Ex Parte Freeman et al

Patent Trial and Appeal Board

Dec 7, 2018

12668349 (P.T.A.B. Dec. 7, 2018)

UNITED STA TES p A TENT AND TRADEMARK OFFICE
APPLICATION NO. FILING DATE
12/668,349 04/07/2010
26138 7590 12/07/2018
Joseph R. Baker, APC
Gavrilovich, Dodd & Lindsey LLP
4370 La Jolla Village Drive, Suite 303
San Diego, CA 92122
FIRST NAMED INVENTOR
William R. Freeman
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
ATTORNEY DOCKET NO. CONFIRMATION NO.
00015-031US1 5535
EXAMINER
THAKOR, DEV ANG K
ART UNIT PAPER NUMBER
1619
MAIL DATE DELIVERY MODE
12/07/2018 PAPER
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.
PTOL-90A (Rev. 04/07)
UNITED STATES PATENT AND TRADEMARK OFFICE
BEFORE THE PATENT TRIAL AND APPEAL BOARD
Ex parte WILLIAM R. FREEMAN,
MICHAEL J. SAILOR, and LIGNYUN CHENG
Appeal2017-009648
Application 12/668,349 1
Technology Center 1600
Before DONALD E. ADAMS, RICHARD M. LEBOVITZ, and
TIMOTHY G. MAJORS, Administrative Patent Judges.
ADAMS, Administrative Patent Judge.
DECISION ON APPEAL
This Appeal under 35 U.S.C. § 134(a) involves claims 1-8, 37, 49,
and 62-64 (Final Act. 2 2; App. Br. 3 2). 4 Examiner entered rejections under
35 U.S.C. § 103(a). 5 We have jurisdiction under 35 U.S.C. § 6(b ).
We AFFIRM.
1 Appellants identify "The Regents of the University of California" and
"Spinnaker Biosciences, Inc." as the real parties in interest (App. Br. 2).
2 Examiner's November 4, 2015 Office Action.
3 Appellants' December 5, 2016 Appeal Brief.
4 Pending claims 11-20, 23, 24, 50, 52, and 53 stand withdrawn (Final Act.
2; App. Br. 2).
5 Application 11/665,557 was abandoned January 18, 2018. Therefore, the
provisional obviousness-type double patenting rejection on this record is
moot ( cf Final Act. 21-23).
Appeal2017-009648
Application 12/668,349
STATEMENT OF THE CASE
Appellants' disclosure "relates to delivery systems and, more
particularly, to a device that can deliver preprogrammed quantities of a
composition over time without the need for external power or electronics"
(Spec. ,r 3). Claims 1 is representative and reproduced below:
1. A composition comprising:
a silicon-containing material having been heated in an
oxidizing environment at a temperature above 600 QC and
comprising a plurality of pores; and
a drug or biologically active material within the pores.
(App. Br. 17.)
Grounds of rejection before this Panel for review:
Claims 1-8, 37, and 62---64 stand rejected under 35 U.S.C. § I03(a) as
unpatentable over the combination ofFreeman6 and Pap. 7
Claim 49 stands rejected under 35 U.S.C. § I03(a) as unpatentable
over the combination of Freeman, Pap, and De Vries. 8
ISSUE
Does the preponderance of evidence relied upon by Examiner support
a conclusion of obviousness?
6 Freeman et al., WO 2006/050221 A2, published May 11, 2006.
7 A. E. Pap et al., Thermal oxidation of porous silicon: Study on structure,
86 Applied Physics Letters 041501-1---041501-3 (2005).
8 De Vries, US 2003/0180294 Al, published Sept. 25, 2003.
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FACTUAL FINDINGS (FF)
FF 1. Freeman discloses:
A minimally invasive controlled drug delivery system for
delivering a particular drug or drugs to a particular location of
the eye, the system including a porous film template having
pores configured and dimensioned to at least partially receive at
least one drug therein, and wherein the template is dimensioned
to be delivered into or onto the eye.
(Freeman, Abstract.)
FF 2. Freeman's drug delivery system comprises "a silicon-containing
material that comprises a plurality of pores and a drug within the pores"
(Final Act. 6 ( citing Freeman 11: 22-34); see also Freeman 2: 23-26).
FF 3. Freeman discloses that "proteins, DNA, and various small molecules
can be attached" to its "porous Si system" (Freeman 9: 27-28; see Final Act.
