Valeant Pharmaceuticals International, Inc. v. Mylan Pharmaceuticals Inc., No. 18-2097 (Fed. Cir. 2020)Annotate this Case
Valeant’s patent claims stable methylnaltrexone pharmaceutical preparations; methylnaltrexone, a quaternary amine opioid antagonist derivative, can be useful for reducing the side effects of opioids but is unstable in aqueous solution. The inventors discovered that when the pH of a methylnaltrexone solution is adjusted, the percentage of total degradants drops significantly. The patent is listed in the Orange Book for Relistor®, an injectable drug used to treat constipation as a side effect of taking opioid medication. Mylan filed an Abbreviated New Drug Application seeking FDA approval to market a generic version of Relistor®. Mylan conceded that its ANDA product would infringe claim 8 of the patent.
The district court entered the parties’ stipulation to the construction of claim 8’s stability limitation: the phrase “the preparation is stable to storage for 24 months at about room temperature” means “the methylnaltrexone degradation products in the preparation do not exceed 2.0% of the total methylnaltrexone present in the preparation and the preparation is suitable for pharmaceutical use when stored for 24 months at room temperature” and granted summary judgment that claim 8 would not have been obvious. The court rejected Mylan’s expert testimony and cited references and Mylan’s theory that the claimed pH range would have been obvious to try.
The Federal Circuit reversed. Mylar raised at least a prima facie case of obviousness. The district court’s obvious-to-try analysis is inconsistent with precedent.