On Sep. 01, 2021, Federal Circuit affirmed the Delaware district court’s decision of patent unenforceable
for inequitable conduct.

This appeal is with respect to US 9,283,197 patent (expiring on Aug. 15, 2034) assigned to Belcher Pharmaceuticals LLC. The patent describes the problem of l-epinephrine’s degradation and provides solution by finding suitable pH of 2.8 to 3.3. Hospira submitted NDA to the FDA seeking approval of a 0.1 mg/mL injectable l-epinephrine formulation and provided P-IV certification to US’197 patent. On June 16, 2017, Belcher sued Hospira for infringement. On March 31, 2020, the district court decided, among other things, that the ’197 patent is unenforceable for inequitable conduct based on Stepensky art and Sintetica’s prior epinephrine product. You can read the detailed summary “here“.

On appeal, Federal Circuit said that 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. With respect to materiality, Court said that Belcher does not challenge the district court’s decision that the asserted claims are invalid as obvious based on, inter alia, JHP’s epinephrine product, testing of which showed the product had a pH within the claimed range. Because that is the case, the product is “necessarily material to patentability.” With respect to intent, Court said that Mr. Rubin from Belcher was an active participant in the FDA approval process and understood that Belcher had stated to the FDA that the 2.8 to 3.3 pH range was an “old” range based on prior product/art. But, during prosecution Mr. Rubin emphatically and repeatedly advanced the position that the 2.8 to 3.3 pH range was a “critical” innovation and yielded “unexpected results,” namely reducing racemization of l-epinephrine. Therefore, Mr. Rubin’s withheld of the prior art, including the JHP product, that disclosed the pH range of 2.8 to 3.3. Thus, district court correctly found that the single most reasonable inference is that Mr. Rubin possessed the specific intent to deceive the PTO when withholding the JHP product. Hence, US’197 patent is unenforceable for inequitable conduct.