Ex Parte Weber et al

Board of Patent Appeals and Interferences

Aug 10, 2012

11085780 (B.P.A.I. Aug. 10, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________

Ex parte JAN WEBER, KARL JAGGER, and LILIANA ATANASOSKA
__________

Appeal 2011-002711
Application 11/085,780
Technology Center 3700
__________

Before LORA M. GREEN, FRANCISCO C. PRATS, and
JACQUELINE WRIGHT BONILLA, Administrative Patent Judges.

BONILLA, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 involving claims directed to a
catheter assembly comprising a balloon, an intraluminal medical device, and
a degradable coating. The Examiner has rejected the claims as obvious. We
have jurisdiction under 35 U.S.C. § 6(b). We affirm.

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STATEMENT OF THE CASE
The Specification describes a degradable coating for use on
components of a catheter assembly (Spec. 2, ll. 18-21). The “coating may be
fabricated in multi-layer films assembled through the sequential absorption
of oppositely charged species during a stepwise absorption from solution”
(id. at 9, ll. 23-25). For example, the coating may be “a layer-by-layer (LbL)
coating having at least one first layer and one second layer, the first layer
including a positively charged material, and the second layer adjacent the
first layer including a negatively charged material” (id. at 3, ll. 1-6). The
Specification describes coatings that degrade over seconds, minutes or days
(id. at 7, ll. 6-7). Examples of suitable materials for the coating include
hydrophilic polymers, such as polyethylene oxide and polysaccharides (id. at
7, l. 23 – 8, l. 2). In one embodiment, a coating may be disposed over both a
stent and an expandable balloon member (id. at 8, l. 34 – 9, l. 2).
Claims 1 and 3-35 are on appeal, with claims 1, 19, 25, and 26 being
independent. Claim 1 is representative and reads as follows (emphasis
added):
1. A catheter assembly comprising:
an expandable balloon member having an inner surface and an
outer surface;
an expandable intraluminal medical device having an inner
surface and an outer surface disposed on the expandable balloon
member; and
a degradable coating in contact with at least a portion of the
inner surface, the outer surface, or both of the expandable intraluminal
medical device and in contact with at least a portion of the outer
surface of the expandable balloon member, the degradable coating
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securing the intraluminal medical device to the expandable balloon
member,
the degradable coating is a layer-by-layer coating comprising
at least one first layer that has a negative charge or a positive charge
and at least one second layer adjacent the first layer, the second layer
comprises a second charge opposite that of the first layer and is
electrostatically disposed thereon, the coating selected so as to release
the expandable intraluminal medical device from the expandable
balloon member upon expansion or contraction of the expandable
balloon member from an inflated state upon exposure to an
environment within the body.
Independent claims 19, 25, and 26 likewise recite a catheter assembly,
as well as a degradable coating comprising at least a first and second layer,
each layer (or polymer material in the layer) having a charge that is opposite
of that of the other layer (or polymer material in the other layer), where
layers are “electrostatically disposed thereon.”
The claims stand rejected as follows:
• Claims 1, 3-15, 19-26, and 28-35 under 35 U.S.C. § 103(a) as
obvious over Ryan (U.S. Pat. No. 6,391,033 B2, issued May 21, 2002) in
view of Lynn et al. (U.S. Pat. No. 7,112,361 B2, issued September 26,
2006).
• Claim 27 under 35 U.S.C. § 103(a) as obvious over Ryan in view of
Lynn, and further in view of Fischell (U.S. Pat. Appl. Pub. No.
2002/0052639 A1, published May 2, 2002).
• Claims 16-18 under 35 U.S.C. § 103(a) as obvious over Ryan in
view of Lynn, and further in view of Shanley (U.S. Pat. No. 6,764,507,
issued July 20, 2004).
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I.
Issues
Does the Examiner establish that independent claim 1 is obvious over
Ryan in view of Lynn? Specifically, does the Examiner establish that a
skilled artisan would have been motivated to use a layer-by-layer coating
comprising layers with opposite net charges as described in Lynn in a
coating of a stent delivery device described in Ryan?
Principles of Law
The Examiner bears the initial burden, on review of the prior art or on
