Beware What You Say To The FDA
Contributed by Oblon. Originally published on Patexia; republished here as part of the LexDana archive.
In Intendis v Glenmark, the Federal Circuit affirmed a finding of infringement under the doctrine of equivalents based on statements made by Glenmark to the FDA. The issue was whether isopropyl myristate in Glenmark’s formulation was equivalent to claimed elements triglyceride and lecithin and, more specifically, whether the claimed elements were penetration enhancers. Interestingly, the Federal Circuit went out of its way to note that it was not addressing the differences in chemical structure of the compounds.
Glenmark’s ANDA contained repeated statements that isopropyl myristate and the claimed elements function as penetration enhancers in their respective formulations, and the Federal Circuit relied on these statements:
“Fatal to Glenmark’s argument is its own ANDA submission to the FDA repeatedly referring to the claimed excipients (triglyceride and lecithin) as penetration enhancers … We see no reason why a district court acting as a fact finder should ignore a party’s representation to a federal regulatory body that is directly on point.”
This is reminiscent of the Federal Circuit’s 2005 decision in Bruno v. Acorn. In Bruno, the issue was whether the patentee (Bruno) had engaged in inequitable conduct because it was telling the USPTO that its stairlift was new and not obvious to obtain a patent at the same time it was telling the FDA that its stairlift was “substantially equivalent” and “similar in design and function” to a prior art stairlift (Wecolator) to obtain marketing approval. Bruno did not provide the Wecolator prior art to the USPTO. Suffice it to say, the Federal Circuit did not buy Bruno’s explanation:
“Bruno argues that its claim of ‘substantial equivalence’ between the SRE-1500 stairlift and the Wecolator was relevant only for the purpose of securing FDA approval, and that it had no bearing on whether Bruno knew the Wecolator to be material prior art for purposes of patentability. This distinction is disingenuous in light of what the record reflects…”
The moral of the story here: make sure your statements to regulatory bodies such as the FDA are consistent with those you make to the USPTO or in litigation, whether it’s in the context of ANDA, GRAS (generally recognized as safe), or another submission. And it’s best to ensure consistency at the time of making the statements -- otherwise, it could be too late, and you might be left with nothing more than “disingenuous” arguments.
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