JIMRO CO., LTD.

Patent Trials and Appeals Board

Jul 29, 2021

2021001017 (P.T.A.B. Jul. 29, 2021)

UNITED STATES PATENT AND TRADEMARK OFFICE
UNITED STATES DEPARTMENT OF COMMERCE
United States Patent and Trademark Office
Address: COMMISSIONER FOR PATENTS
P.O. Box 1450
Alexandria, Virginia 22313-1450
www.uspto.gov
APPLICATION NO. FILING DATE FIRST NAMED INVENTOR ATTORNEY DOCKET NO. CONFIRMATION NO.
15/522,406 04/27/2017 Matsuya MANABE Q232899 5196
23373 7590 07/29/2021
SUGHRUE MION, PLLC
2000 PENNSYLVANIA AVENUE, N.W.
SUITE 9000
WASHINGTON, DC 20006
EXAMINER
LOPEZ, LESLIE ANN
ART UNIT PAPER NUMBER
3774
NOTIFICATION DATE DELIVERY MODE
07/29/2021 ELECTRONIC
Please find below and/or attached an Office communication concerning this application or proceeding.
The time period for reply, if any, is set in the attached communication.
Notice of the Office communication was sent electronically on above-indicated "Notification Date" to the
following e-mail address(es):
PPROCESSING@SUGHRUE.COM
USPTO@sughrue.com
sughrue@sughrue.com
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte MATSUYA MANABE
Appeal 2021-001017
Application 15/522,406
Technology Center 3700
Before JOHN C. KERINS, JILL D. HILL, and
CYNTHIA L. MURPHY, Administrative Patent Judges.
HILL, Administrative Patent Judge.
DECISION ON APPEAL
STATEMENT OF THE CASE
Pursuant to 35 U.S.C. § 134(a), Appellant1 appeals from the
Examiner’s decision to reject claims 13, 15, and 17–202, which constitute all
the claims pending in this application. We have jurisdiction under
35 U.S.C. § 6(b). A video oral hearing was conducted on July 15, 2021.

1 We use the word Appellant to refer to “applicant” as defined in 37 C.F.R.
§ 1.42(a). Appellant identifies the real party in interest as JIMRO CO.,
LTD. Appeal Br. 3.
2 Claims 1–12 are canceled. Claims 13–24 are pending. Claims 14, 16, and
21–24 are withdrawn. Final Act. 2.

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Application 15/522,406

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We REVERSE.
BACKGROUND
Sole independent claim 13, reproduced below, represents the claimed
subject matter:
13. A drug-eluting stent having a net-like main body which is
made of a metal or a polymeric material and has flection
sections, wherein a surface of the main body is coated with a
mixture comprising cilostazol and a bioabsorbable polymer,
wherein the bioabsorbable polymer comprises
(a) a polymer comprising DL lactide and glycolide in a
weight ratio of 7:3 - 9:1, whose molecular weight is 40,000 -
400,000,
(b) a polymer comprising DL lactide whose molecular
weight is 50,000 - 100,000,
(c) a polymer comprising L lactide and DL lactide in a
weight ratio of 6:4 - 8:2, whose molecular weight is 300,000 -
600,000,
(d) a polymer comprising L lactide whose molecular
weight is 50,000 - 150,000, or
(e) a polymer comprising L lactide and caprolactone in a
weight ratio of 6:4 - 8:2, whose molecular weight is 150,000 -
400,000.

REJECTIONS
I. Claims 13, 15, and 18 stand rejected under 35 U.S.C. § 103 as
unpatentable over Rypacek, Pohjonen, and Iguchi. Final Act. 8.
II. Claim 17 stands rejected under 35 U.S.C. § 103 as unpatentable
over Rypacek, Iguchi, and Tartaglia. Final Act. 10.
III. Claims 19 and 20 stand rejected under 35 U.S.C. § 103 as
unpatentable over Rypacek, Pohjonen, Iguchi, and Sirhan. Final Act. 11.
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Application 15/522,406

