Complete Victory for Vifor Fresenius in Pharmaceutical Patent Litigation

Quinn Emanuel won a complete victory for its client Vifor Fresenius Medical Care Renal Pharma Ltd. in a pharmaceutical patent case against Teva Pharmaceuticals USA, Inc. As a result, Vifor Fresenius’s Velphoro® product will be protected from generic competition until July 2030.

The case arose from Teva’s seeking FDA approval to market a generic version of Vifor Fresenius’s Velphoro® product, which is a phosphate binder indicated for the treatment of hyperphosphatemia.  Vifor Fresenius asserted that Teva infringed U.S. Patent No. 9,561,251 (“the ’251 patent”), and Teva counterclaimed seeking declaratory judgments of non-infringement, invalidity, and unenforceability of the ’251 patent.  On August 18, 2022, the Honorable Maryellen Noreika (District of Delaware) concluded that Teva’s ANDA Product will infringe all asserted claims of the ’251 patent and also concluded that Teva failed to meet its burden to establish that any of the asserted claims were invalid as obvious or for lack of enablement. 

With respect to infringement, Teva first argued that Vifor Fresenius’s reliance on “statements in [Teva’s] proposed label” had not shown that Teva’s product is “essentially non-bioabsorbable” (claim 29) because the statements “were copied from the Velphoro package insert.” In finding for Vifor Fresenius, the Court credited Vifor Fresenius’s expert’s opinion that “the expectation that a generic drug behaves in the same manner as the branded drug is something that physicians rely upon when prescribing generic drugs.” The Court also found that “it strains credulity for Teva to argue that it has sought FDA approval without knowing whether its proposed package insert accurately describes its ANDA product (and without knowing whether its ANDA product could prove toxic to patients).” The Court similarly rejected Teva’s arguments that Vifor Fresenius failed to show that Teva’s product had “an iron release rate of below 2.5% w/w” (claim 30). The Court credited Vifor Fresenius’s expert, finding that “his observed pH range of 3.22 to 3.28 was ‘at a pH of 3’ to the whole number” and thus was “consistent with the Court’s claim construction based on mathematical rounding principles” and “supported by his unrebutted testimony regarding the purpose of the iron release test within the framework of the relevant art.”

For validity, the Court first found that Teva had failed to show that any of the asserted claims are invalid for obviousness. Noting that “this obviousness issue comes down to weighing competing facts – particularly competing expert testimony,” the Court explicitly “found Plaintiff’s experts to be more credible” than Teva’s experts and that “Defendant’s obviousness arguments suffer from significant and improper hindsight bias.”  The Court next found that Teva had failed to show that the “clinically significant” term of claim 29 was invalid for lack of enablement.  Here, the Court credited Plaintiff’s expert’s explanation “that clinical significance would be readily understood by a healthcare provider.” The Court disagreed with Teva that determining clinical significance would require testing “each and every individual patient”; again, the Court credited Plaintiff’s expert’s testimony that one would “look[] at patient population averages, not any individual outcomes.”

The Court entered a permanent injunction barring Teva from selling its proposed generic product until the ’251 patent and its six months’ pediatric exclusivity expires in July 2030.