Ex Parte Dolan et al

Board of Patent Appeals and Interferences

Mar 9, 2012

11689733 (B.P.A.I. Mar. 9, 2012)

UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________

Ex parte MARK DOLAN, MATTHEW J. BIRDSALL,
EUGENE TEDESCHI, JOSEPH BERGLUND, and
RAFFY BROWN
__________

Appeal 2010-009548
Application 11/689,733
Technology Center 3700
__________

Before DEMETRA J. MILLS, ERIC GRIMES, and FRANCISCO C.
PRATS, Administrative Patent Judges.

GRIMES, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 involving claims related to
methods of treating vascular conditions. The Examiner has rejected the
claims as anticipated or obvious. We have jurisdiction under 35 U.S.C.
§ 6(b). We reverse.
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Application 11/689,733

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STATEMENT OF THE CASE
The Specification discloses that “[d]rug-coating stents can improve
the effectiveness of stents” (Spec. 1, ¶ 0002) but “some drug polymers
remain on the stent after their function of drug delivery has been completed
… [and] may cause an unfavorable result, such as thrombogenesis” (id. at 1,
¶ 0003). The Specification discloses “a method for treating a vascular
condition … [that] includes delivering a stent to a target region of a vessel,
the stent including a drug polymer coating” (id. at 1, ¶ 0005). “The method
continues by eluting the elution portion from the delivered stent for an
elution period, heating the delivered stent after the elution period and
removing the remaining portion based on the heating” (id.).
Claims 1-20 are on appeal. Claim 1 is representative and reads as
follows:
1. A method for treating a vascular condition, the method comprising:
delivering a stent to a target region of a vessel to produce a delivered
stent, the stent including a drug polymer coating including a therapeutic
agent releasable through action of bodily processes in the vessel;
maintaining the delivered stent in the vessel for an elution period to
elute the therapeutic agent from the delivered stent and produce a reduced
stent having a remaining portion of the drug polymer coating; and
heating the reduced stent after the elution period to remove the
remaining portion from the reduced stent.

The Examiner has rejected claims 1-4, 8, 10, 11, 14, 16, 17, and 20
under 35 U.S.C. § 102(b) as anticipated by Daum.1 The Examiner has also
rejected, under 35 U.S.C. § 103(a), claims 5 and 19 in view of Daum, claims

1 Daum et al., Patent Application Publication US 2002/0128704, Sept. 12,
2002.
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6, 7, 12, and 13 in view of Daum and Kandarpa,2 and claims 9, 15, and 18 in
view of Daum and Sahatjian.3 The same issue is dispositive for all of the
rejections.
The Examiner finds that Daum discloses delivering a drug polymer
coated stent to a vessel target region, “maintaining the delivered stent in the
vessel for an elution period to elute the therapeutic agent … and produce a
reduced stent … and heating the reduced stent after the elution period to
remove the remaining portion from the reduced stent” (Answer 3). The
Examiner finds that Daum discloses that the “the drug can be eluted without
the use of heat and just using breakdown and diffusion alone caused by
exposure to blood flow” (id., citing Daum at ¶ 0016).
Appellants argue that Daum does not disclose “maintaining the
delivered stent in the vessel for an elution period to elute the therapeutic
agent … and produce a reduced stent” and subsequently heating the reduced
stent, as required by the claims, because Daum discloses that heating is
required to release the therapeutic agent from the encapsulation matrix
(Appeal Br. 11). Appellants also argue that the Specification makes clear
that the “eluting period” of claim 1 does not involve heating (id. at 12).
The Examiner responds that blood flow would promote release of the
therapeutic agent from Daum’s stent in the absence of heat and that the
heating step of Daum is intended “to enhance or increase an already ongoing
physical release” in certain embodiments (Answer 7, citing Daum at ¶ 0020).
The Examiner also reasons that none of the claims “preclude the elution

2 Kandarpa et al., US 5,323,778, June 28, 1994
3 Sahatjian et al., US 6,409,716 B1, June 25, 2002
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Application 11/689,733

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period from having a heating step” (id. at 6), and that Daum discloses a first
heated elution period and a subsequent heated step (id. at 8, citing Daum at
¶¶ 0011 and 0016).
We agree with Appellants that the Examiner has not adequately
shown that Daum anticipates claim 1. When the claim language is read in
light of the Specification, the step of “maintaining the delivered stent in the
vessel for an elution period to elute the therapeutic agent” would be
interpreted to be conducted in the absence of heat. That is, the Specification
discloses that drug polymer coatings “must … be able to control release the
drug at sufficient therapeutic levels of several days, weeks or longer” (Spec.
1, ¶ 0003) and that the problem to be solved by the claimed method is
getting rid of drug-containing polymer after the elution period is completed
(id. at ¶¶ 0003-0004).
It is in this context that the Specification describes the disclosed
method as including separate steps of “eluting the elution portion from the
delivered stent for an elution period, [and] heating the delivered stent after
the elution period and removing the remaining portion based on the heating”
(Spec. 1, ¶ 0005 (emphasis added)). The Specification also discloses that
“[a]fter elution of the therapeutic agent, the method continues to include
heating the stent” (id. at ¶ 0007). Thus, when claim 1 is read in view of the
Specification, the broadest reasonable interpretation of “heating the reduced
stent after the elution period” (emphasis added) requires separate elution and
heating steps; i.e., the elution step does not include heating the stent.
Daum does not disclose an elution step that is conducted without
heating. Daum discloses “a stent prepared to deliver drugs when heated by
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electromagnetic fields” (Daum 1, ¶ 0002). Daum discloses that “the drug
can be released by elevated temperatures from within or at the surface of the
stent, it can be activated (or deactivated) by elevated temperatures … and/or
the drug-adjacent tissue reaction can be enhanced by elevated temperatures”
(id. at 1, ¶ 0008). Daum discloses that “[i]n all cases the stent-carried drug
will not be available or be active at body temperature, but it becomes
available or active at a certain temperature point above body temperature”
(id. at 2, ¶ 0011) and that “[i]n order to make the drug available or active at
the stent surface, the stent with the drug has to be heated” (id.).
Thus, Daum does not disclose method of claim 1 because Daum does
not disclose an elution period in which a therapeutic agent is eluted in the
absence of heat. Claims 11 and 17 also require a first elution step and a
subsequent heated removal step. Thus, we reverse the anticipation rejection
of claims 1-4, 8, 10, 11, 14, 16, 17, and 20.
With regard to the rejections under 35 U.S.C. § 103(a), the Examiner
relies on the same findings and reasoning with regard to Daum, as discussed
above, and thus we also reverse these rejections.
SUMMARY
We reverse the rejection of claims 1-4, 8, 10, 11, 14, 16, 17, and 20
under 35 U.S.C. § 102(b). We also reverse the rejection of claims 5-7, 9, 12,
13, 15, 18, and 19 under 35 U.S.C. § 103(a).

REVERSED

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