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ANALYSIS
Rejection I
Claim 13 recites a drug-eluting stent coated with a mixture comprising
the antiplatelet drug cilostazol and a bioabsorbable polymer, the
bioabsorbable polymer having a specific combination of weight ratios and
ranges of molecular weights of DL lactide polymer, L lactide polymer, and a
polymer combination of DL lactide and L lactide polymers. See Appeal Br.
27 (Claims App.).
The Examiner finds that Rypacek discloses, inter alia, a drug-eluting
stent “coated with a mixture comprising [an antiplatelet] drug and a
bioabsorbable polymer . . . whose molecular weight is 300,000 - 600,000.”
Final Act. 8 (citing Rypacek ¶¶ 83, 271–273, 334). The Examiner also finds
that Rypacek’s bioabsorbable polymer comprises L lactide and DL lactide in
a weight ratio of 1:1. Id. (citing Rypacek ¶ 335). The Examiner admits that
Rypacek does not disclose the bioabsorbable polymer comprising L lactide
and DL lactide in the claimed weight ratio of 6:4 - 8:2, but finds that
Pohjonen discloses this L lactide and DL lactide weight ratio of 6:4 - 8:2 for
use with implants. Id. at 8–9 (citing Pohjonen 3:19–53, 1:6–18). The
Examiner reasons that, because Pohjonen and Rypacek are concerned with
the same field of endeavor, namely implants coated with polymers
comprising L lactide and DL lactide, it would have been obvious to “modify
Rypacek such that the polymer comprises L lactide and DL lactide in a
weight ratio of 6:4 - 8:2 as taught by Pohjonen as it is a simple substitution
of one known element for another to obtain predictable results. Id. at 9
(citing MPEP § 2143).
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The Examiner then admits that the combination of Rypacek and
Pohjonen does not disclose the drug being cilostazol, but finds that Rypacek
discloses the concentration of its antiplatelet drug encompassing 50% by
weight, and lguchi discloses a stent with a drug-polymer coating “where the
drug is cilostazol at 50% by weight.” Final Act. 9 (citing Iguchi 13:15–35,
Rypacek ¶ 26). The Examiner reasons that lguchi, Rypacek, and Pohjonen
“are concerned with the same field of endeavor, namely polymer coatings
for stents,” so that it would have been obvious to “modify the combination
of Rypacek and Pohjonen such that the drug is cilostazol as taught by lguchi
. . . to inhibit thrombogenesis at the stent surface and to inhibit endothelial
cell proliferation of the blood vessel. Id. (citing Iguchi 7: 18–30).
Appellant initially notes:
In cases involving the chemical arts––such as the
presently claimed invention––the Federal Circuit has held that
it is particularly necessary to articulate some reason that would
have led a person of ordinary skill in the art to modify a known
composition in a particular manner to obtain a predictable
outcome. See, e.g., Eisai Co. Ltd v. Dr. Reddy's Laboratories,
Ltd, 533 F.3d 1353, 1359 (Fed. Cir. 2008). This is because the
chemical arts are unpredictable and thus potential solutions are
less likely to be genuinely predictable. See id.
Appeal Br. 8.
Appellant argues, inter alia, that “the cited prior art does not address
the unpredictability and difficulties in developing a matrix for delivering a
poorly-soluble drug like cilostazol from a DES.” Appeal Br. 12. Appellant
also argues that a skilled artisan “would not have had a reasonable
expectation of success.” Id.
Appellant contends that “small changes in the repeating units and/or
[molecular weight] of the polymer can produce very different results,” as
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evidenced by Figure 5 of their Specification, which shows “wide variation in
dissolution at the same [molecular weight].” Appeal Br. 16. Appellant
argues that “Pohjonen does not overcome this unpredictability in the art” and
a skilled artisan “would not have had any reason to think that Pohjonen's
polymer is suitable for delivering a poorly-soluble drug like cilostazol.” Id.
The Examiner responds that solubility is not recited in the claims.
Ans. 4. The Examiner also disagrees that Appellant’s Figure 5 establishes
poor solubility of cilostazol. Id. at 7. The Examiner does not, however,
discuss the predictability of the art and its effect on whether it would have
been obvious to change the weight ratio of L lactide and DL lactide, or
substitute cilostazol for Rypacek’s antiplatelet drug.
Appellant has the better argument, given the Federal Circuit’s
guidance that the chemical arts are unpredictable, making potential solutions
less likely to be genuinely predictable. This unpredictability makes it
particularly necessary to articulate a reason why a skilled artisan would
modify a known composition in a particular manner to obtain a predictable
outcome. See Eisai, 533 F.3d at 1359. Here, Appellant’s Specification
discusses the poor solubility of cilostazol, and the resulting difficulty in
creating a nanoparticle therewith for coating a stent. Spec. ¶¶ 7–8, 12, 14,
and 32. The Examiner’s reasoning is conclusory in stating that it would
have been obvious to “modify Rypacek such that the polymer comprises L
lactide and DL lactide in a weight ratio of 6:4 - 8:2 as taught by Pohjonen as
it is a simple substitution of one known element for another to obtain
predictable results.” Final Act. 9. Merely alleging predictable results in an
unpredictable art falls short of providing a rational basis. Further, the
Examiner concludes that replacing Rypacek’s antiplatelet drug with Iguchi’s
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antiplatelet drug would have been obvious “to inhibit thrombogenesis at the
stent surface and to inhibit endothelial cell proliferation of the blood vessel.”
Id. Since Rypacek already includes an antiplatelet drug, the Examiner’s
reasoning, again, seems to be substitution of one known element –– an
antiplatelet drug –– for another to obtain predictable results, which is
insufficient in an unpredictable art.
None of Sirhan, Dave, or Turnell, noted by the Examiner as teaching
cilostazol with a lactic acid polymer (Final Act. 3), remedies the Examiner’s
lack of a reasoning with rational basis. First, the teachings of these
references are not incorporated into the pending rejections. The Examiner
contends that, because these references “teach the same type of polymer as
the combination of Rypacek and Pohjonen, it is clear that one of ordinary
skill in the art . . . would understand cilostazol to be easily used with the
polymer of Rypacek.” Final Act. 3. Lacking an explanation of why the
specific combinations of Sirhan, Dave, and Turnell establish that combining
cilostazol with L lactide and DL lactide in a certain weight ratio is
predictable, the Examiner has not establish the predictability alleged in the
stated reason for combining Rypacek, Pohjonen, and Iguchi.
For these reasons, we do not sustain the rejection of independent
claim 13 as obvious over Rypacek, Pohjonen, and Iguchi. Claims 15 and 18
depend from claim 13. We do not sustain Rejection I. Claims 17, 19, and
20 also depend from claim 13, and none of the remaining references or
Examiner analyses cure this deficiency, and thus we do not sustain
Rejections II or III for the same reasons.
CONCLUSION
The Examiner’s rejections are not sustained
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DECISION SUMMARY
In summary:
Claims
Rejected
35 U.S.C. § Reference(s)/Basis Affirmed Reversed
13, 15, 18 103 Rypacek, Pohjonen,
Iguchi
13, 15, 18
17 103 Rypacek, Iguchi,
Tartaglia
17
19, 20 103 Rypacek, Pohjonen,
Iguchi, Sirhan
19, 20

REVERSED