Ex Parte Song et al

Board of Patent Appeals and Interferences

Oct 7, 2010

11094498 (B.P.A.I. Oct. 7, 2010)

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.
11/094,498 03/30/2005 Xuedong Song KCX-948 (20753) 1470
22827 7590 10/07/2010
DORITY & MANNING, P.A.
POST OFFICE BOX 1449
GREENVILLE, SC 29602-1449
EXAMINER
SHIBUYA, MARK LANCE
ART UNIT PAPER NUMBER
1641
MAIL DATE DELIVERY MODE
10/07/2010 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 BOARD OF PATENT APPEALS
AND INTERFERENCES
__________

Ex parte XUEDONG SONG, CHIBUEZE OBI CHIDEBELU-EZE,
and ROSANN MARIE MATTHEWS KAYLOR
__________

Appeal 2010-003210
Application 11/094,498
Technology Center 1600
__________

Before DONALD E. ADAMS, JEFFREY N. FREDMAN, and
STEPHEN WALSH, Administrative Patent Judges.

FREDMAN, Administrative Patent Judge.

DECISION ON APPEAL1
This is an appeal under 35 U.S.C. § 134 involving claims to
diagnostic test kits. The Examiner rejected the claims as obvious. We have
jurisdiction under 35 U.S.C. § 6(b). We affirm-in-part.

1 The two-month time period for filing an appeal or commencing a
civil action, as recited in 37 C.F.R. § 1.304, or for filing a request
for rehearing, as recited in 37 C.F.R. § 41.52, begins to run from
the “MAIL DATE” (paper delivery mode) or the
“NOTIFICATION DATE” (electronic delivery mode) shown on
the PTOL-90A cover letter attached to this decision.
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Statement of the Case
The Claims
Claims 1-10, 15-18, 20, 21, 31-36, 39, 40, 42, and 43 are on
appeal. Claims 1, 4, 7, and 21 are representative of the argued
claims. The remaining claims have not been argued separately and
therefore stand or fall together. 37 C.F.R. § 41.37(c)(1)(vii).
Claims 1, 4, 7, and 21 read as follows:
1. A diagnostic test kit for detecting the
presence or quantity of a test analyte within a test
sample, the diagnostic test kit comprising:
a lateral flow assay device comprising a
porous membrane, the porous membrane defining
a detection zone and a calibration zone, wherein a
first receptive material is immobilized within the
detection zone and a second receptive material is
immobilized within the calibration zone;
a plurality of assay reagents, wherein the
assay reagents comprise a calibration analyte that
is disposed on the lateral flow device, the assay
reagents further comprising detection probes and
calibration probes disposed on the lateral flow
device prior to the application of a test sample to
the device, the detection probes being disposed
upstream from the detection zone on the lateral
flow device, the calibration probes being disposed
upstream from the calibration zone on the lateral
flow device, the detection probes being conjugated
with a first specific binding member configured to
preferentially bind to the test analyte and the
calibration probes being conjugated with a second
specific binding member configured to
preferentially bind to the calibration analyte,
further wherein the first receptive material is
configured to preferentially bind to the test analyte
to form a sandwich complex, and the second
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receptive material is configured to preferentially
bind to the calibration analyte to form a sandwich
complex; and
the detection zone being capable of
producing a detection signal and the calibration
zone being capable of producing a calibration
signal, the intensity of the detection signal, as
calibrated by the intensity of the calibration signal,
being directly proportional to the
concentration of the test analyte within the
test sample.

4. The diagnostic test kit of claim 1, wherein
the calibration analyte and the test analyte are
members of the same protein family.

7. The diagnostic test kit of claim [1 , wherein
the test analyte is a pentraxin protein], wherein the
calibration analyte is a pentraxin protein.

21. The diagnostic test kit of claim 1, wherein
one or more of the assay reagents are disposed on
the lateral flow device at a location that is
upstream from a point of application for the test
sample.
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The issues
The Examiner rejected
claims 1-6, 10, 15-18, 20, 31-35, 39, 40, 42,
and 43 under 35 U.S.C. § 103(a) as obvious over
Tung2 and Selmer3 (Ans. 4-8).
claims 7-9 and 36 under 35 U.S.C. § 103(a) as
obvious over Tung, Selmer, and Rolph4 (Ans. 8-10).
claim 21 under 35 U.S.C. § 103(a) as obvious
over Tung, Selmer, and Lu5 (Ans. 10-11).
The Examiner finds it obvious to the ordinary artisan
to configure the test device of Tung et al. to form sandwich
complexes in the two discrete areas or sites as taught by
Selmer et al. because Selmer et al. teach the benefit of
creating sandwich complexes in both discrete areas by
binding to the test analyte and the calibration (control)
analyte, respectively, along with the labeled reagents, in
order to produce detectable signals in the two discrete areas
of the solid support

