Experimental Use Cannot Negate Public Use If the Invention has been Reduced to Practice before the Experimental Use

ASTRAZENECA AB, v. APOTEX CORP., APOTEX, INC., [2007-1414, -1416, -1458, -1459] (August 20, 2008) [BRYSON, Lourie,GAJARSA] The Federal Circuit affirmed judgments of infringement against Apotex and Impax in litigation involving a number of generic drug manufacturers for infringement of Astra’s patents covering formulations of omeprazole, the active ingredient in Prilosec, a drug designed to treat acid-related gastrointestinal disorders.
DISCUSSION: Impax argumed that the district court lost jurisdiction over the case after the patents expired. The district court rejected that argument because the FDA had granted Astra an additional six-month period of market exclusivity after Astra had agreed to the FDA’s request that it perform pediatric testing of its product. The Federal Circuit found that the district court correctly interpreted section 271(e)(4)(A) to provide a post-expiration remedy for infringement under section 271(e)(2).
Impax challenged the district court’s finding that Impax’s formulation met the “inert subcoating” limitation of both patents. The Federal Circuit noted that Astra did not need to identify the process by which the infringing subcoating was produced; it was sufficient for it to show the presence of the claimed structure. The Federal Circuit found sufficient evidence to support the existence of the required inert subcoating.
Regarding Impax’s challege to the validity, before the critical date Astra commissioned four large clinical studies to determine the safety and efficacy of its formulation in order to obtain FDA approval. The district court ruled that the studies constituted experimental uses, not public uses, of the claimed invention. The district court further ruled that the patented formulation was not ready for patenting until after the studies were completed. The Federal Circuit agreed that experimental use cannot negate a public use when it is shown that the invention was reduced to practice before the experimental use. However, the Federal Circuit said it could affirm affirm the district court’s conclusion that the claims were not invalid under section 102(b) based on the court’s factual determination that the claimed formulation was not ready for patenting until after the clinical studies were completed. The Federal Circuit said that the district court found that the claimed formulation was not reduced to practice before the clinical trials were completed, and upheld that finding. The Federal Circuit noted that In Pfaff, the Supreme Court described two ways for a party to show that an invention was ready for patenting before the critical date of section 102(b): “by proof of reduction to practice before the critical date; or by proof that prior to the critical date the inventor had prepared drawings or other descriptions of the invention that were sufficiently specific to enable a person skilled in the art to practice the invention.” To demonstrate reduction to practice, the Federal Circuit said that a party must prove that the inventor (1) constructed an embodiment or performed a process that met all the limitations and (2) determined that the invention would work for its intended purpose. The Federal Circuit said that testing is required to demonstrate reduction to practice in some instances because without such testing there cannot be sufficient certainty that the invention will work for its intended purpose. The Federal Circuit said that the district court found that the Phase III formulation was not reduced to practice before the trials because the evidence showed that at that time the inventors believed only that the formulation “might solve the twin problems of in vivo stability and long-term storage” and the Federal Circuit agreed.
Turning to Apotex’s appeal, Appotex argued that its manufacturing process merely practices the prior art. However the Federal Circuit responded that it is well established that “practicing the prior art” is not a defense to infringement. Based on the district court’s thorough analysis of the prior art and the nature of the problem, the Federal Circuit found no error in the court’s findings of fact and conclusions of law on the question of obviousness.