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Failing to disclose

Prior art that’s relevant

Can doom a patent

'Adrenaline and epinephrine are the same thing, this one is for injection' by jlcampbell104 is marked with CC PDM 1.0Trying to hide something from the US Patent and Trademark Office (USPTO) can constitute inequitable conduct that can lead to a patent being unenforceable.

The recent Federal Circuit decision in Belcher Pharmaceuticals, LLC v. Hospira, Inc. involved a patent infringement suit involving U.S. Patent No. 9,283,197, which Belcher asserted against Hospira.

The patent relates to injectable formulations of l-epinephrine. As the Circuit court noted,

Epinephrine (also called adrenaline) is a hormone as well as a grandfathered drug product that has been on the market since approximately 1938 and used for a variety of medical purposes.

In 2012, Belcher submitting a New Drug Application (“NDA”) for a 1 mg/mL injectable l-epinephrine formulation.

An NDA is the means by which drug sponsors formally propose that the US Food and Drug Administration (FDA) approves a new pharmaceutical for sale and marketing.

Belcher’s NDA, as the court noted, was “literature-based, meaning that Belcher did not perform any clinical or nonclinical studies on its epinephrine formulation to support its application.” I.e., the literature was “prior art.”

As the FDA explains,

A drug developer must include everything about a drug—from preclinical data to Phase 3 trial data—in an NDA. Developers must include reports on all studies, data, and analyses. Along with clinical results, developers must include:

    • Proposed labeling
    • Safety updates
    • Drug abuse information
    • Patent information
    • Any data from studies that may have been conducted outside the United States
    • Institutional review board compliance information
    • Directions for use

In 2014, Belcher filed a patent application covering epinephrine formulations within a specific pH range. The patent was granted in 2016, on the basis that

[T]here is nothing in the prior art that would teach or suggest the instantly claimed pH range of between 2.8 and 3.3 would result in the limited racemization and impurities as instantly claimed.

For an invention to be patentable, it must be “new.” The existence of prior art can show that an invention has already been conceived of by others, and thus isn’t “new.” Prior art can include existing products, prior patents, and patent applications, articles, etc.

Hospira also submitted an NDA seeking approval of an injectable l-epinephrine formulation, and Belcher sued Hospira for patent infringement.

As the Federal Circuit noted,

Inequitable conduct is a defense to patent infringement that, if proven, renders the asserted patent unenforceable. … To prevail on an inequitable conduct defense, a defendant must establish both the materiality of the withheld reference and the applicant’s intent to deceive the PTO.

At trial, Belcher’s Chief Science Officer admitted that he knew of relevant prior art that wasn’t disclosed during the prosecution of the patent at issue. In fact, he cited that prior art to the FDA during the NDA approval process.

As the Federal Circuit explained,

A prior art reference may constitute material information, even where the reference is not sufficient to invalidate the claim in district court if the disclosure of the reference would have blocked the issuance of a patent under the PTO’s evidentiary standards. … Thus, prior art is but-for material information if the PTO would not have allowed a claim had it been aware of the undisclosed prior art.

The district court concluded that clear and convincing evidence demonstrated that the Chief Science Officer acted with the requisite intent to deceive the USPTO. The Federal Circuit agreed:

To satisfy the intent requirement, ‘the accused infringer must prove by clear and convincing evidence that the applicant knew of the reference, knew that it was material, and made a deliberate decision to withhold it.’

Thus, the Federal Circuit upheld the lower court’s decision that the patent was unenforceable for inequitable conduct.


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