Ex parte Schwartz

Board of Patent Appeals and Interferences

Apr 22, 1998

08079222 (B.P.A.I. Apr. 22, 1998)

Application for patent filed June 17, 1993. According to1
appellant, this application is a continuation of Application
07/854,118, filed March 19, 1992, now abandoned.
1
THIS OPINION WAS NOT WRITTEN FOR PUBLICATION
The opinion in support of the decision being entered today (1)
was not written for publication in a law journal and (2) is
not binding precedent of the Board.
Paper No. 22
UNITED STATES PATENT AND TRADEMARK OFFICE
__________
BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________
Ex parte ROBERT S. SCHWARTZ
__________
Appeal No. 95-4847
Application No. 08/079,2221
__________
ON BRIEF
__________
Before COHEN, ABRAMS and FRANKFORT, Administrative Patent
Judges.
ABRAMS, Administrative Patent Judge.
DECISION ON APPEAL
This is an appeal from the decision of the examiner
finally rejecting claims 1-11 and 29-32. At that point,
claims 12-28 and 33-47 had been withdrawn from consideration
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Application No. 08/079,222
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as being drawn to a non-elected invention, and no claims had
been allowed. Along with the Appeal Brief (Paper No. 16), the
appellant filed an amendment canceling claims 9-11 and 30-32,
leaving claims 1-8 and 29 on appeal.
The appellant's invention is directed to an intraluminal
stent (claims 1-8) and to a method of preventing restenosis in
a body lumen (claim 29). The subject matter on appeal is
illustrated by reference to claims 1 and 29, which can be
found in an appendix to the Brief.
THE REFERENCES
The references relied upon by the examiner to support the
final rejection are:
Spears 5,092,841 Mar. 3,
1992
European application 0,364,787 Apr. 25,
1990
(Schatz)
THE REJECTION
Claims 1-8 and 29 stand rejected under 35 U.S.C. § 103 as
being unpatentable over Schatz in view of Spears.
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Application No. 08/079,222
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The rejection is explained in the Examiner's Answer.
The opposing viewpoints of the appellant are set forth in
the Brief and the Reply Brief.
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Application No. 08/079,222
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OPINION
In rejecting claims under 35 U.S.C. § 103, the examiner
bears the initial burden of presenting a prima facie case of
obviousness (see In re Rijckaert, 9 F.3d 1531, 1532, 28 USPQ2d
1955, 1956 (Fed. Cir. 1993) which is established when the
teachings of the prior art itself would appear to have
suggested the claimed subject matter to one of ordinary skill
in the art (see In re Bell, 991 F.2d 781, 783, 26 USPQ2d 1529,
1531 (Fed. Cir. 1993)). This is not to say, however, that the
claimed invention must expressly be suggested in any one or
all of the references, rather, the test for obviousness is
what the combined teachings of the references would have
suggested to one of ordinary skill in the art (see Cable
Electric Products, Inc. v. Genmark, Inc., 770 F.2d 1015, 226
USPQ 881 (Fed. Cir. 1985)).
Schatz discloses a deformable metal stent which may, with
reference to Figures 5 and 6, have a “biological compatible
coating 90 upon wall surfaces 74" (page 7, column 2, lines 27-
29). Examples of the coatings are absorbable polymers which
could contain drugs whereby, as the coating dissolves, the
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Application No. 08/079,222
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drug is slowly released into the body passageway (page 7,
column 2, lines 50-57). Thus, Schatz would have taught one of
ordinary skill in the art to place a film on the outer surface
of a stent which would interact with the body lumen in which
the stent is installed. What Schatz does not explicitly teach
is that this film could be of fibrin, as is required by claims
1 and 29.
For this the examiner looks to Spears, which is directed
to a method for treating an arterial wall injured during
angioplasty. The primary method disclosed is positioning an
angioplasty catheter in the damaged area, and then delivering
a bioprotective material between the arterial wall and the
catheter so that it is entrapped therebetween and permeates
into the fissures and small vessels of the arterial wall (see
the Abstract and Figures 2 and 2A). One of the forms in which
the bioprotective material is provided is as a shell of
microspheres within which drugs can be encapsulated (column 7,
lines 39 and 40). Among the materials listed as the
encapsulating medium is fibrin (column 7, line 61). Spears
goes on to state:
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Disclosure of the invention thus far has
contemplated the injection of bioprotective material
26 between the inflating balloon and the arterial
wall. Another method . . . contemplates applying a
thin sleeve of such material to the external surface
of the LBA balloon. The thin sleeve is then
transferred to the luminal surface as a result of
heat and pressure (column 9, lines 19-26).
From the above, it is our view that Spears would have
suggested to one of ordinary skill in the art that fibrin in
the form of a pre-formed film of drug-containing microspheres
be placed on the external surface of the balloon element of an
angioplasty catheter and placed in contact with the interior
wall of a body lumen for the purpose of treating the wall.
It is our further view that one of ordinary skill in the
art would have found it obvious to coat the stents of Schatz
