broad functional claims. While the patents in Amgen v. Sanofi were directed to antibodies and genus claims, it is important to note that the Supreme Court’s decision was not so limited, and applies to all patentable subject matter. Thus, generic and biosimilar applicants seeking early approval via an abbreviated pathway should consider this decision when evaluating the innovator’s patent portfolio, regardless of whether the patents are directed to compositions of matter, formulations, or manufacturing processes.

While the full impact of Sanofi v. Amgen remains to be seen, the Supreme Court’s decision is a reminder to patentees and competitors alike of the importance of patent disclosure and enablement, and the need to balance the time and cost of disclosure with the potential risk of invalidity due to overclaiming.