Ex Parte Wu et al

Patent Trial and Appeal Board

Mar 27, 2013

10663568 (P.T.A.B. Mar. 27, 2013)

UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE PATENT TRIAL AND APPEAL BOARD
__________

Ex parte STEVEN Z. WU, SYED F.A. HOSSAINY,
SAMEER HARISH, DEBORRA SANDERS-MILLARE,
and DARYUSH MIRZAEE
__________

Appeal 2011-013643
Application 10/663,568
Technology Center 1600
__________

Before TONI R. SCHEINER, LORA M. GREEN and
FRANCISCO C. PRATS, Administrative Patent Judges.

SCHEINER, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 from the rejection of claims
directed to an implantable medical device. The claims have been rejected as
obvious, indefinite, and lacking enablement. We have jurisdiction under 35
U.S.C. § 6(b).
We reverse.

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Application 10/663,568

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STATEMENT OF THE CASE
Claims 25, 28-32, and 34-37 are pending and on appeal. Claims 1-24,
26, 27, and 33 have been canceled (App. Br. 4).
Claims 25 and 32 are representative of the claimed subject matter:
25. A drug loaded stent, comprising:
a radially expandable stent body,
a coating layer disposed on the stent body, and
polymeric particles containing a therapeutic substance embedded with
the coating layer, wherein the coating layer comprises a polymer different
than the polymer from which the particles are made, wherein the coating
layer is free from any therapeutic substances.
32. A medical device, comprising an implantable substrate and a coating
layer, wherein the coating layer is free from any therapeutic substances but
includes particles of a polymeric material having a therapeutic substance
added thereto, wherein the therapeutic substance is completely encased
within the polymer particles.
Claims 25 and 32 under stand rejected under 35 U.S.C. § 112, second
paragraph, as indefinite.
Claims 25 and 32 under stand rejected under 35 U.S.C. § 112, first
paragraph, as lacking enablement.
Claims 32 and 35-37 stand rejected under 35 U.S.C. § 103(a) as
obvious over Ding
1
and Lentz.
2

Claims 25, 28-31, and 34 stand rejected under 35 U.S.C. § 103(a) as
obvious over Ding, Lentz, and Hunter.
3

We reverse.

1
Ding et al., US 6,099,562, August 8, 2000.
2
Lentz et al, US 2002/0133183 A1, September 19, 2002.
3
Hunter et al., US 5,886,026, March 23, 1999.
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INDEFNITENESS
According to the Examiner, claims 25 and 32 are “confusing and
unclear as to how the coating layer can „be free from any therapeutic
substances‟ when the claim[s] explicitly recite[] „polymeric particles
containing a therapeutic substance‟” (Ans. 10-11).
We do not agree that one of ordinary skill in the art would have any
difficulty understanding the claims, given their plain language, especially
when read in light of the Specification (see, e.g., Spec. 12: 29-31; 14: 28-30;
Fig. 2; Examples 1-8). The polymeric particles and the coating layer are
discrete entities. We agree with Appellants that
[I]t is abundantly clear that “free from any therapeutic
substances” refers to the coating itself (reference number 18 of
Figure 2), which is formed from a solution without any
dissolved therapeutic substances. In contrast, the microparticles
-- containing or encasing the therapeutic substances -- are
suspended in this solution, but do not dissolve in the solution.
Thus, the therapeutic substances are held on the stent by the
layer 18, but are not part of the layer 18 . . .
(App. Br. 12-13).
The rejection of claims 25 and 32 as indefinite is reversed.
ENABLEMENT
According to the Examiner, claims 25 and 32 also lack enablement
because Appellants “ha[ve] not shown how to make and obtain a drug-free
coating, particularly in view of the fact that the coating layer comprises
„polymeric particles containing a therapeutic substance‟” (Ans. 10).
We will reverse this rejection as well. As discussed above, the
polymeric particles and the coating layer are clearly discrete entities, and the
Specification provides multiple examples which explicitly teach how to form
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drug-containing polymeric particles, and how to suspend them in a solution
of a drug-free polymer, and then layer the suspension onto a stent (see, e.g.,
Spec., Example 8).
The rejection of claims 25 and 32 as lacking enablement is reversed.
OBVIOUSNESS
There are two obviousness rejections of the claims, premised in whole
or in part on the Examiner‟s proposed combination of Ding and Lentz, and
we will reverse both rejections for the reasons set forth by Appellants on
pages 13-21 of their Appeal Brief and pages 7-17 of their Reply Brief.
In a nutshell, Appellants contend that both Ding and Lentz are
directed to implantable devices coated with a homogeneous polymeric layer,
or series of homogeneous polymeric layers, containing finely divided or
dissolved drugs, rather than a polymeric layer containing discrete polymeric
particles, which in turn contain a therapeutic substance.
In the Answer, the Examiner newly admits that “Ding does not teach a
therapeutic substance encased within polymeric particles” (Ans. 7), but
nevertheless fails to establish that Lentz cures this deficiency or otherwise
provides a reason to embed discrete drug-containing polymeric particles in a
polymeric coating layer.
Quite simply, what is lacking from the references relied on by the
Examiner is the fundamental concept of embedding discrete drug-containing
polymeric particles in a polymeric coating layer, and the Examiner has not
persuasively explained how Ding and Lentz, separately or in combination,
would have led one of ordinary skill in the art to modify their coated
implantable devices in the manner required by the claims.

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SUMMARY
The rejections of claims 25 and 32 under 35 U.S.C. § 112, first and
second paragraphs, for lack of enablement and indefiniteness are reversed.
The rejection of claims 32 and 35-37 under 35 U.S.C. § 103(a) as
obvious over Ding and Lentz is reversed.
The rejection of claims 25, 28-31, and 34 under 35 U.S.C. § 103(a) as
obvious over Ding, Lentz, and Hunter is reversed.

REVERSED

cdc