any other ground, of presenting a prima facie case of unpatentability. In re
Oetiker, 977 F.2d 1443, 1445 (Fed. Cir. 1992). If the Examiner meets that
initial burden, the burden of coming forward with evidence or argument
shifts to the applicant. In re Rijckaert, 9 F.3d 1531, 1532 (Fed. Cir. 1993).
After the applicant submits such evidence or argument, the PTO then
determines patentability “on the totality of the record, by a preponderance of
evidence with due consideration to persuasiveness of argument.” Oetiker,
977 F.2d at 1445.
Analysis
The Examiner states that Ryan discloses all elements recited in the
pending independent claims, except that “[a]lthough Ryan contemplates a
coating of more than one layer, Ryan does not disclose a first layer having a
net negative or positive charge and a second layer having a net charge
opposite of the first” (Ans. 4). The Examiner finds that Lynn describes a
degradable layer-by-layer coating having at least two layers, where a first
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layer has a net charge that is opposite to that of a second layer, where the
layers are electrostatically disposed onto one another (id.).
Appellants argue that Ryan teaches “an upper limit of five minutes …
as the requisite dissolution time” of a relevant degradable coating (App. Br.
15), and that the coating will dissolve in “no more than 30 minutes, not
hours” (Reply Br. 4, 5, 7). By contrast, according to Appellants, “Lynn
discloses erosion rates for various polymers as being 9 hours (Poly 1/PAA
and Poly 1/SPS), 40 hours (Poly 1/SPS) and 50 hours (Poly 1/DNA)” (App.
Br. 15). Appellants assert that Lynn provides no guidance “as to what
materials might be selected that would result in such a drastic decrease in
decomposition from 9 hours to 40 hours to as little as 1-5 minutes as
disclosed by Ryan for percutaneous procedures” (id. at 16). Thus, according
to Appellants, one would not have seen the benefit of substituting the
degradable coatings of Lynn with those of Ryan, and therefore an ordinary
artisan would have had no motivation to combine the teachings of the
references (id. at 19; Reply Br. 2, 6).
Appellants (App. Br. 14) point to a paragraph in Ryan that states in
one sentence: “In practice, a range of dissolving time from about one
minute to thirty minutes will be most useful” (Ryan, col. 7, ll. 61-63.) This
sentence, however, does not limit the disclosed degradable coating to one
that dissolves within 30 minutes. As noted by the Examiner, this sentence in
Ryan refers to a range of time that “is merely preferred” (Ans. 7).
Moreover, in the same paragraph, Ryan also teaches that the “time to
dissolution in the body can be controlled by choice of material, by the
thickness applied to the stent assembly, and by mixing of different
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compounds” (Ryan, col. 7, ll. 50-52; Ans. 7). Consistently, Ryan states
elsewhere that “the variety and number of useful compounds is far too long
to list” and “any material or combination of material with sufficient material
strength, optimal disintegration time frame within the body, and acceptable
level of harmful side effects may be used” (id. at col. 7, ll. 21-26).
As noted by the Examiner (Ans. 7; Final Office Action 5), Lynn
likewise teaches that degradation times of the disclosed coating can be
varied as needed by changing the composition and thickness of the coating.
We disagree with Appellants that Lynn’s teachings, including Lynn’s use of
the phrase “fine-tuned” (App. Br. 17, 19; Reply Br. 8), teach or suggest only
a “composition of polyanionic and polycationic layers” (Lynn, col. 10, ll.
21-23) having a degradation rate of at least nine hours. Lynn describes
degradation rates of 9, 40 or 50 hours with regard to one example, relating to
compounds comprising one polymer “for use in initial experiments” (id. at
col. 13, ll. 58-61). This example does not limit the Lynn teachings to certain
particular coatings that take hours to degrade, especially when Lynn teaches
elsewhere that “[a]lternatively, the polyelectrolyte layers may be rendered
more hydrophilic to increase their hydrolytic degradation rate” (id. at col.
10, ll. 27-29) and “[i]n certain embodiments, the degradation rate of a given
layer can be adjusted by including a mixture of polyelectrolytes that degrade
at different rates or under different conditions” (id. at ll. 29- 32).
Thus, both Ryan and Lynn teach that one can vary degradation times