8).
FF 4. Freeman discloses that "porous silicon particles can be oxidized to
increase stability and injected into animal eyes without toxicity to the
intraocular tissues since silica is a mineral needed by the body for building
bones and connective tissue" (Freeman 7: 9-12; see Final Act. 6 ("oxidation
of the silicon-containing material increases its stability and thus increases
[its] residence time")).
FF 5. Freeman discloses that "porous Si particles oxidized and annealed at
300 QC for 2 hours in air show that the material is stable in aqueous pH 11
buff er for several days, and recent results indicate that this approach can
dramatically increase the residence time of the particles in the rabbit eye"
(Freeman 14: 14--17; see Final Act. 6 ("Freeman performs oxidation through
thermal oxidation ... at 300 QC")).
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FF 6. Examiner finds that Freeman fails to disclose heating a silicon-
containing material in an oxidizing environment at a temperature above 600
QC as is required by Appellants' claimed invention (Final Act. 6).
FF 7. Pap investigated "[t]he structural changes of porous silicon (PS)
samples during oxidation" (Pap, Abstract).
FF 8. Pap discloses the oxidation of "[p ]orous silicon layers with 70%
porosity and 30 µm thickness" "in air at various temperatures, from 200 up
to 800 QC, for durations of 1 and 10 [hours]" (Pap 041501-1; see Final Act.
6).
FF 9. Pap discloses that "[ a ]t a higher oxidation temperature, Si is
increasingly transformed to Si 02, with consequential loss of crystalline
structure, resulting in a partly amorphous form" (Pap, FIG 2, Legend; see
Final Act. 6 (Examiner finds that Pap discloses "that the extent of oxidation
increases as the oxidation temperature increases"); see also Final Act. 6
(Examiner finds that Pap "show[ s] high oxidation at 600 QC ... and also
utilize[s] an even higher oxidation temperature of 800 QC")).
FF 10. Examiner finds that the combination of Freeman and Pap fails to
disclose "bevacizumab (i.e., avastin)" and relies on De Vries to make up for
this deficiency (Final Act. 8).
ANALYSIS
The rejection over the combination of Freeman and Pap:
Appellants' claim 1 is reproduced above.
Based on the combination of Freeman and Pap, Examiner concludes
that, at the time Appellants' invention was made, it would have been prima
facie obvious "to use a higher oxidation temperature, i.e., 600 QC or 800 QC
[than disclosed in Freeman], to increase the extent of oxidation and[,
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thereby,] increase the stability of the silicon material of Freeman" (Final
Act. 6). In this regard, Examiner reasons:
Given that Freeman teaches that the oxidation is the structural
attribute responsible for the increased stability, and that Pap
teaches the oxidation is not complete when using conditions
similar to those of Freeman and can be further improved, one of
ordinary skill would have reasonably expected that the stability
of the particles of Freeman could be improved by increasing the
extent of oxidation by increasing the temperature of oxidation,
and would have been motivated to do so given that Freeman
teaches that stability is advantageous.
(Ans. 9 12-13; see, e.g., FF 4--5.)
Appellants contend that Freeman does not "teach or suggest that [its]
disclosed oxidized particles were anything less than completely oxidized, or
that the extent of oxidation should be varied in order to improve the stability
of the particles," thus, "there would have been no reason, at the time of the
instant invention, for one of ordinary skill in the art to look to Pap to
increase the extent of oxidation, whether by increasing the temperature or by
any other means" (App. Br. 10 (emphasis omitted); see Reply Br. 10 3-5).
We are not persuaded.
Freeman discloses that "porous silicon particles can be oxidized to
increase stability and injected into animal eyes without toxicity to the
intraocular tissues since silica is a mineral needed by the body for building
bones and connective tissue" (FF 4). Pap establishes that by using oxidation
temperatures above those disclosed by Freeman, the oxidation state of
porous silicon particles can be increased (FF 7-9). Thus, the combination of
Freeman and Pap suggests using oxidation temperatures above those
9 Examiner's May 3, 2017 Answer.
10 Appellants' July 3, 2017 Reply Brief.
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disclosed by Freeman, such as 600 QC as disclosed by Pap, with the
expectation that more fully oxidized porous silicon particles will be obtained
that exhibit increased stability (see FF 4--5; Final Act. 6; cf Reply Br. 5
("one of ordinary skill in the art [ would not] have expected that the
conditions used by Pap to oxidize porous silicon layers would directly
translate to the oxidation of Freeman's much smaller particles with a
reasonable expectation of success")). Therefore, we are not persuaded by
Appellants' contention that "nowhere does Freeman teach or suggest that the
oxidized particles, formed either by thermal oxidation at low temperatures or
by treatment with molecular oxidants, were not sufficiently oxidized by
those treatments" or "that the stability of the particles depends on the extent
of oxidation of the particles" (App. Br. 8-9 (emphasis omitted); see also id.
at 10).
