Thursday, March 12, 2009

Obviousness in interferences; Chapman and the 14- hydroxy problem in oxycodone

The (nonprecedential) Chapman decision by the CAFC resolves an interference between Chapman et al.
and Casner et al., in favor of Casner. The subject matter pertains to the synthesis of the
drug oxycodone. An interesting aspect is that the panel majority and the dissent view
the obviousness inquiry here in entirely different ways, with only the dissent (who would find
NONOBVIOUSNESS as to Chapman) citing to KSR v. Teleflex.

Important text in the opinion, wherein the panel majority formulates the issue in terms
of species/genus-->

Regardless, we need not resolve the waiver issue definitively. Chapman
maintains, and we agree, that “[t]he term ‘8,14-dihydroxy’ properly includes 8α, but there
is no reason for that term to be limited to that isomer in Chapman’s claims. The term
‘conditions’ properly includes commercial conditions, but there is no reason to limit that
term to commercial conditions in Chapman’s claims.” Appellant’s Reply Br. 27. Further,
the ’897 application states: “The term 8,14-dihydroxy-7,8-dihydrocodeinone includes
either 8α,14-dihydroxy-7,8-dihydrocodeinone; or 8β,14-dihydroxy-7,8-dihydrocodeinone
or can include a mixture of both compounds.” ’897 application ¶ 0043.

Thus, claim 96 merely requires one to incubate the mixture “under conditions
suitable to promote reaction” of 8,14-dihydroxy to 14-hydroxy. Therefore, prior art
references that disclose either the 8α or 8β form of 8,14-dihydroxy converting to 14-
hydroxy, or disclose any reaction condition (whether “commercial” or not) that promotes
the conversion of 8α or 8β to 14-hydroxy, may render the claim obvious.
See In re May,
574 F.2d 1082, 1088–89 (C.C.P.A. 1978) (“[The reference] expressly discloses . . . a
species within the genus of claim 1. Therefore, [the reference] is a technical
anticipation of claim 1. Appellants’ assertions to the contrary notwithstanding, this
finding does not constitute a new ground of rejection; lack of novelty is the epitome of
obviousness.”); cf. Medichem, S.A. v. Rolabo, S.L., 353 F.3d 928, 934–35 (Fed. Cir.
2003) (concluding that first step of an interference-in-fact inquiry was satisfied where
two method claims had a genus/species relationship, since “‘[i]t is . . . an elementary
principle of patent law that when, as by a recitation of ranges or otherwise, a claim
covers several compositions, the claim is “anticipated” if one of them is in the prior art.’”
(quoting Titanium Metals Corp. v. Banner, 778 F.2d 775, 782 (Fed. Cir. 1985)); Eli Lilly
& Co. v. Barr Labs., Inc., 251 F.3d 955, 971 (Fed. Cir. 2001) (in context of an
obviousness-type double patenting analysis, noting that “[t]he only other difference
between [the two method claims] is that the former is directed to humans while the latter
is directed to animals,” and “[o]ur case law firmly establishes that a later genus claim
limitation is anticipated by, and therefore not patentably distinct from, an earlier species

[IPBiz notes that a rejection for obviousness is distinct from a rejection for anticipation.
One knows that something can be obvious, but not anticipated, AND it is also true something can
be anticipated but not obvious.]

Of obviousness-->

The Board found that the prior art discloses methods under which at least one
8,14-dihydroxy reacts to yield 14-hydroxy under certain conditions. Specifically, the
Board noted that the FDA “recognized that there was a need to eliminate impurities in
oxycodone,” and then proceeded to walk through the prior art, which disclosed: that
both 14-hydroxy and 8,14-dihydroxy were known impurities during the thebaine
oxidation reaction; that treatment of 8,14-dihydroxy with hydrochloric acid converts 8,14-
dihydroxy into 14-hydroxy under certain reaction conditions; that one of skill in the art
would be able to identify those conditions; and that 14-hydroxy may be removed from
oxycodone via hydrogenation.