of a relevant coating, depending on what is optimal in a given situation.
Consistently, we note that Ryan refers to a “great many compositions” that
can be used, i.e., natural and synthetic substances (Ryan, col. 6, ll. 35-39)
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such as polysaccharides (id. at col. 7, ll. 7-14), “a very slowly dissolving
material such as a starch” (id. at ll. 52-58), polyethylene oxide, or polyvinyl
alcohol (id. at col. 6, ll. 55-57). Lynn likewise refers to a large list of
possible degradable polyelectrolytes, such as biodegradable polysaccharides
and polymers including polyethylene oxide and polyvinyl alcohol (Lynn,
col. 8, l. 36-37; col. 5, ll. 65 -67). Thus, given that both references describe
the use of similar substances to produce coatings that degrade in a patient’s
body, an ordinary artisan would have been motivated to look to Lynn for
possible choices of degradable coatings and techniques to be used, for
example, when making a multi-layered coating material used to secure a
stent to a balloon, as described in Ryan (col. 5, ll. 22-26; see also col. 6, ll.
64-67).
We are not persuaded by Appellants’ argument that neither cited
reference “contemplates the use of layer-by-layer techniques to dispose
subsequent polymers of opposite charges for the purpose of temporarily
securing a stent to a balloon or other catheter delivery component” (App. Br.
20; Reply Br. 3-4). As noted by the Examiner (Final Office Action 5), Ryan
teaches the use of a multi-layered degradable adhesive material (Ryan, col 5,
ll. 23-26; see also col. 6, ll. 64-67 ). In addition, this particular argument by
Appellants ignores what an ordinary artisan would have contemplated when
reading the cited references together, as discussed above.
We therefore agree with the Examiner that it “would have been
obvious to one having ordinary skill … to incorporate the technique of layer
by layer coating including layers with opposite net charges [as taught in
Lynn] into formation of the multilayer adhesive coating found in the stent
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delivery device of Ryan” (Ans. 4). We also agree with the Examiner that a
skilled artisan would have recognized that doing so “would positively result
in [] achieving the advantages taught by Lynn,” i.e., a simple, versatile, and
inexpensive technique (id. 4-5; see also Lynn col. 1, ll. 18-21).
Appellants do not argue claims 1, 3-15, 19- 26, 28-35 separately, and
therefore the claims fall together with any of the independent claims, such as
claim 1. 37 C.F.R. § 41.37(c)(1)(vii).
Conclusion of Law
We conclude that the Examiner establishes that claim 1, and therefore
claims 3-15, 19- 26, 28-35, are obvious over Ryan in view of Lynn.
II.
Issue
Does the Examiner establish that dependent claim 27 is obvious over
Ryan in view of Lynn, in further view of Fischell?
Analysis
On appeal, Appellants assert that “Claim 27 depends from claim 26,”
and “Claim 26 is not obvious over Ryan and Lynn for the reasons discussed
above” (App. Br. 21). Regarding Fischell, Appellants only argue that
“[c]ombining the sheath of Fischell with Ryan and Lynn fails to render
claim 26 obvious” (id. at 22). For the reasons above, Appellants’ arguments
do not persuade us.
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Conclusion of Law
We conclude that the Examiner establishes that dependent claim 27 is
obvious over Ryan in view of Lynn, in further view of Fischell.
III.
Issue
Does the Examiner establish that dependent claims 16-18 are obvious
over Ryan in view of Lynn, in further view of Shanley?
Analysis
On appeal, Appellants assert that “Claims 16-18 depend from claim
1,” and “Claim 1 has been discussed above and is not obvious over Ryan in
view of Lynn” (id. at 22). Regarding Shanley, Appellants only argue that
“combining the stent of Shanley still fails to render claim 1 obvious” (id.).
For the reasons above, Appellants’ arguments do not persuade us.
Conclusion of Law
We conclude that the Examiner establishes that dependent claims 16-
18 are obvious over Ryan in view of Lynn, in further view of Shanley.
SUMMARY
We affirm the obviousness rejections of claims 1, 3-15, 19-26, and 28-
35 over Ryan in view of Lynn, claim 27 over Ryan in view of Lynn and
Fischell, and claims 16-18 over Ryan in view of Lynn and Shanley.

Appeal 2011-002711
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TIME PERIOD FOR RESPONSE
No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a).

AFFIRMED

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