For the foregoing reasons we are not persuaded by Appellants'
contention that Examiner failed to establish "a motivation to combine
Freeman and Pap, or a reasonable expectation of success in achieving
[Appellants' claimed] ... invention," "failed to establish aprimafacie case
of obviousness," and relied upon improper hindsight (App. Br. 10 ( emphasis
omitted); see Reply Br. 3-5; cf Ans. 12-13). To the contrary, a
preponderance of the evidence of record establishes that oxidation of porous
silicon results in increased stability and reduced toxicity allowing for
increased residence times in the eye (FF 4--5). The evidence on this record
also describes the oxidation of porous silicon at a variety of different
oxidation temperatures (see FF 7-9; see First Sailor Dec. ,r 13 ("Freeman []
uses an oxidation temperature of 300 QC" and Pap "teaches that the extent of
oxidation increases as the oxidation temperature increases and ... shows a
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high level of oxidation at 600 QC and even utilizes an oxidation temperature
of 800 QC"); see also Second Sailor Dec. ,r 9).
In this regard, we note that Pap, as relied upon by Examiner, supports
Sailor's statement that "[p]orous silicon that is heated in an oxidizing
environment at a temperature above 600 QC differs structurally and
functionally in significant ways from porous silicon that has been oxidized at
lower temperatures" (see First Sailor Dec. ,r 8; see also First Sailor Dec. ,r 9;
Second Sailor Dec. ,r 5; cf FF 7-9). Therefore, we are not persuaded by
Appellants' contentions regarding differences between porous silicon
particles and layers (see App. Br. 9-10; Reply Br. 4--5). To the contrary, we
find that the evidence relied upon by Examiner supports a conclusion that it
would have been prima facie obvious for one of ordinary skill in this art to
discover, through routine experimentation, the optimum temperature to
oxidize porous silicon to achieve the benefits described by Freeman (see FF
4--5; see Ans. 5 and 7-11). See In re Aller, 220 F.2d 454,456 (CCPA 1955)
("[W]here the general conditions of a claim are disclosed in the prior art, it is
not inventive to discover the optimum or workable ranges by routine
experimentation.").
that
For the foregoing reasons, we are not persuaded by Sailor's assertion
one of ordinary skill in the art at the time of this invention
would not have looked to Pap to increase Freeman's
temperature of oxidation of porous silicon particles. This is
because, even in view of the teaching of Freeman and Pap, that
person would not have been aware of the fundamental
differences in structure and function of porous silicon oxidized
at a high temperature and, most importantly, would not have
understood how those differences in structure and function
would affect the adsorption of drugs to the particles, the long-
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term stability of those particles in animal vitreous fluid, and the
lack of toxicity of the particles in animals.
(First Sailor Dec. ,r 14; see also Second Sailor Dec. ,r 10.) See In re Aller,
220 F .2d at 456.
We are not persuaded by Appellants' evidence of unexpected results
(see App. Br. 11-14 (citing the First Sailor Dec. and Second Sailor Dec.);
see also Reply Br. 8 (referring to "qualitative comparisons that were made in
the current specification itself between particles formed at 'higher
temperatures (>700 QC)' and those formed at 'lower temperatures'
(paragraph [0073]) and between particles produced at 800 QC and those
processed at 220 QC (paragraph [0163])" and to studies comparing
"unoxidized particles" or particles thermally oxidized at either 150 Q C or
220 QC to particles thermally oxidized at 800 QC ( alteration original)); see
also Reply Br. 8-10). Sailor discusses a comparison of "particles prepared
by the thermal oxidation of porous silicon in ambient air at 220 QC for 24
hours ('Type A' conditions) to those prepared by thermal oxidation of
porous silicon in ambient air at 800 QC for 1.5 hours ('Type B' conditions)"
(First Sailor Dec. ,r 10; see also id. ,r 12; Second Sailor Dec. ,r,r 6-7). An
oxidation temperature of 220 QC is below the oxidation temperature
disclosed by, the closest prior art, Freeman and 800 QC is not commensurate
with the full scope of Appellants' claimed invention, which requires a
temperature above 600 QC (see First Sailor Dec. ,r 10; cf FF 5; Ans. 20-21;
see App. Br. 17). See In re Baxter-Travenol Labs., 952 F.2d 388, 392 (Fed.
