Ex Parte Houston et al

Board of Patent Appeals and Interferences

Feb 27, 2008

10300298 (B.P.A.I. Feb. 27, 2008)

UNITED STATES PATENT AND TRADEMARK OFFICE
____________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
____________

Ex parte JOHN GRAEME HOUSTON,
PETER ARNO STONERBRIDGE, JOHN BRUCE CAMERON DICK,
ROBERT GORDON HOOD, ALLANA JOHNSTONE,
CHRISTOPHE EMMANUEL SARRAN, and CRAIG MCLEOD DUFF
____________

Appeal 2008-0106
Application 10/300,298
Technology Center 3700
____________

Decided: February 27, 2008
____________

Before DONALD E. ADAMS, LORA M. GREEN, and
RICHARD M. LEBOVITZ, Administrative Patent Judges.

GREEN, Administrative Patent Judge.

DECISION ON APPEAL
This is a decision on appeal under 35 U.S.C. § 134 from the
Examiner’s final rejection of claims 21 and 23-31. We have jurisdiction
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Application 10/300,298

under 35 U.S.C. § 6(b). Claims 21, 25, and 26 are representative of the
claims on appeal, and read as follows:
21. A tube for a human or animal body, the tube comprising a flexible
tubular material, a side wall of the tube being deformed to form a helical
formation in an internal surface of the side wall of the tube, and a
corresponding helical indentation in an external surface of the side wall,
there being a coating applied to the indentation, the coating ensuring that the
helical formation maintains its shape.

25. A tube according to claim 21, wherein the coating comprises a
polymeric material.

26. A tube according to claim 25, wherein the polymeric material
comprises polyurethane.

The Examiner relies on the following references:
Houston WO 00/38591 A2 6 July 2000
Burkoth WO 98/23228 A1 4 June 1998
We affirm.

DISCUSSION
Claims 21 and 23-31 stand rejected under 35 U.S.C. § 103(a) as being
obvious over the combination of Houston and Burkoth. As Appellants do
not argue the claims separately, claims 23-31 stand or fall with claim 21, and
we thus focus our analysis on claim 21. 37 CFR § 41.37(c)(1)(vii).
According to the Examiner, Houston discloses “the invention as
claimed except for particularly disclosing coating the external helical
indentation with a [polymeric material containing a] therapeutic substance.”
(Ans. 3.)
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The Examiner cites Burkoth as evidence that such coating methods
are well known in the art (id.). Burkoth is cited for teaching a tube-type
stent comprising a helical groove on the external surface of the stent. In
particular, the Examiner notes:
With regards to newly added functional language “the coating
ensuring that the helical formation maintains its shape”, it
should be noted that [the] polymeric coating . . ., when cured,
creates a solid layer that will inherently ensure/help [the]
groove . . . maintain its shape (i.e., prevents collapsing of the
groove during expansion of the stent and/or when the stent is
pressed against the blood vessel). It is noted that the Applicants
claim polyurethane (see dependent claim 26) as the polymeric
material comprising the coating. Since Burkoth et al.’s coating
may comprise polyurethane, and since polyurethane is the same
coating material as Applicants’, therefore it will inherently
provide some level/degree of structural stability. Therefore, it
would have been obvious to a person having ordinary skill in
the art at the time the invention was made to have combined the
teaching of coating an external helical indentation with a
therapeutic substance, with the tube of Houston et al., as taught
by Burkoth et al., in order to prevent restenosis, thrombosis,
inflammation, to encourage healing, and/or to provide
numerous other treatments/advantages such as ensuring/helping
the helical groove to maintain its shape.

