Last month, in In re Efthymiopoulos, the Federal Circuit affirmed the determination by the U.S. Patent and Trademark Office Patent Trial and Appeal Board affirming the Examiner's rejection of all pending claims of Appellant Constantin Efthymiopoulos's U.S. Patent Application No. 08/737,141 as being obvious. The '141 application relates to methods of treating or preventing influenza by administering the drug zanamivir by oral inhalation. Claim 14 is representative:
14. A method for treating a human suffering from an infection by an influenza virus, wherein the method comprises administering to the human an effective amount of 5-acetamido-2,3,4,5-tetradeoxy-4-guanidino-D-glycero-D-galacto-non-2-enopyranosonic acid, wherein the 5-acetamido-2,3,4,5-tetradeoxy-4-guanidino-D-glycero-D-galacto-non-2-enopyranosonic acid is administered by inhalation through the mouth alone.
5-acetamido-2,3,4,5-tetradeoxy-4-guanidino-D-glycero-D-galacto-non-2-enopyranosonic acid is the chemical name for zanamivir.
During prosecution of the '141 application, the Examiner rejected the pending claims as being obvious in view of Australian Patent No. AU-A1-27242/92 ("Von Itzstein II"), in view of International Publication No. WO 91/16320 ("Von Itzstein I") and several other references. Von Itzstein I discloses intranasal administration, but not oral inhalation, of zanamivir, and Von Itzstein II discloses administration of a compound similar to zanamivir by "inhalation" for the treatment and prevention of influenza. The Examiner determined that (1) zanamivir and the compound disclosed in Von Itzstein II were similar enough that it would have been obvious to use zanamivir in the method of Von Itzstein II; (2) even though Von Itzstein II did not teach oral inhalation, there are only two possible inhalation methods (i.e., oral and nasal); and (3) other prior art references taught inhalers, that oral inhalation delivers more drug to the lungs than nasal inhalation, and that influenza infects the lungs. The Examiner therefore concluded that it would have been obvious to treat influenza by oral inhalation of zanamivir. The Board affirmed the Examiner's rejections and found Appellant's evidence of secondary considerations (i.e., unexpected results) to be unpersuasive.
In an opinion authored by Chief Judge Prost and joined by Judge Bryson, with Judge Newman dissenting, the Federal Circuit concluded that the Board did not err in affirming the Examiner's rejection of Appellant's claims. In particular, the majority opinion states that:
There is also no dispute that Von Itzstein II discloses several pages of different administration methods for an adjacent homologue of zanamivir to achieve the same result—treating or preventing influenza. In particular, Von Itzstein II expressly discloses administration through "oral," "nasal," or other forms "suitable for administration by inhalation," among other methodologies.
The majority opinion also points out that the Board "agreed with the examiner's conclusion that Von Itzstein II's disclosure of administration through 'inhalation' includes oral inhalation," and that the Board had indicated that:
[I]nhalation can only be carried out via the nose or the mouth. Since Von Itzstein II does not limit its disclosure to nasal inhalation, it is reasonably understood to disclose inhalation by either the nose alone, the mouth alone, or both.
As for Appellant's evidence of unexpected results, the majority opinion states that "[t]he record shows that the Board thoroughly considered and discussed [Appellant's expert] Dr. Hayden's declaration in its decision and found that Dr. Hayden's testimony insufficient to overcome the prima facie case of obviousness." The majority opinion therefore affirmed the Board's decision affirming the Examiner's rejection of the pending claims of the '141 application.
In a dissenting opinion, Judge Newman writes that:
The PTAB and now this court rule that it was obvious to administer this drug by oral inhalation, although there is no reference, no prior art, no suggestion, proposing that this mode of application might succeed, or that it should be tried. There was evidence of skepticism even as oral inhalation was evaluated. There was no contrary evidence. The evidence on which the Board and now this court rely is the evidence in the patent application itself, describing oral inhalation, its benefits, and its effectiveness. Upon learning this information from this inventor's disclosure, the Board found that it was obvious, and my colleagues agree that it is obvious to them.
Judge Newman points out that both the Board and the Examiner recognized that Von Itzstein II does not specifically teach inhalation of zanamivir through the mouth, adding that:
Nor does any other reference teach or suggest treatment of influenza by oral inhalation of this compound or any related compound. My colleagues nonetheless deem this treatment of influenza obvious on the ground that inhalation occurs only through the nose or the mouth. Thus the court rules that the discovery of effective treatment by oral inhalation is obvious to the court, although not obvious to experts, and not suggested in the prior art.
As for the teachings of Von Itzstein II, Judge Newman notes that "there is extensive discussion in Von Itzstein II directed to all of the known forms of oral administration of this product—plus parenteral, topical, rectal, vaginal, and intranasal administration—but Von Itzstein II lacks any mention of oral inhalation," adding that "[t]he description of suitable formulations continues for almost three more pages, but does not mention or suggest oral inhalation." Judge Newman also asserts that "[t]he Board's statement that inhalation is 'reasonably understood' to include oral inhalation is without authority," explaining that "[t]here was no record showing or supporting such an understanding," and that "[t]his mode of therapy is taught only by this inventor." Judge Newman therefore concluded that "[t]here was not substantial evidence to support the Board's ruling of obviousness."
In re Efthymiopoulos (Fed. Cir. 2016)
Panel: Chief Judge Prost and Circuit Judges Newman and Bryson
Opinion by Chief Judge Prost; dissenting opinion by Circuit Judge Newman
