Docket No. 2014-1799, 2014-1800
LOURIE, TARANTO, HUGHES
May 21, 2015
Brief Summary: DC decisions regarding obviousness (“rivastigmine was not known to be susceptible to oxidative degradation at the time of the invention”) and non-infringment (“Novartis failed to put forth sufficient evidence that acetaldehyde [present in impurities in Par’s adhesive] is an antioxidant”) affirmed.
Summary: Watson appealed DC finding that the claims of Novartis’ US 6,316,023 and 6,335,031 relating to rivastigmine for treatment of dementia are not invalid as obvious. Novartis appealed DC decision that these patents are not infringed by Par Pharmaceutical’s generic product (the subject of its ANDA). The FC heard the appeals together as the same patents and parties, and related issues, are involved (the DC heard separate bench trials). Novartis was originally approved to market a transdermal patch in rivastigmine dosage amounts of 4.6 mg and 9.5 mg/24 hours, and later approved for 13.3 mg/24 hours. Par and Watson filed ANDAs covering these dosages and Novartis filed suit against both. Par filed suit against Novartis, seeking DJ that its 13.3 mg dose does not infringe the ‘023 patent. The asserted claims relate to a transdermal device for administering and methods for stabilizing rivastigmine, both types of claims referring to an “antioxidant” that was defined by the DC as an “agent that reduces oxidative degradation” (not disputed here). At Watson’s trial, the DC found that Novartis had proved infringement and Watson had not proved invalidity (“rivastigmine was not known to be susceptible to oxidative degradation at the time of the invention…the compatibility of excipients like antioxidants in a given formulation is unpredictable without experimentation…many known types of degradation other than oxidation, and one of skill in the art would only have been motivated to address known degradation problems…[prior art] was ‘silent with respect to rivastigmine’s instability” (citing Mintz, FC 2012 (“Often the inventive contribution lies in defining the problem in a new revelatory way.”) and Leo Pharm., FC 2013 (invention not obvious because skilled artisans “would not have recognized the problem”)). In the Par trial, Novartis alleged “that the acetaldehyde impurities found in the adhesive used in [the] ANDA product met the claimed antioxidant limitation, but the court found that Novartis failed to put forth sufficient evidence that acetaldehyde is an antioxidant”, crediting Par’s expert testimony that “one of skill in the art would not have considered acetaldehyde to be an antioxidant, but that acetaldehyde could instead promote oxidative degradation” and discounted Novartis’ expert testimony (“Experts for both parties agreed that not all reducing agents are antioxidants; simply because a reducing agent can reduce oxidative degradation does not necessarily mean that it actually does…Novartis failed to prove that acetaldehyde reduces oxidative degradation.”) The FC concluded the DC “did not clearly err in finding Par’s ANDA product was not shown to infringe any asserted claim containing the antioxidant limitation”. Both DC decisions were affirmed.