Cir. 1991) ("[W]hen unexpected results are used as evidence of
nonobviousness, the results must be shown to be unexpected compared with
the closest prior art."); In re Dill, 604 F.2d 1356, 1361 (CCPA 1979) ("The
evidence presented to rebut a prima facie case of obviousness must be
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commensurate in scope with the claims to which it pertains."). The same is
true of Sailor's discussion of comparison of 300 Kand 1273 Kor
"temperatures up to 1000 QC" (see First Sailor Dec. ,r 11; Second Sailor Dec.
The assertions advanced by Dr. Sailor demonstrate why a comparison
that is commensurate in scope with the claimed invention is critical.
According to Sailor, based on experimental studies, "the extent of [ ethyl
violet] adsorption [to porous silicon particles] is maximal in porous silicon
particles oxidized at 400 QC and 600 QC, but decreases in particles oxidized
at 800 QC" (First Sailor Dec. ,r 12). Thus, according to Sailor, a person of
ordinary skill in this art would not have expected a decrease in absorptive
properties until an oxidation temperature of 800 QC is used (see id.).
Appellants' claimed invention, however, encompasses oxidation
temperatures below 800 QC (see App. Br. 17).
For the foregoing reasons, we are not persuaded that the evidence of
record supports a finding of unexpected results that are commensurate in
scope with Appellants' claimed invention. Therefore, we are not persuaded
by Sailor's assertion:
While Pap discloses higher-temperature thermal oxidation of
porous silicon, it in no way predicts that particles oxidized at
the higher temperatures would have such surprisingly long
residence times in animal vitreous compared to the particles of
Freeman, or that the high-temperature oxidized particles, after
removal from the vitreous, would display such remarkably low
levels of surface degradation. Nor do Freeman or Pap predict,
either alone or in combination, that the high-temperature
oxidized particles would display such low levels of toxicity,
even over long periods of time, as we [ discussed in ,r 10
describing a comparison of "the thermal oxidation of porous
silicon in ambient air at 220 QC for 24 hours ('Type A'
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conditions) to those prepared by thermal oxidation of porous
silicon in ambient air at 800 QC for 1.5 hours ('Type B'
conditions)"] and as we have observed more recently in
ongoing experiments in our laboratories.
(First Sailor Dec. ,r 14; see also id. ,r 1 O; Second Sailor Dec. ,r 11; see also
App. Br. 11 ("high-temperature oxidized porous silicon particles of the
claimed compositions have significantly different structure and function
compared to the low-temperature oxidized particles of Freeman" ( emphasis
omitted)); see also App. Br. 11-14.)
The rejection over the combination of Freeman, Pap, and De Vries:
Appellants' claim 49 depends ultimately from and further limits the
drug of Appellants' claim 1 to "bevacizumab, ranibizumab or pegaptanib"
(App. Br. 20).
Based on the combination of Freeman, Pap, and De Vries, Examiner
concludes that, at the time Appellants' invention was made, it would have
been prima facie obvious "to use the ocular drug delivery composition of
Freeman and Pap to deliver [De Vries'] bevacizumab" (Final Act. 8).
Having found no deficiency in the combination of Freeman and Pap,
we are not persuaded by Appellants' contention that De Vries fails to
overcome the deficiencies in the combination of Freeman and Pap discussed
above (see Ans. 32; cf App. Br. 15).
CONCLUSION
The preponderance of evidence relied upon by Examiner supports a
conclusion of obviousness.
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The rejection of claim 1 under 35 U.S.C. § 103(a) as unpatentable
over the combination of Freeman and Pap is affirmed. Claims 2-8, 37, and
62---64 are not separately argued and fall with claim 1.
The rejection of claim 49 under 35 U.S.C. § 103(a) as unpatentable
over the combination of Freeman, Pap, and De Vries is affirmed.
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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