Teva v astrazeneca invalidating a patent with secret prior art
At trial, Cadence and Pharmatop successfully proved by a preponderance of the evidence that Exela's generic version of OFIRMEV® literally infringed all ten asserted claims of the '222 patent.
Despite Exela's arguments to the contrary, the plaintiffs successfully proved that in Exela's generic product, sodium ascorbate acted as a "buffering agent" and mannitol acted as a "free radical scavenger" (i.e., an antioxidant).
Because the Federal Circuit believed the prior art itself provided such motivation, the asserted claims were found to be obvious.
barring Exela from manufacturing a generic version of OFIRMEV®, which is an injectable liquid acetaminophen composition. In 2011, Cadence and Pharmatop sued Exela Pharma Sciences, LLC, Exela Pharmsci, Inc., and Exela Holdings, Inc.
The district court construed the term “alkaline salt” and “pharmaceutically acceptable salt” to be limited to the disclosed salts. Based upon a certification from the Defendant that it would not manufacture below 0.3%, the District Court granted summary judgment of non-infringement.
After this ruling, the parties consented to a final judgment that Hanmi’s proposed product does not infringe the claims of either of the asserted patents. What Reddy has asked the FDA to approve as a regulatory matter is the subject matter that determines whether infringement will occur, and the fact that Reddy either tells the court that its manufacturing guidelines will keep it outside the scope of the claims or has even filed a declaration in the court stating that it will stay outside the scope of the claims does not overcome the basic fact that it has asked the FDA to approve, and hopes to receive from the FDA, approval to market a product within the scope of the issued claims.
The court was unconvinced by Exela's argument for two reasons.
First, the court found independent claim 1 was valid and nonobvious given the technical differences in degradation of paracetamol compared to the degradation of pyrogallol (hydrolysis instead of oxidation), as well as the technical difficulties of deoxygenation.
The Court reversed as to the other claims, concluding they would have been obvious to one of skill in the art. The case turned on whether one of skill would have been motivated to combine the teachings of the prior art to derive the claimed subject matter.This meant that Exela's generic product met each of the asserted claim limitations.Although Cadence and Pharmatop failed to prove literal infringement of any of the four asserted claims of the '218 patent, the plaintiffs succeeded under the doctrine of equivalents. 5,270,050—rendered the '222 patent anticipated or obvious. Cadence is a Delaware corporation based in California that has an exclusive license to the '222 and '218 patents. Plaintiff SCR Pharmatop ("Pharmatop") is a French civil law partnership that owns U. Paracetamol is the name used outside of the United States for acetaminophen.
Two other cases resulted in non-infringement findings and one was a mixed result. The Federal Circuit remanded the case to the District Court to allow the Court to evaluate the merits in light of the correct claim construction and affirmed the District Court’s obviousness determination.