Eisai Wins One Summary Judgment Motion and Part of Another in Aciphex Suits Against Teva and Dr. Reddy's
As we previously reported in brief, Eisai recently won summary judgment of patent validity of U.S. Patent No. 5,045,552 in its lawsuit against Teva over generic Aciphex (rabeprazole sodium). In a separate opinion handed down the same day, the court also denied in part and granted in part Eisai's motion for summary judgment of no inequitable conduct. The latter opinion relates both to Teva and Dr. Reddy's, as both defendants asserted unenforceability of the '552 patent. Aciphex is a proton pump inhibitor and, with annual sales of about $1.2 billion last year, it accounts for over 40% of Eisai's total U.S.drug sales.
In the opinion on Eisai's motion for summary judgment of patent validity, Judge Gerard E. Lynch of the U.S. District Court for the Southern District of New York held that the claims of the '552 patent would not have been obvious because there was no teaching, suggestion, or motivation to combine three prior art references asserted by Teva. According to Judge Lynch, the non-obvious step was the selection of the lead compound in the first place:
While obviousness analysis is a totality-of-evidence inquiry, it is unnecessary to this decision to discuss each step of the combination Teva has proposed. The inadequacy of proof as to one key step alone suffices to negate the possibility of ultimately persuading a reasonable fact finder on the stated standard. That step is the incorporation of lansoprazole as the conceptual foundation of the asserted combination.
Judge Lynch reviewed Teva's arguments that one of ordinary skill in the art would have selected lansoprazole as the lead compound to ultimately produce rabeprazole, and concluded as follows:
Nothing about these teachings requires or even suggests the use of . . . lansoprazole as a lead compound. Rather, [Teva] offers these teachings solely to explain modifications that would have been performed once lansoprazole was selected. . . . Expert testimony of a “good” or “reasonable” starting point is not sufficient to permit a finding by clear and convincing evidence that this combination is not just attractive in hindsight, but rather would have been made at the relevant time. Without persuasive evidence of lansoprazole’s place in the pattern, [Teva’s] asserted combination falls apart.
Only Teva asserted the patent invalidity defense. Dr. Reddy's had stipulated to the validity of the '552 patent.
In the opinion on Eisai's motion for summary judgment of no inequitable conduct, Judge Lynch reviewed the prosecution file histories of the '552 patent and a related U.S. patent application, "the '013 application." The court concluded that there were genuine issues of fact requiring a trier of fact to assess both materiality and intent in Eisai's failure to disclose the co-pendency of the '013 application, which dealt with a homolog of rabeprazole, as well as Eisai's failure to disclose the patent office's rejections of certain claims in the '013 application. On the other hand, Judge Lynch also granted summary judgment of no inequitable conduct as to two other allegations made by Teva and Dr. Reddy's.
Eisai has also brought suit against Mylan over generic Aciphex (Civil Action No. 04-656 in the S.D.N.Y.). The suit against Mylan is stayed pending the results of the actions against Teva and Dr. Reddy’s. Mylan has stipulated to be bound by the final judgments and any appeals in the suits against Teva and Dr. Reddy’s.