(id. at 6-7).
Appellants contend that “the system of Tung, et al. is based entirely
on the principle of competitive assay binding. In fact, Tung, et al.
distinguishes and teaches away from other assay systems, such as sandwich

2 Tung et al., US 6,627,459 B1, issued Sep. 30, 2003.
3 Selmer et al., US 5,387,503, issued Feb. 7, 1995.
4 Rolph et al., Production of the Long Pentraxin PTX3 in Advanced
Atherosclerotic Plaques, 22 ARTERIOSCLEROSIS THROMBOSIS AND
VASCULAR BIOLOGY 1-10 (2002).
5 Lu, US 2004/0235189 A1, published Nov. 25, 2004.
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assays” (App. Br. 9). Appellants contend that if “one were to modify Tung,
et al. as suggested in the Office Action, the positive control would instead be
indicated by the presence of color because it would rely upon sandwich
binding mechanisms. This is completely contrary to the purpose of Tung, et
al.” (Id. at 9-10.)
Appellants contend that “Tung, et al. does not involve pre-mixing and
is also a single-step calibration assay” (id. at 11). Appellants contend that a
“single-step calibration analyte assay would not exhibit a calibration curve
in which a calculable correspondence exists with a calibration curve
produced by a two-step analyte assay produced under the same reaction
conditions - a correspondence which is required for the assay of Selmer, et
al.” (Id. at 12.)
The issue with respect to this rejection is: Does the evidence of record
support the Examiner’s conclusion that the claims would have been obvious
over the prior art?
Findings of Fact
1. The figure of Tung is reproduced below:

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“The FIGURE is a schematic view of a test strip incorporating a control in
which absence of color indicates a positive result” (Tung, col. 4, ll. 13-15).
2. Tung teaches “a rapid immunoassay for a biological analyte in a
sample where the sample . . . migrates through a test strip” (Tung, col. 3, ll.
37-40).
3. Tung teaches that:
The sample is contacted with a sample pad, located
upstream of a separate conjugate pad, or with a conjugate
pad and a membrane containing a test site. The conjugate
pad contains an antibody specific to each biological analyte
and an antibody to the control analyte, each individually
labeled. The test result is read at a test site in the membrane
where a positive result for the biological analyte is an
absence of color formation at the test site, and the control
result is read at a control site in the membrane where a
positive results for the control analyte is an absence of color
formation at the control site. In one embodiment, the
immunoassay is a competitive immunoassay.

(Tung, col. 3, ll. 40-51.)
4. Tung teaches that the “membrane 20 contains a positive control
site 40, one or more test sites 45 and optionally a negative control site 50.
The positive control site 40 and optional negative control site 50 may be
either upstream or downstream relative to the test site 45” (Tung, col. 4, ll.
50-54).
5. Tung teaches that “the positive control may be a immunogenic
protein” (Tung, col. 5, ll. 33-34).
6. Tung teaches that cotinine may be used as a positive control
and that cotinine “is a surrogate of these analytes, that is, cotinine is closely
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related to the analytes in terms of molecular weight and solubility, and is
present at microgram concentrations” (Tung, col. 6, ll. 48-51).
7. Selmer teaches
a test kit for determining the amount of a test analyte in a
sample, comprising, in separate containers, (a) a
predetermined amount of a calibrator analyte which is
foreign to the sample in question, (b) a solid support to
which is bound, in a first discrete area, a reagent capable of
selectively binding the test analyte and, in a second discrete
area, a reagent capable of selectively binding the calibrator
analyte, (c) a labelled reagent capable of selectively binding
the test analyte, and (d) a similarly labelled reagent capable
of selectively binding the calibrator analyte, the labelled
reagents (c) and (d) being optionally provided as a mixture
thereof in a single container.

