The patent at issue is directed to a method of treating non-small cell lung cancer (NSCLC) by administering erlotinib, a compound that inhibits the epidermal growth factor receptor (EGFR). The patentability of several of the patent claims were challenged in an inter partes review petition, which the Board instituted. The Board ultimately found the challenged claims obvious over two prior art combinations. According to the Board, the combination of prior art references Schnur and Gibbs or Schnur and Patent Owner’s Form 10-K rendered the claims obvious.
On appeal, the Federal Circuit reversed, concluding that the Board’s finding of a “reasonable expectation of success” was not supported by substantial evidence.
As an initial matter, the court held that the Board misinterpreted one of the asserted references, Gibbs, when it found that Gibbs disclosed a “clear inference” that “erlotinib has anti-cancer activity against [NSCLC].” In reaching its decision, the court faulted the Board for failing to carefully consider the two internal references cited in Gibbs to support the statement in Gibbs that compounds have anti-cancer activity in patients with NSCLC. Only one of the two references even mentions NSCLC, but it does not mention erlotinib at all. Thus, properly “[r]eading Gibbs in the context of its cited articles,” the court explained, “reveals that this statement cannot be referring to erlotinib.” The court also faulted the Board for not properly considering a declaration submitted by Dr. Gibbs himself stating he was not aware of a publication discussing erlotinib’s effect on NSCLC at the time Gibbs was published.
Next, the court addressed the Board’s finding that the asserted combinations would have provided a person of ordinary skill with a reasonable expectation of success in using erlotinib to treat NSCLC. In rejecting that determination, the court pointed out that the asserted references “contain no data or other promising information regarding erlotinib’s efficacy in treating NSCLC.” Specifically, the court found that while Schnur broadly discloses over a hundred compounds for treating 12 different types of cancer, it “fails to disclose any in vitro or in vivo efficacy data for erlotinib or otherwise suggest the use of erlotinib to treat NSCLC.” The court further noted that Gibbs fails to cure these deficiencies because it only discloses that erlotinib inhibits the EGFR and has good anti-cancer activity only in certain cancers, not including NSCLC. Regarding Patent Owner’s Form 10-K, the court explained that although the 10-K states that erlotinib had completed Phase I clinical trials, “nothing in [Patent Owner’s] 10-K suggest[s] the existence of erlotinib preclinical efficacy data that is specific to NSCLC.” Finally, given the undisputed fact that NSCLC is highly unpredictable with an over 99.5 percent failure rate for drugs entering Phase II clinical studies, the court concluded that the asserted references “provide no more than hope—and hope that a potentially promising drug will treat a particular cancer is not enough to create a reasonable expectation of success.”
OSI Pharms., LLC v. Apotex Inc., No. 2018-1925, slip op. (Fed. Cir. Oct. 4, 2019)
Practice Tip: In defending against an obviousness challenge to method of treatment claims reciting efficacy, a patent owner should carefully assess whether the asserted references provide any in vitro or in vivo data showing the claimed method is efficacious. If the references lack efficacy data, the patent owner should point to that omission in arguing no “reasonable expectation of success.” A patent owner should also consider bolstering its argument by submitting evidence of clinical trial failures to show the unpredictability of the claimed treatment method.