Docket No. 2015-2095
PROST, DYK, STOLL (D)
May 3, 2017
Brief Summary: DC grant of SJ to PTO that claims to NK cell immunotherapy would have been obvious affirmed (“no material dispute that the combination…used here produced the invention and that persons of ordinary skill would have been motivated to combine” the references). Judge Stoll’s dissent argued SJ should not have been granted due in part to NantKwest’s expert testimony.
Summary: Assignee NantKwest appealed PTO rejection (affirmed by the Board) of claims 20, 26 and 27 of U.S. Ser. No. 10/008,955 directed to methods for treating cancer using a natural killer cell line (“wherein said cancer is recognized and lysed by said NK-92 cell line”) as obvious in view of “Santoli’s” (US 5,272,082) disclosure of a T cell line (TALL-104) for treating cancer in vivo (adoptive T cell immunotherapy) and “Gong’s” disclosure (including the patent applicant Hans Klingemann) that “NK-92 can lyse cancer cells in vitro with high efficacy.” NantKwest appealed the Board’s decision to the DC which granted the PTO’s motion for SJ. NantKwest argued there were disputes of factual issues that could not be resolved on SJ, but the DC disagreed and NantKwest appealed. The FC panel explained that it reviews the grant or denial of SJ de novo (MicroStrategy, FC 2005), and “claim construction…de novo where, as here, there is no relevant extrinsic evidence” (Teva, US 2015). And obviousness is found “if ‘a skilled artisan would have been motivated to combine the teachings of the prior art references to achieve the claimed invention” with “a reasonable expectation of success in doing so” (Proctor & Gamble, FC 2009). NantKwest argued the DC’s claim construction was incorrect but the FC panel found this not to be a “basis for reversal” since it was “harmless error” (i.e., obviousness still found under the correct construction). The FC panel agreed with the DC “that there is no material dispute that the combination…used here produced the invention and that persons of ordinary skill would have been motivated to combine” the references (e.g., “Prior art publications by the patent applicant himself indicated that there was a motivation to seek clinical applications for the NK-92 cell line” and “the ‘955 application itself referred to Gong to describe the superior qualities of the NK-92 cell line.”) And another prior art reference (“Yan”) showed a head-to-head test of TALL-104 and NK-92 and concluded the in vitro efficacy of NK-92 was even greater than” that of TALL-104. FN2 explains “[t]he alleged post-filing failure of TALL-104 therapy in human clinical trials-not known at the time of the application-is irrelevant” (In re Vaeck, FC 1991 (“[E]xpectation of success must be founded in the prior art.”)) The FC panel also found “that it would have been at least obvious…to try to combine the teachings” (KSR, US 2007 (“finite number of identified, predictable solutions” with “anticipated success”)). It explained that “the only situations” where obvious-to-try “does not apply is where ‘the inventor would have had to try all possibilities in a field unreduced by direction of the prior art…[or] where vague prior art does not guide an inventor toward a particular solution” (Bayer, FC 2009). Regarding NantKwest’s proferred expert opinion, the FC panel explained that its “cases hold that whether the skilled artisan can extrapolate in vivo success from in vitro results in highly fact-specific” (In re Gangadharam, FC 1989; In re Carrol, CCPA 1979) and “[o]bviousness cannot be avoided simply by a showing of some degree of unpredictability” (Pfizer, FC 2007). It concluded that “here…there is overwhelming specific evidence that a skilled artisan could reasonable extrapolate from the in vitro data” and there was no evidence of teaching away. And it was not convinced NantKwest’s secondary considerations had the requisite nexus to the claims (a $48 million investment) or were unexpected (clinical results). Thus, the DC grant of SJ was granted. Judge Stoll’s dissent argued SJ should not have been granted due in part to NantKwest’s expert testimony.