Cephalon, Inc. v. Watson Pharms., Inc., No. 2011-1325 (Fed. Cir. 2013)
In Cephalon v. Watson, decided earlier this month, the Federal Circuit reversed a finding of invalidity for lack of enablement where the factual record of undue experimentation was insufficient. The patented invention involved methods of oral mucosal administration of fenatanyl with tablets including effervescent agents used as penetration enhancers. The effervescent agents evolve gas as a result of exposure to a soluble acid source. The district court's claim construction of "agent" required that the dosage forms of the soluble acid source and the effervescent agent be separate but co-administered.
At trial before Judge Robinson in the District of Delaware, Watson succeeded in proving the asserted patents (U.S. Pat. Nos. 6,200,604 and 6,974,590) were invalid for lack of enablement. Watson's expert witness provided testimony that co-administration would be "difficult" and "complicated." The district court found further support for those opinions in Cephalon’s expert testimony regarding the need for experimentation.
The Federal Circuit initially corrected the district court's determination that Watson's prima facie case of lack of enablement was not rebutted by Cephalon and stated that "there is no formal burden-shifting framework when addressing the issue of enablement." The court found that, despite the district court's credibility finding, the largely unsupported testimony of Watson's expert "carries little weight in this analysis." The court also found, contrary to the district court, that Cephalon's expert testimony regarding the need for routine experimentation did not support the unsubstantiated opinions of Watson's expert. Specifically, the Federal Circuit found that Watson failed to show how much experimentation would be required for co-administration and that such experimentation would be excessive, particularly where the specification provided at least some guidance.
Notably, Watson's expert witness did not specifically analyze the Wands factors at trial. However, the Federal Circuit explained that such an analysis was not required for Watson to carry its burden, and the record lacked evidence of undue experimentation even assuming the district court's cursory consideration of the Wands factors was accurate.
Despite the Federal Circuit's reversal of the invalidity holding, Watson still prevailed, as the Federal Circuit affirmed the district court's holding of noninfringement.