In Nuvo Pharmaceuticals v. Dr. Reddy’s Laboratories (Fed. Cir. 2019), the Federal Circuit held that a patent on a claimed pharmaceutical formulation was invalid for having an inadequate written description, even though the patent disclosed, in sufficient detail, effective formulations.

Dr. John Plachetka, working for Nuvo Pharmaceuticals, conceived of a naproxen formulation which would reduce the gastrointestinal discomfort in both the stomach and small intestine normally experienced with taking an NSAID. Nuvo secured a patent (U.S. 6,926,907, “the ‘907 patent”), on which it sued Dr. Reddy’s and other generic pharmaceutical producers for infringement. The ‘907 patent describes a tablet that would coordinate the release of the NSAID naproxen with an acid inhibitor (e.g., omeprazole, esomeprazole or another proton pump inhibitor (“PPI”).

Dr. Reddy’s challenged the validity of the ‘907 patent claims for failure to provide a written description that satisfied the requirements of 35 U.S.C. §112, twice: once at trial, where the challenge failed, and again on appeal to the Federal Circuit Court of Appeals, where the challenge succeeded.

The idea of using PPI acid inhibiters with NSAIDs to alleviate the stomach discomfort caused by NSAIDs, which was assumed to be related to stomach acid, was known prior to the ‘907 patent. Dr. Plachetka had proposed an enteric coating around the NSAID that prevents its release before stomach acids are suppressed, i.e., until the pH increases to a certain desired level specified in the claims. He also envisioned including an acid inhibitor like PPI on top of the enteric coating, to suppress the production of acids and allow the pH in the stomach to rise to the desired level. The claims required leaving some of the PPI unprotected by the enteric coating, even though it would have been assumed in the art that stomach acids would destroy the PPI and leave the small intestine vulnerable. Thus, leaving the PPI outside the enteric coating was a nonobvious approach. Dr. Reddy’s challenge to the patent at trial included an argument that the patent disclosure, which provided no experimental data to demonstrate the therapeutic effectiveness of any amount of uncoated PPI, did not satisfy the disclosure requirement of 35 U.S.C. §112. Despite the absence of such data, the trial court found the disclosure to be adequate as a question of fact, and held the patent to be valid.

On appeal, Dr. Reddy’s maintained the position that the disclosure of the ‘907 patent did not provide adequate support for the claims even though it disclosed sample formulations whose effectiveness were not at issue. The Federal Circuit, obliged to affirm the trial court’s finding unless there was clear error, scoured the patent disclosure to find support for the trial court’s conclusion. Finding none, the appeals court sided with Dr. Reddy’s and held the patent to be invalid.

In its decision, the Federal Circuit pointed out that to satisfy 35 U.S.C. 112, a patent disclosure must do more than enable one skilled in the art to practice the invention; the disclosure must demonstrate that the inventor ‘possessed’ the invention. When a person of ordinary skill in the art reading the specification would not recognize that a formulation containing uncoated PPI would be effective, it was incumbent on the inventor to do more than simply describe a working embodiment: the specification must show the reader that the claimed result had been attained, by disclosing experimental data, or otherwise.  The ‘907 patent taught how to make and use Dr. Plachetka’s envisioned formulation, but it failed to convey that he had done so and achieved the claimed result. In finding the patent invalid, the Court said:

the fact that an invention may be enabled does not mean it is adequately described, and vice versa. [cite]. That is because “[t]he purpose of the written description requirement is broader than to merely explain how to `make and use’ [the invention].” [cite] The focus of the written description requirement is instead on whether the specification notifies the public about the boundaries and scope of the claimed invention and shows that the inventor possessed all the aspects of the claimed invention.

The Nuvo decision thus serves as a reminder that when the efficacy of a claimed invention would be in doubt according to conventional wisdom in the art, it is incumbent on the inventor and the patent drafter to demonstrate that the invention is more than a hypothesis. Including the results of experimental data to show that the inventor was “in possession” of the invention can be crucial for this purpose.

Frederick Spaeth

This article is for informational purposes, is not intended to constitute legal advice, and may be considered advertising under applicable state laws. The opinions expressed in this article are those of the author only and are not necessarily shared by Dilworth IP, its other attorneys, agents, or staff, or its clients.