(Selmer, col. 2, ll. 28-43.)
8. Selmer teaches that the “calibrator analyte should be one which
is not found naturally in the sample in question, and the calibrator analyte
assay should exhibit a calibration curve which is comparable to the
calibration curve for the test analyte assay produced under the same reaction
conditions” (Selmer, col. 4, ll. 19-24).
9. Selmer teaches that the calibrator “permits correction for test
volume which is a critical factor for obtaining accurate determination
results” (Selmer 3, ll. 43-45).
10. Rolph teaches that “[l]ike CRP, PTX3 is able to bind the C1q
complement component, and it has been proposed that PTX3 may play the
same function in the periphery as CRP does in the circulation” (Rolph 2).
11. Lu teaches “providing an improved solid phase assay for
determining [a] certain analyte, and more particularly a broader assay
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spectrum by changing what is known in the art[.] The aforementioned solid
chromatographic immunoassay assay reaction order is reversed” (Lu 1 ¶
0004).
12. Lu teaches that the “present invention overcomes the aforesaid
shortcomings by changing and using the said test strip in a novel way. The
sample region is placed in front of the ligand B/tracer region and just
behind/at the ‘T’ line” (Lu 1 ¶ 0006).
Principles of Law
“The combination of familiar elements according to known methods
is likely to be obvious when it does no more than yield predictable results.”
KSR Int’l Co. v. Teleflex Inc., 550 U.S. 398, 416 (2007). “If a person of
ordinary skill can implement a predictable variation, § 103 likely bars its
patentability.” Id. at 417. Moreover, an “[e]xpress suggestion to substitute
one equivalent for another need not be present to render such substitution
obvious.” In re Fout, 675 F.2d 297, 301 (CCPA 1982). As noted by the
Court in KSR, “[a] person of ordinary skill is also a person of ordinary
creativity, not an automaton.” 550 U.S. at 421.
A reference may be said to teach away when a person of
ordinary skill, upon reading the reference, would be
discouraged from following the path set out in the reference,
or would be led in a direction divergent from the path that
was taken by the applicant. The degree of teaching away
will of course depend on the particular facts; in general, a
reference will teach away if it suggests that the line of
development flowing from the reference’s disclosure is
unlikely to be productive of the result sought by the
applicant.
In re Gurley, 27 F.3d 551, 553 (Fed. Cir. 1994).
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Analysis
Claim 1
Tung teaches a competitive lateral flow assay device comprising a
porous membrane with a detection zone, a calibration zone, where specific
antibodies are located a particular locations within these zones (FF 1-4).
Selmer teaches a standard, non competitive immunoassay (FF 7) and teaches
incorporation of a calibrator whose signal is proportional to the value of the
test analyte signal (FF 8).
Applying the KSR standard of obviousness to the findings of fact, we
conclude that the person of ordinary creativity would have predictably
modified the assay of Tung to use a standard immunoassay and a
proportional calibrator as taught by Selmer since Selmer teaches that the
calibrator “permits correction for test volume which is a critical factor for
obtaining accurate determination results” (Selmer 3, ll. 43-45; FF 9). Such a
combination is merely a “predictable use of prior art elements according to
their established functions.” KSR, 550 U.S. at 417.
Appellants contend that “the system of Tung, et al. is based entirely
on the principle of competitive assay binding. In fact, Tung, et al.
distinguishes and teaches away from other assay systems, such as sandwich
assays” (App. Br. 9). Appellants contend that if “one were to modify Tung,
et al. as suggested in the Office Action, the positive control would instead be
indicated by the presence of color because it would rely upon sandwich
binding mechanisms. This is completely contrary to the purpose of Tung, et
al.” (Id. at 9-10).
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We are not persuaded. That Tung prefers an alternative, but
equivalent, immunoassay detection mode does not teach away from the
standard immunoassay taught by Selmer. Appellants do not identify, and we
do not find, any teaching in Tung which teaches that the standard
immunoassay method of Selmer would not function. Instead, Tung teaches
the desirability of a built in positive control and the need for such controls in
competitive assays (see Tung, col. 2, ll. 37-59). See In re Fulton, 391 F.3d
1195, 1201 (Fed. Cir. 2004) (“The prior art's mere disclosure of more than
one alternative does not constitute a teaching away from any … alternatives
because such disclosure does not criticize, discredit, or otherwise discourage
the solution claimed .…”)
Appellants contend that “Tung, et al. does not involve pre-mixing and
is also a single-step calibration assay” (App. Br. 11). Appellants contend
that a “single-step calibration analyte assay would not exhibit a calibration
curve in which a calculable correspondence exists with a calibration curve
