In re Kao

May 26, 2011 – Blog Post

In re Kao, ___ F.3d ___ (Fed. Cir. 2011) (Appeal 2010-1307 from BPAI decision in U.S. Application Serial No. 11/680,432; Appeal 2010-1308 in Serial No. 12/167,859; and Appeal 2010-1309 in Serial No. 11/766,740), pertains to a group of three appealed cases from the BPAI following the BPAI’s affirmations of the Examiners’ conclusions of obviousness in these applications directed to controlled-release tablets containing oxymorphone.

The claims at issue were (A) in the ’432 application, oxymorphone tablet formulation of a particular dissolution rate, (B) in the ’859 application, a method of treatment over at least 12 hours, wherein the bioavailability is higher in a fed subject versus a fasting subject, and (B) in the ’740 application, a method of extended pain relief comprising informing a subject that the improved effect of administration with food.

The Examiner’s obviousness rejections primarily relied on WO 2001/008661 (Maloney), which disclosed controlled-release opioid (oxycodone) formulations. During prosecution and in response to those obviousness rejections, the Applicant submitted declarations:

  • explaining that the dissolution profile of the claimed oxymorphone and Maloney’s oxycodone (differing only in a methylation of the 9-OH group) formulations give markedly different bioavailability which was not obvious;
  • explaining that the controlled release of claimed morphone formulations show unexpected results - multiple peaks in oxymorphone blood concentration, which decrease the likelihood of tolerance development; and
  • showing evidence of commercial success of one marketed embodiment, Opana® ER.

In the ’432 application, the Examiner nonetheless concluded that the declarations were insufficient to show that Maloney did not suggest the claimed dissolution profile. Furthermore, the Examiner found that the evidence of unexpected results and commercial success were not commensurate with the scope of the claims, as these results were only shown for one embodiment, i.e. Opana® ER. The BPAI affirmed each of the Examiner’s positions, further relying on Maloney’s identification of oxymorphone as a preferred opioid.

In the ’859 application, the Examiner rejected the method of treatment as obvious since all elements of the formulation were generally disclosed for a formulation with oxycodone in Maloney. The BPAI affirmed the Examiner’s rejection and found that the declarations rebutted obviousness only for the single embodiment shown.

In the ’740 application, the BPAI also affirmed the Examiner as the correlation of renal impairment and bioavailability of oxymorphone while perhaps not previously known, was held to be inherent

The Federal Circuit reversed the BPAI’s ruling in the ’432 application, and upheld the BPAI’s rulings in the ’859 and ’740 applications. The Federal Circuit stated that, even if it would be obvious to substitute oxymorphone in Maloney’s formula, there was no direct evidence that the dissolution range claimed actually overlapped with Maloney’s, and thus it was irrelevant whether the skilled artisan would have appreciated the relationship of the dissolution methods, but whether there was anything to prompt the skilled artisan to in fact modify Maloney to be within the claimed scope. Further, the Federal Circuit held that the BPAI’s finding of a correlation between Maloney’s dissolution method and the claimed method, contrary to the content of the declarations, was unsupported.

Perhaps the most interesting aspect of this decision is the Federal Circuit’s discussion of the evidence of unexpected and commercial success that led to the Court’s decision to remand back to the BPAI for further consideration. Notably, the Federal Circuit ruled that although the evidence of secondary considerations “must be reasonably commensurate with the scope of the claims” (citing In re Tiffin, 448 F.2d 791, 792 (CCPA 1971); In re Hiniker, 150 F.3d 1369 (Fed. Cir. 1986)), this does not mean that an applicant is required to test every embodiment within the scope of the claims, as long as a nexus is established between the evidence and the merits of the claimed invention (citing Wyers v. Master Lock Co., 616 F.3d 1231, 1246 (Fed. Cir. 2010)). Where the unexpected result or commercial success is due to an element in the prior art, no nexus exists. Recall that the Examiner and the Board maintained the rejections based on the theory that the evidence was not commensurate in scope with the invention. Thus, the Federal Circuit ruled that the BPAI did not give adequate weight to the secondary considerations across all claimed embodiments, so as to determine whether the commercial success or unexpected results resulted from the merits of the claimed invention as opposed to the prior art or other extrinsic factors.

This is not new law and indeed follows years of Federal Circuit precedent and previous BPAI decisions. See, for example, In re Kollman 595 F.2d 48, 201 USPQ 193 (Fed. Cir. 1979): (“We feel that the unobviousness of a broader claimed range can, in certain instances, be proven by a narrower range of data. Often, one having ordinary skill in the art may be able to ascertain a trend in the exemplified data which would allow him to reasonably extend the probative value thereof. The proof, thus considered, might then be sufficient to rebut a PTO holding of prima facie obviousness. 595 F.2d at 56, 201 USPQ at 199, and Ex parte Winters, 11 USPQ2d 1387, 1388 (Bd. App. & Inter. 1989).

Although the Federal Circuit found that the BPAI and Examiner had not adequately evaluated these secondary considerations in the case of the ’859 and ’740 applications, such secondary considerations were nonetheless insufficient to rebut the stronger cases of obviousness in those applications. Even so, evidence rather than just arguments should be considered if you are going to appeal similarly situated applications if you want the BPAI and, perhaps the Federal Circuit, to decide in your favor.