with fibrin in place of the coatings disclosed in Schatz,
suggestion being found in the explicit teachings of Schatz and
Spears referred to above, which establish the desirability of
(1) coating a stent with materials to be applied to the walls
of the body lumen and (2) utilizing fibrin as such a material.
We note here that the prior art teachings relied upon need not
disclose the same advantage that the appellant alleges, for
all that is required is that there is a reasonable suggestion
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to combine the references. See In re Kronig, 539 F.2d 1300,
1304, 190 USPQ 425, 427-428 (CCPA 1976); and Ex parte Obiaya,
227 USPQ 58, 60 (Bd. Pat. App. & Int. 1985), aff’d. mem., 759
F.2d 1017 (Fed. Cir. 1986).
Claims 1 and 29 further state that the fibrin is provided
by contacting fibrinogen with a fibrinogen-coagulating
protein. This is not explicitly set out in either reference.
However, it constitutes a product-by-process limitation which,
if the product is the same as a product of the prior art, adds
no patentable distinction to the claim. This principle is
discussed in In re Thorpe, 777 F.2d 695, 227 USPQ 964 (Fed.
Cir. 1985). The appellant has argued that the fibrin
disclosed in Spears is different from that which is recited in
claims 1 and 29, in that it is denatured, but has not pointed
out language in Spears which supports such a conclusion or
offered evidence to that effect. Fibrin is defined as an
insoluble blood protein resulting from the hydrolysis of
fibrinogen by the action of thrombin, which polymerizes to
form blood clots (see, for example, Hawley’s Condensed
Chemical Dictionary, Eleventh Edition, 1987), which would
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Application No. 08/079,222
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seem to cover the fibrin disclosed in Spears as well as that
recited in the appellant’s claims and disclosed in the
appellant’s specification.
We additionally note that claim 29 is directed to a
method comprising the single step of applying a stent
comprising a pre-formed fibrin film, which is followed by the
product-by-process limitation. In addition to the problem we
find with this which was explained above with regard to claim
1, claim 29 is limited to a single “step,” and to consider the
process limitation would add a second step and thus raise a
question of indefiniteness regarding this claim language.
For the reasons set forth above, it is our conclusion
that the combined teachings of Schatz and Spears establish a
prima facie case of obviousness with respect to the subject
matter recited in claims 1 and 29. This being the case, we
shall sustain the rejection of these two claims and, owing to
the appellant’s decision that claims 3, 4, 5, 7 and 8 will
stand or fall with claim 1 (Brief, page 8), the rejection of
those claims also.
Claim 2 adds to claim 1 the requirement that “the fibrin
is a fibrin in which residual coagulating protein has been
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Application No. 08/079,222
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neutralized.” In our view this also is a limitation that goes
to the process of manufacture of the fibrin. Therefore, for
the same reasons as were set forth above with regard to the
term “fibrin” as it is utilized in claim 1, we find claim 2
not to define over the combined teachings of the two
references, and we will sustain the rejection of claim 2.
Dependent claim 6 further limits claim 1 by adding the
limitation that “the fibrin is intermixed with a polymeric
material.” While polymeric material was disclosed in both of
the applied references, their collective teachings did not
include intermixing it with fibrin. We therefore will not
sustain the rejection of this claim.
We have carefully considered all of the appellant’s
arguments. However, as to those rejections which we have
sustained, the arguments have not persuaded us that the
positions taken by the examiner were in error. We observe
that there is a broad commonality of purpose in the
appellant’s invention and in those of the two references. The
object of the appellant’s invention is to repair vascular
injury by coating a stent with fibrin to place the fibrin at
the site to interact with the body (specification, page 3),
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the purpose of the Schatz invention is to place absorbable
polymers or drugs into contact with the lumen wall at the site
of the stent, and the function of the Spears invention is to
repair an injured arterial wall (column 1), which it
accomplishes by placing materials which include fibrin at the
site to interact with the body (columns 5-7). Thus, it is our
opinion that the references do not teach away from combining
their teachings, and that their teachings are applicable to
the appellant’s invention.
SUMMARY
The rejection of claims 1-5, 7, 8 and 29 is sustained.
The rejection of claim 6 is not sustained.
The decision of the examiner is affirmed-in-part.
No time period for taking any subsequent action in
connection with this appeal may be extended under 37 CFR
§ 1.136(a).
AFFIRMED-IN-PART
IRWIN CHARLES COHEN )
Appeal No. 95-4847
Application No. 08/079,222
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Administrative Patent Judge)
)
)
)
NEAL E. ABRAMS ) BOARD OF
PATENT
Administrative Patent Judge) APPEALS AND
) INTERFERENCES
)
)
CHARLES E. FRANKFORT )
Administrative Patent Judge)
Appeal No. 95-4847
Application No. 08/079,222
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Daniel W. Latham
Medtronic Inc.
7000 Central Avenue, N.E.
Minneapolis, MN 55432