(Ans. 3-4.)
“In rejecting claims under 35 U.S.C. § 103, the examiner bears the
initial burden of presenting a prima facie case of obviousness. Only if that
burden is met, does the burden of coming forward with evidence or
argument shift to the applicant.” In re Rijckaert, 9 F.3d 1531, 1532 (Fed.
Cir. 1993) (citations omitted). The question of obviousness is resolved on
the basis of underlying factual determinations including: (1) the scope and
content of the prior art; (2) the level of ordinary skill in the art; (3) the
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differences between the claimed invention and the prior art; and (4)
secondary considerations of nonobviousness, if any. Graham v. John Deere
Co., 383 U.S. 1, 17 (1966). The Supreme Court has recently emphasized
that “the [obviousness] analysis need not seek out precise teachings directed
to the specific subject matter of the challenged claim, for a court can take
account of the inferences and creative steps that a person of ordinary skill in
the art would employ.” KSR Int’l v. Teleflex Inc., 127 S. Ct. 1727, 1741
(2007). “The combination of familiar elements according to known methods
is likely to be obvious when it does no more than yield predictable results.”
Id. at 1739. Moreover, an “[e]xpress suggestion to substitute one equivalent
for another need not be present to render such substitution obvious.” In re
Fout, 675 F.2d 297, 301 (CCPA 1982).
Appellants argue that there is no motivation to combine Burkoth and
Houston (App. Br. 5). Appellants assert that Houston does not suggest that
the stents disclosed may require additional support to maintain the helical
formation, and Burkoth does not suggest that the active agent serves any
structural role (id.). Thus, Appellants argue that it “appears that the
Examiner is employing impermissible hindsight to combine these references,
as the only suggestion for their combination comes from the present
disclosure.” (Id.)
Appellants’ arguments are not convincing. Houston teaches a tube
“comprising a flexible tubular material, a side wall of the tube being
deformed to form a helical formation in an internal surface of the side wall
of the tube, and a corresponding helical indentation in an external surface of
the side wall,” as required by claim 21 (see Ans. 3). As noted by the
Examiner (Ans. 5), Houston teaches a numerous therapeutic uses for the
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tubing, such as for an implant in various locations in the cardiovascular
system, and as a stent (Houston, p. 5). Burkoth teaches that it is known to
the ordinary artisan that external indentations in therapeutic implants, such
as stents, may be filled with a therapeutic substance that can be delivered
through the use of a biocompatible polymer, such as a polyurethane
(Burkoth, pp. 2-5, 13). Thus, it would have been obvious to the ordinary
artisan to fill the external indentations of the tube of Houston with a
therapeutic agent delivered through the use of the biocompatible polymer
polyurethane, in order to achieve site-selective delivery of the therapeutic.
As polyurethane is one of the claimed coatings (claim 26) that may be used
to ensure that the helical formation maintains it shape, the tube taught by the
combination is the same as the tube of claim 21.
As noted by the United States Supreme Court,

If a person of ordinary skill can implement a predictable
variation, § 103 likely bars its patentability. For the same
reason, if a technique has been used to improve one device, and
a person of ordinary skill would recognize that it would
improve similar devices in the same way, using the technique is
obvious unless its actual application is beyond his or her skill.

KSR, 127 S. Ct. at 1740.
Appellants assert that the combination is improper as “the Burkoth
patent does not teach or disclose a coating having any structural support
capabilities.” (App. Br. 4.) According to Appellants, the active agent
disclosed in the Burkoth patent is an anti-inflammatory agent, and thus
would likely dissolve and disappear as the drugs are delivered to the site,
leaving only the groove, and thus a weakened area of the stent (id. at 5).
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Burkoth teaches that the therapeutic compound, such as the anti-
inflammatory, can be delivered through a biocompatible delivery matrix,
such as a biocompatible polymeric matrix (Burkoth, p. 13, ll. 3-6). Burkoth
specifically teaches that the biocompatible polymeric matrix may be a
polyurethane (id. at ll. 6-10). Thus, as Burkoth teaches adding the same
material to the external grooves, i.e., polyurethane, it would inherently have
the property of providing support to the helical formation. Thus, the
preponderance of the evidence of record supports the Examiner’s position,
and the rejection is affirmed. See, e.g., Ethicon, Inc. v. Quigg, 849 F.2d
1422, 1427 (Fed. Cir. 1988) (explaining the general evidentiary standard for
proceedings before the Office.
No time period for taking any subsequent action in connection with
this appeal may be extender under 37 C.F.R. § 1.136(a)
AFFIRMED

Renner, Kenner, Greive, Bobak, Taylor & Weber
Fourth Floor
First National Tower
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