produced by a two-step analyte assay produced under the same reaction
conditions - a correspondence which is required for the assay of Selmer, et
al.” (Id. at 12.)
We are not persuaded. Claim 1 is drawn to a test kit comprising
detection and calibration zones capable of producing signals, but does not
require specific method steps such as pre-mixing or particular modes of
calibration. Selmer teaches how to obtain a calibration that is proportional
to the test sample, the capability of which is the only requirement found in
Claim 1 (FF 8), and Selmer’s zones provide the capabilities required by
claim 1. The other limitations are not found in the claim and “[L]imitations
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are not to be read into the claims from the specification.” In re Van Geuns,
988 F.2d 1181, 1184 (Fed. Cir. 1993) (citing In re Zletz, 893 F.2d 319, 321
(Fed. Cir. 1989)).
Claim 4
The Examiner finds that Tung teaches “that the control analyte and
test analyte, which can comprise proteins, can be members of the same
family, i.e. closely related” (Ans. 7).
Appellants contend that the positive control analyte cited by the
Examiner is “cotinine” and that “[c]otinine is not, however, a protein. Thus,
it certainly cannot be of the ‘same protein family’ as the test analyte as
required by claims 4 and 34” (App. Br. 14).
We conclude that Appellants have the better position. While Tung
teaches the use of proteins as controls (see Tung, col. 5, ll. 33-34), Tung
provides no teaching or reason to use proteins of the “same protein family”
as required by claims 4 and 34.
Claim 7
The Examiner finds that it would have been obvious to use pentraxin
as a calibration protein “because pentraxin 3 shares homology with CRP at
the C-terminal end but has no homology at the N-terminal end, and it has
been proposed that pentraxin 3 may play the same function in the periphery
as CRP does in the circulation” (Ans. 9-10).
Appellants contend that “there is no teaching whatsoever in any of the
references that would have led one of ordinary skill in the art to use such
pentraxin proteins as a calibration analyte” (App. Br. 14).
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We conclude that Appellants have the better position. Tung
consistently teaches that a “control analyte is one which should not cross
react with the biological analyte” (Tung, col. 4, ll. 33-34). However, the
Examiner acknowledges that pentraxin 3 shares homology with CRP, the
argued biological sample, and would therefore be expected to cross react
with CRP when antibodies which bind the C-terminal end are used (see Ans.
9-10). Further, there is no evidence in the prior art that pentraxin 3 is
necessarily segregated in vivo from CRP (see Rolph 2). We also agree with
Appellants that the Examiner has not provided a reason for either the
selection of a related protein or pentraxin 3 as a calibration control.
Claim 21
The Examiner finds it obvious “to include with the test kit of Tung et
al. and Selmer et al. the reversed chromatographic immunoassay method of
Lu wherein the sample is added between the conjugate and detection zones,
because Lu teaches the benefit of this immunoassay set-up in order to
overcome the shortcomings of the previous chromatographic
immunoassays” (Ans. 11).
Appellants contend that “Selmer, et al. expressly requires ‘pre-
mixing’ of the calibration analyte and test sample and then a ‘two-step’
application process to the solid support. This is completely contrary to a
system in which one or more of the reagents are disposed on the lateral flow
device upstream from the point of application of the test sample” (App. Br.
15).
We conclude that the Examiner has the better position. Lu provides
specific reasons for reversing the flow (FF 11-12). We are not persuaded by
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Appellants’ argument that Selmer is contrary to the system of Lu, but Selmer
rather represents a prior art system which Lu teaches is improved by
reversing the flow.
Conclusion of Law
The evidence of record support the Examiner’s conclusion that claims
1 and 21 would have been obvious over the prior art. The evidence of
record does not support the Examiner’s conclusion that claims 4 and 7
would have been obvious over the prior art.
SUMMARY
In summary, we affirm the rejection of claim 1 under 35 U.S.C. §
103(a) as obvious over Tung and Selmer. Pursuant to 37 C.F.R. §
41.37(c)(1)(vii)(2006), we also affirm the rejection of claims 2, 3, 5, 6, 15-
18, 20, 31-33, 35, 39, 40, 42, and 43 as these claims were not argued
separately.
We reverse the rejection of claims 4 and 34 under 35 U.S.C. § 103(a)
as obvious over Tung and Selmer.
We reverse the rejection of claims 7-9 and 36 under 35 U.S.C. §
103(a) as obvious over Tung, Selmer, and Rolph.
We affirm the rejection of claim 21 under 35 U.S.C. § 103(a) as
obvious over Tung, Selmer, and Lu.

No time period for taking any subsequent action in connection with
this appeal may be extended under 37 C.F.R. § 1.136(a)(1)(iv)(2006).

AFFIRMED-IN-PART
Appeal 2010-003210
Application 11/094,498

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cdc

DORITY & MANNING, P.A.
POST OFFICE BOX 1449
GREENVILLE, SC 29602-1449