TEVA PHARMACEUTICALS INTERNATIONAL GMBH v. ELI LILLY AND COMPANY
Authored by: Jeremy J. Gustrowsky
A jury found that Eli Lilly willfully infringed three Teva patents covering methods of treating headaches using humanized anti-CGRP antagonist antibodies. The district court then overturned that verdict, ruling as a matter of law that the patents were invalid because their specification did not adequately describe or enable the full scope of the claimed antibodies. The Federal Circuit disagreed and reversed, reinstating the jury’s verdict and drawing an important line between claiming a class of biological molecules and claiming a method of using that class for a specific medical purpose.
The patents at issue (U.S. Patent Nos. 8,586,045, 9,884,907, and 9,884,908) relate to Teva’s Ajovy product and cover methods of treating headache by administering humanized anti-CGRP antagonist antibodies. CGRP is a protein associated with headache when it binds to certain cell receptors, and these antibodies work by blocking that binding. Although the specification disclosed only one specific humanized antibody (“G1”), it also described several non-humanized (murine) versions and referenced well-known techniques for converting them into humanized forms suitable for use in humans. Lilly argued that disclosing just one humanized species was not enough to support claims covering the entire genus of humanized anti-CGRP antagonist antibodies.
The Federal Circuit found that the jury had good reason to reject Lilly’s invalidity arguments. The court pointed to Lilly’s own statements in earlier proceedings before the Patent Trial and Appeal Board, where Lilly had characterized anti-CGRP antagonist antibodies as “well known in the art” and “replete” in the prior art, and had called humanization a “well-established and routine procedure.” Critically, neither side disputed that a skilled artisan reading the specification would have understood that all humanized anti-CGRP antagonist antibodies would treat headache. With antibodies well known, humanization routine, and efficacy across the genus undisputed, the court concluded the specification disclosed enough representative species for the purpose of the claimed invention.
The court leaned on a line of precedent distinguishing between patents that claim a genus of compositions outright and patents that use a well-known genus as part of a different invention. Cases like Ajinomoto, Herschler, and Fuetterer established that when the genus itself is not the invention but rather a known input to a new method, the disclosure burden is lighter. The court distinguished Amgen v. Sanofi and Baxalta, where claims covered entire antibody genera for any and all purposes, requiring extensive trial-and-error experimentation to identify members. Here, the claims were limited to using the antibodies for headache treatment, and since all members of the genus worked for that purpose, there was no “research assignment” left to complete. The court also rejected Lilly’s reliance on Idenix, where (unlike here) the evidence did not support a finding that all members of the claimed genus were effective for the claimed treatment.
This decision is a significant win for Teva and reinforces that context matters in written description and enablement disputes. A patent applicant claiming a new use for a well-understood class of compounds may not need to individually describe every member of that class, particularly when the specification makes clear they all work for the claimed purpose.