Apotex Prevails Over Daiichi Sankyo in Floxin Otic Case, as Federal Circuit Invalidates Daiichi's Patent
Daiichi Sankyo Co. v. Apotex, No. 2006-1564 (Fed. Cir. 2007)
In a nonprecedential opinion released today, the Federal Circuit reversed a district court decision that held Daiichi Sankyo's U.S. Patent No. 5,401,741 not invalid for obviousness. The '741 patent claims a method for treating bacterial ear infections by topically administering the antibiotic ofloxacin (marketed by Daiichi as Floxin Otic solution, 0.3%). Apotex had filed an ANDA for generic Floxin Otic, certifying under Paragraph IV that the '741 patent is invalid. The FDA tentatively approved Apotex's ANDA in November 2005.
The Federal Circuit's decision turned on its finding of clear error in the district court's determination of the level of ordinary skill in the art, one of the Graham factors. The district court had concluded that the ordinary person skilled in the art pertaining to the '741 patent would be "a pediatrician or general practitioner--those doctors who are often the 'first line of defense' in treating ear infections." The Federal Circuit observed that in their briefs to the district court, the parties had provided little more than conclusory arguments, and therefore the district court "looked to other decisions involving patents for a method of treating a physical condition for guidance." According to the Federal Circuit, the district court's reliance on those decisions was improper.
The Federal Circuit suggested that the district court should have made its own factual findings regarding the level of skill in the art. For instance, according to the Federal Circuit, "the inventors of the '741 patent were specialists in drug and ear treatments--not general practitioners or pediatricians;" "others working in the same field as the inventors of the '741 patent were of the same skill level;" and "while a general practitioner or pediatrician could (and would) prescribe the invention of the '741 patent to treat ear infections, he would not have the training or knowledge to develop the claimed compound absent some specialty training such as that possessed by the '741 patent's inventors."
The level of skill in the art matters in this case because Daiichi succeeded in convincing the district court that a key prior art reference, "Ganz," disclosed "nothing at all" relevant because it was directed at "a highly, highly subspecialized physician . . . which would be the otologist or the ear doctor," not a primary care physician or general practitioner. The Federal Circuit concluded, "Daiichi's evidence as to why this reference did not render the invention of the '741 patent obvious was based on an improper determination of the level of skill in the art," and therefore reversed the district court's validity finding.
RELATED READING:
Comments