As mentioned, claim 96 would have been obvious if properly-combinable
references disclosed conditions suitable to promote reaction of 8,14-dihydroxy to 14-
The prior art references here do just that: they indicate that 8β, at least, will
under certain reaction conditions form 14-hydroxy. Given that claims directed to the
genus (methods for eliminating 8,14-dihydroxys) can be anticipated or rendered obvious
by references disclosing the species (methods for eliminating either the 8α or 8β form of
8,14-dihydroxy), we agree with the Board that the method described in claim 96 would
have been obvious.

As a result, Robert Chapman, Lonn Rider, Qi Hong, Donald Kyle, and Robert Kupper
(“Chapman”) [represented by Darby & Darby] and U.S. Patent Application No. 11/391,897
(“the ’897 application”) lost.

Judge Rader dissented from the opinion of Judge Prost. Judge Rader viewed this in terms of
problem & solution:

The Food and Drug Administration seeks the removal of impurities such as 14-
hydroxy from the pain medicine oxycodone salt. During research on oxycodone,
Chapman discovered that oxidation of thebaine creates the stereoisomer 8α, which in
turn creates additional 14-hydroxy during formulation of this important pharmaceutical.
Until this discovery, this field of art believed that the original oxidation step created the
additional 14-hydroxy impurity. After discovering 8α, Chapman learned to isolate and
hydrogenate the additional 14-hydroxy to eliminate most of these impurities. Chapman,
thus, was the first person to identify the true nature of the “leftover” 14-hydroxy problem
and the first to solve it. Because this important and innovative solution deserves a
patent over the prior art, I would reverse the Board.

Judge Rader went back to the Eibel case:

Chapman’s invention calls to mind the Supreme Court’s resolution of Eibel
Process Co. v. Minnesota & Ontario Paper Co., 261 U.S. 45 (1923). In Eibel, the
primary distinction of the invention over the prior art was discovery of the problem in that
discipline. Id. at 67-68. (...) With the problem defined, Eibel easily prescribed the solution
by elevating one end of With the problem defined, Eibel easily prescribed the solution by elevating one end of
the paper feed to equalize the speeds of the wire and the paper stock by gravity.

Rader analogized the cases:

Chapman’s invention was not the mere use of a known technique to
remedy a known source of trouble, but was, as Chief Justice Taft stated, “the discovery
of the source not before known and the application of the remedy” for which he seeks
reward of the grant of a patent.

Rader brought up the Conover case:

Similarly, in In re Conover, Conover discovered a solution to the problem of
connecting a rod to an outboard motor engine containing compact, anti-friction roller
bearings. 304 F.2d 680, 681 (C.C.P.A. 1962).

Rader brought up Sponnoble, 405 F.2d 578, 586 (C.C.P.A. 1969):

The CCPA found, “a patentable invention may lie in the discovery of the source of a problem
even though the remedy may be obvious once the source of the problem is identified. (...) The court
reasoned that “[t]he question here is whether the prior art recognized the cause of the problem,”
which it did not. Id.

Rader cited Peehs, 612 F.2d 1287, 1290 (C.C.P.A 1980):

“the crux of the matter is the discovery by appellants of the cause of a problem, and the
determinative question is whether that cause would have been recognized by one of
ordinary skill in the art at the time the invention was made.”

The final words of Rader's dissent:

Chapman, therefore, unexpectedly discovered the true source of the additional 14-
hydroxy and solved the problem by removing the impurity from oxycodone salt.
Because the prior art could not have intended or appreciated Chapman’s discovery or
solution, this invention deserves patent protection.

See also

Submitted to Patently-O:

Of MaxDrei looking for commentary on PSA, note that Judge Rader's PSA approach to obviousness was rejected in the Chapman case. Perhaps a law prof can write on that.

See also


MaxDrei posted on PatentHawk:

The IPBiz blog has picked up and is running with this case, and its owner is interested in the way the EPO handles obviousness. But as an anonymity, I can't post to IPBiz, so I'll post here instead.

The Rader dissent in this "Chapman" case detects what in Europe we call a "problem invention". But that doesn't provide any indication that Rader favours the European "Problem and Solution Approach" to obviousness. Probably, like nearly everybody else, he hasn't begun to ponder whether it is worth looking at, from the point of view of adopting it. Instead, Rader finds support in old domestic US jurisprudence for recognising the non-obviousness of a "problem invention".


See Revolution EyeWear v Aspex

See Pointing Out the Problem to be Solved or Objects of the Invention


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