In a recent post-trial opinion, Judge Sue L. Robinson considered infringement of U.S. Patent Nos. 6,200,604 (“the ’604 Patent”); 6,974,590 (“the ’590 Patent”); and 8,119,158 (“the ’158 Patent”), and the validity of U.S. Patent No. 8,092,832 (“the ’832 Patent”) and the ’158 Patent in this ANDA litigation. Cephalon Inc. et al. v. Mylan Pharmaceuticals Inc. et al., C.A. No. 11-164-SLR (D. Del. Jul. 22, 2013). Plaintiffs initiated this litigation after defendants filed ANDA No. 202577, which sought to market generic fentanyl citrate buccal tablets, a medication that aids breakthrough cancer pain. Id. at 1-2.
Before addressing infringement and validity, Judge Robinson was required to construe two disputed claim terms. “Providing a solid oral dosage form” was given its ordinary meaning, and “pH adjusting substance is not a component of said effervescent material” was construed to mean “pH adjusting substance is in addition to the components of said effervescent agent.” Id. at 13-18. Turning to the infringement of the asserted claims of the ’590 and ’604 Patents, Judge Robinson noted that the “only limitation of the asserted claims . . . that [defendants] argue is not met by the ANDA product ‘is at least one [salival activated] effervescent agent in an amount sufficient to increase absorption.’” Id. at 20. Judge Robinson ultimately determined that plaintiffs demonstrated that defendants’ ANDA practiced “each and every requirement of the disputed limitations.” Id. at 38. Further, there was no “genuine dispute of material fact that [defendants] will encourage use through its product labeling and sale of its generic tablets and is aware that the label presents infringement problems.” Id. at 37. Moreover, because “[t]he only authorized use for the ANDA products would infringe” the asserted claims, there was “no substantial noninfringing use.” Id. at 38. Judge Robinson thus concluded that defendants indirectly infringed the asserted claims of the ’590 and ’604 Patents through induced infringement and contributory infringement. Id. Next, Judge Robinson considered infringement of the ’158 Patent, noting that “[t]he only dispute for infringement is whether the ANDA products meet the limitation ‘wherein said pH adjusting substance is not a component of said effervescent material.’” Id. Defendants did “not offer any noninfringement defense under the court’s construction” of that limitation, and Judge Robinson concluded that defendants directly and indirectly infringed the ’158 Patent. Id. at 39-40.
Judge Robinson next considered whether the ’604 Patent anticipated certain asserted claims of the ’92,832 and ’158 Patents. Judge Robinson noted that those claims required dosages between 100 and 800 mcg of fentanyl free base. Id. at 43. Defendants’ expert argued that a “person of ordinary skill in the art would understand a ‘pharmaceutically effective amount’ taught by the ’604 Patent includes fentanyl free base in the range of 100 to 800 mcg,” because a person of ordinary skill in the art would have would have looked at “Actiq®, an FDA-approved product and recognized that its range of fentanyl, 200-1600 mcg, was pharmaceutically effective.” Id. at 43-44. Judge Robinson noted, however, that “extrinsic evidence of anticipation ‘must make clear that the missing descriptive matter is necessarily present in the thing described in the reference.’” Id. at 44. As Judge Robinson explained, Actiq® was “not mentioned in the ’604 patent or incorporated therein.” Id. Because Judge Robinson found that the “’604 patent does not disclose the claimed amounts of fentanyl, the [’92,832 and ’158 Patents] are not invalid for anticipation.” Id. at 43.
Judge Robinson also considered whether the asserted claims of the ’92,832 and ’158 Patents were obvious “in view of the ’604 patent in combination with the Actiq® brochure and the Handbook.” Id. at 45. Judge Robinson noted that defendants’ expert did “not offer an opinion that one of ordinary skill in the art, absent the benefit of . . . internal observations and documents, would have had any reasons to suspect stability issues, and therefore, be motivated to solve such issues. He cannot rely on the problems that the inventors ‘unexpected[ly]’ ran into in order to support a person of ordinary skill’s motivation to combine.” Id. at 51. Because defendants did not provide sufficient evidence of motivation to use “SSG, alone or combination with mannitol,” defendants failed to carry its burden of showing obviousness. Id. at 53. Judge Robinson additionally assessed secondary considerations of nonobviousness. Judge Robinson found “unexpected results . . . sufficiently supported by [plaintiffs’] testing,” which weighed in favor of nonobviousness. Id. at 53-56. On the other hand, Judge Robinson found that considerations of commercial success, praise, failure of others, and long-felt need did not weigh in favor of a finding of nonobviousness. Id. at 56-61. However, on balance, Judge Robinson concluded that defendants failed to demonstrate by clear and convincing evidence that the asserted claims of the ’92,832 and ’158 Patents were obvious in light of the prior art references. Id. at 61.